Introduction to Psychology-1.12.pdf - PDFCOFFEE.COM (2023)


Introduction to the Psychology Collection Edited by: Eric Haas Content authors: OpenStax and CNX Psychology Based on: Psychology . Online: This selection and arrangement of the Content as a collection is the property of Eric Haas. Creative Commons Attribution License 4.0 Collection structure revised: 2015/05/19 PDF generated: 2020/12/01 19:48:39 For copyright and attribution information modules included in this collection, see the "Assignments" section at the end of the collection.


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Contents Preface . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 1: Introduction to Psychology. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 1.1 What is psychology? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 1.2 History of Psychology . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 1.3 Contemporary Psychology. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 1.4 Careers in Psychology. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 2: Psychological Research. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 2.1 Why is research important? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 2.2 Research Approaches . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 2.3 Analyzing Findings . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 2.4 Ethics . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 3: Biopsychology. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 3.1 Human Genetics . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 3.2 Cells of the Nervous System. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 3.3 Parts of the nervous system. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 3.4 Brain and Spinal Cord . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 3.5 The endocrine system. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 4: Sensation and Perception. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 4.1 Sensation versus Perception. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 4.2 Waves and Wavelengths . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 4.3 See . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 4.4 Hearing . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 4.5 The other senses . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 4.6 Gestalt principles of perception. 🇧🇷 🇧🇷 🇧🇷 Chapter 5: States of Consciousness . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 5.1 What is conscience? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 5.2 Sleep and why we sleep. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 5.3 Stages of sleep . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 5.4 Sleep problems and disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 5.5 Substance Use and Abuse . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 5.6 Other States of Consciousness. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 6: Learning . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 6.1 What is learning? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 6.2 Classical Conditioning . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 6.3 Operant conditioning . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 6.4 Observational Learning (Modelling) . 🇧🇷 🇧🇷 Chapter 7: Memory . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 7.1 How memory works . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 7.2 Parts of the brain involved in memory 7.3 Problems with memory . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 7.4 Ways to improve memory . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 8: Thought and Intelligence. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 8.1 What is cognition? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 8.2 Language . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 8.3 Troubleshooting . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 8.4 What are intelligence and creativity? 🇧🇷 8.5 Intelligence Measures . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 8.6 The Source of Intelligence . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 9: Emotion and Motivation. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 9.1 Motivation . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷

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9.2 Hunger and Eating . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 9.3 Sexual Behavior . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 9.4 Emotions . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 10: Lifespan Evolution . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 10.1 What is lifelong evolution? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 10.2 Theories of Life . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 10.3 Stages of Development . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 10.4 Death and Dying . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 11: Personality. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.1 What is personality? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.2 Freud and the psychodynamic perspective. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.3 Neo-Freudians: Adler, Erikson, Jung and Horney. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.4 Approaches to learning . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.5 Humanistic Approaches . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.6 Biological Approaches . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.7 Property Theories. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.8 Cultural understanding of personality. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 11.9 Personality Assessment . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 12: Mental Disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.1 What are mental disorders? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.2 Diagnosis and classification of mental disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.3 Perspectives on mental disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.4 Anxiety disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.5 Obsessive-Compulsive and Related Disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.6 Post Traumatic Stress Disorder . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.7 Mood disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.8 Schizophrenia. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.9 Dissociative Disorders . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.10 Personality Disorders. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 12.11 Childhood Disorders . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 13: Stress, lifestyle and health. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 13.1 What is stress? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 13.2 Stressors . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 13.3 Stress and Illness . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 13.4 Stress regulation . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 13.5 The Pursuit of Happiness . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 14: Therapy and Treatment. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 14.1 Mental Health Treatment: Past and Present . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 14.2 Types of Treatment . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 14.3 Treatment modalities. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 14.4 Substance and addictive disorders: A special case 14.5 Sociocultural model and application of therapy . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Chapter 15: Social Psychology. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 15.1 What is social psychology? 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 15.2 Self-introduction . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 15.3 Attitudes and Beliefs . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 15.4 Compliance, Compliance and Compliance . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 15.5 Prejudice and Discrimination . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 15.6 Assault. 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 15.7 Prosocial behavior . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 Index . 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷 🇧🇷

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Preface Welcome to Psychology, an OpenStax resource. This book was written to increase students' access to quality study materials and to maintain the highest standards of academic rigor at little or no cost.

ABOUT OPENSTAX OpenStax is a not-for-profit organization headquartered at Rice University and our mission is to improve student access to education. Our first publicly licensed college textbook was released in 2012, and since then our library has grown to over 25 AP® college and course books used by hundreds of thousands of students. Our adaptive learning technology, designed to improve learning outcomes through personalized educational pathways, is being tested in college courses across the country. Through our partnerships with philanthropic foundations and our alliance with other educational resource organizations, OpenStax breaks down the most common barriers to learning and empowers students and teachers to succeed.

ABOUT OPENSTAX FEATURES Customization Psychology is licensed under a Creative Commons Attribution 4.0 International (CC BY) license, which means you can distribute, remix, and build on the content as long as you credit OpenStax and its content providers. As our books are openly licensed, you can use the entire book or select the sections most relevant to your course needs. Feel free to rearrange the content by assigning your students specific chapters and sections in your curriculum in any order you prefer. You can even provide a direct link to sections in your book's web view in your syllabus. Instructors also have the option of creating a customized version of their OpenStax book. The customized version can be made available to students in cost-effective hard copy or in digital format through the campus bookstore. Visit his book page on for more information.

Errata All OpenStax textbooks undergo a rigorous review process. However, as with any professional book, mistakes sometimes occur. As our books are web-based, we may update them regularly when deemed pedagogically necessary. If you have a suggested correction, please submit it using the link on your book page at Subject matter experts review all proposed errata. OpenStax strives to be transparent with all updates, so you can also find a list of past errata changes on its book page at

Format This book is freely available in web preview or in PDF format via, as well as affordable print and iBooks editions.

ABOUT PSYCHOLOGY Psychology is tailored to the scope and structure of the one-semester introductory psychology course. The book provides a comprehensive treatment of the basics, drawing on classic studies and current and emerging research. The text also includes DSM-5 coverage of mental disorder investigations. Psychology engages with discussions that reflect the diversity within the discipline, as well as the diversity of cultures and communities around the world.



Coverage and Scope This book aims to make psychology an interesting and accessible discipline for student research and examples that represent and embody the diverse sociocultural backgrounds of the many students who take this course. The result is a book that covers the range of psychological topics with breadth and depth that promote student engagement. The organization and pedagogical resources were developed and validated with feedback from psychologist educators dedicated to the project. Chapter 1: Introduction to Psychology Chapter 2: Psychological Research Chapter 3: Biopsychology Chapter 4: States of Consciousness Chapter 5: Sensing and Perception Chapter 6: Learning Chapter 7: Thinking and Intelligence Chapter 8: Memory Chapter 9: Lifelong Development Chapter 10: Motivation and Emotion Chapter 11: Personality Chapter 12: Social Psychology Chapter 13: Work and Organizational Psychology Chapter 14: Stress, Lifestyle, and Health Chapter 15: Mental Illness Chapter 16: Therapy and Treatment

Pedagogical Foundations Throughout Psychology, you'll find resources that engage students in psychological inquiry by taking selected topics one step further. Everyday Connection features connect psychological themes to everyday issues and behaviors that students encounter in their lives and in the world. Topics include the validity of university entrance exam results, advertising and associative learning, and cognitive mapping. What do you think? Resources provide research-based information and solicit student input on controversial topics. Topics include brain death and life support, Hooters and BFOQ laws, and criminals with intellectual disabilities and capital punishment. Dig Deeper resources discuss a specific aspect of a topic in more detail, allowing students to dig deeper into the concept. Examples include a discussion of the distinction between evolutionary psychology and behavioral genetics, an analysis of the rising prevalence rate of ADHD, and a presentation of research on strategies for dealing with prejudice and discrimination. Connect the Concepts features revisit a concept learned in another chapter and expand on it in a different context. Features include "Autism Spectrum Disorder and the Expression of Emotions," "Preadolescents, Adolescents, and Social Norms," ​​and "Conditioning and Obsessive-Compulsive Disorder."

Inspiring Arts, Interactions, and Assessments Our Arts program is designed to increase students' understanding of psychological concepts

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simple and effective charts, graphs and photos. Psychology also includes links to relevant interactive exercises and animations to help bring topics to life. Selected assessment items directly affect students' lives. Link to Learning features direct students to interactive online exercises and animations that add richer context to core content and provide an opportunity for application. Personal Application Questions engage students on a personal level with questions to stimulate thinking and encourage discussion.

ADDITIONAL RESOURCES Resources for Students and Teachers We've put together additional resources for students and teachers, including getting started guides, a solution guide for teachers, a test bench, and PowerPoint slides. Instructor resources require a verified instructor account, which you can request when logging in or creating your account at Use these resources to complement your OpenStax book.

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ABOUT THE AUTHORS Authors Senior Contributors Rose M. Spielman (Content Lead) Dr. Rose Spielman teaches psychology and has been a licensed clinical psychologist for 20 years. Her academic career includes positions at Quinnipiac University, Housatonic Community College and Goodwin College. As a licensed clinical psychologist, educator, and volunteer leader, Rose is able to connect with people from diverse backgrounds and facilitate treatment, advocacy, and education. Over her years working as a teacher, therapist, and administrator, she has helped thousands of students and clients, teaching them how to advocate for themselves and move forward in their lives to become more productive citizens and family members. Kathryn Dumper, Bainbridge State College William Jenkins, Mercer University Arlene Lacombe, Saint Joseph's University Marilyn Lovett, Livingstone College Marion Perlmutter, University of Michigan

Gutachter Daniel Bellack, Trident Technical College Jerimy Blowers, Cayuga Community College Salena Brody, Collin College Bettina Casad, University of Missouri–St. Louis Sharon Chacon, Northeast Wisconsin Technical College Barbara Chappell, Walden University James Corpening Frank Eyetsemitan, Roger Williams University Tamara Ferguson, Utah State University Kathleen Flannery, Saint Anselm College Johnathan Forbey, Ball State University


Laura Gaudet, Chadron State College William Goggin, University of Southern Mississippi Jeffery K. Gray, Charleston Southern University Heather Griffiths, Fayetteville State University Mark Holder, University of British Columbia Rita Houge, Des Moines Area Community College Colette Jacquot, Strayer University John Johanson, Winona State University Andrew Johnson, Park University Shaila Khan, Tougaloo College Carol Laman, Houston Community College Thomas Malloy, Rhode Island College Jan Mendoza, Golden West College Christopher Miller, University of Minnesota Lisa Moeller, Beckfield College Hugh Riley, Baylor University Juan Salinas, University of Texas at Austin Brittney Schrick, Southern Arkansas University Phoebe Scotland, College of the Rockies Christine Selby, Husson University Brian Sexton, Kean University Nancy Simpson, Trident Technical College Robert Stennett, University of Georgia Jennifer Stevenson, Ursinus College Eric Weiser, Curry College Valjean Whitlow, Amerikanische Öffen tliche Uni Vers

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Chapter 1 | Introduction to Psychology


Chapter 1

Introduction to Psychology

Figure 1.1 Psychology is the scientific study of the mind and behavior. (Bottom credit: modification of work by Nattachai Noogure; top left credit: modification of work by US Navy; top left center credit: modification of work by Peter Shanks; top right credit center: modification of work by "devinf"/Flickr ; "Top Right" credit: Modification of work by Alejandra Quintero Sinisterra; Credit "Bottom Left": Modification of work by Gabriel Rocha; Credit "Bottom Center Left": Modification of work by Caleb Roenigk; Credit "bottom center-right": modification of work by Staffan Scherz; photo credit "bottom right": modification of work by Czech Province Reconstruction Team)

Chapter Overview 1.1 What is psychology? 1.2 History of Psychology 1.3 Contemporary Psychology 1.4 Careers in Psychology

Introduction Clive Wearing is a talented musician who lost the ability to form new memories when he fell ill at the age of 46. Although he remembers how to play the piano perfectly, he cannot remember what he had for breakfast an hour ago (Sacks, 2007). James Wannerton lives a taste experience linked to the sound of words. The ex-girlfriend's name tastes like rhubarb (Mundasad, 2013). John Nash is a brilliant mathematician and Nobel Prize winner. However, when he was a professor at MIT, he told people that the New York Times contained coded messages from extraterrestrials intended for him. He also started to hear voices and became suspicious of the people around him. Soon after, Nash was diagnosed with schizophrenia and committed to a state mental institution (O'Connor & Robertson, 2002). Nash was the subject of the 2001 film A Beautiful Mind. Why did these people have these experiences? How does the human brain work? And what is the connection between the brain's internal processes and people's external behavior? This book will present several ways in which psychology has studied these questions.


Chapter 1 | Introduction to Psychology

1.1 What is psychology? Learning Outcomes By the end of this section you will be able to: • understand the etymology of the word 'psychology' • define psychology • understand the benefits of an education in psychology In Greek mythology, Psyche was a mortal woman whose beauty was so magnificent that it rivaled that of the goddess Aphrodite. Aphrodite was so jealous of Psyche that she sent her son Eros to make Psyche fall in love with the ugliest man in the world. However, Eros accidentally stabbed himself with the tip of his arrow and fell head over heels in love with Psyche herself. He took Psyche to her palace and showered her with gifts, but she never saw her face. When they visited Psyche, her sisters aroused Psyche's suspicions about her mysterious lover, and eventually Psyche betrayed Eros's desire to remain invisible to her (Figure 1.2). Because of this betrayal, Eros left Psyche. When Psyche asked Aphrodite to reunite her with Eros, Aphrodite gave her a series of impossible tasks to complete. Psyche managed to complete all of these attempts; Ultimately, her persistence paid off when she was reunited with Eros and eventually transformed into a goddess (Ashliman, 2001; Greek Myths and Greek Mythology, 2014).

Figure 1.2 A sculpture by Antonio Canova shows Eros and Psyche.

Psyche represents the triumph of the human soul over the misfortunes of life in search of true happiness (Bulfinch, 1855); In fact, the Greek word Psyche means soul and is often depicted as a butterfly. The word psychology was coined at a time when the concepts of soul and spirit were not so clearly separated (Green, 2001). Rootology refers to the scientific study of the mind, and psychology refers to the scientific study of the mind. Since science only studies observable phenomena and the mind is not directly observable, we extend this definition to the scientific study of the mind and behavior. The scientific study of all aspects of the world uses the scientific method to acquire knowledge. To use the scientific method, with a question about how or why something happens, a researcher proposes a tentative explanation called a hypothesis to explain the phenomenon. A hypothesis is not just any explanation; must fit within the context of a scientific theory. A scientific theory is a broad explanation or set of explanations for some aspect of the natural world that is supported by evidence over time. A theory is the best understanding we have of that part of the natural world. Armed with the hypothesis, the researcher then makes observations or, better yet, conducts an experiment to test the validity of the hypothesis. This test and its results are then published for others to review or build on the results. Every explanation in science needs to be verifiable, which means that the phenomenon must be perceivable and measurable. For example, that a bird sings because it is happy is not

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Chapter 1 | Introduction to Psychology


a testable hypothesis, since we cannot measure a bird's happiness. We need to ask another question, perhaps about the bird's brain state, as this can be measured. Science usually deals only with matter and energy, that is, with things that can be measured, and cannot reach conclusions about values ​​and morals. This is one of the reasons why our scientific understanding of the mind is so limited, since thoughts, at least as we experience them, are neither matter nor energy. The scientific method is also a form of empiricism. An empirical method of acquiring knowledge is based on observation, including experimentation, rather than one based solely on forms of logical reasoning or prior authority. Psychology was not recognized as an independent academic discipline until the end of the 19th century. Prior to that time, the workings of the mind were viewed under the auspices of philosophy. Since all behavior is biological at its roots, some branches of psychology borrow aspects of a natural science like biology. No biological organism exists in isolation, and our behavior is influenced by our interactions with others. Therefore, psychology is also a social science.

BENEFITS OF PSYCHOLOGY TRAINING Students often take their first psychology course because they are interested in helping others and want to learn more about themselves and why they act the way they do. Sometimes students take a psychology course because it meets a general educational requirement or is needed for a degree like nursing or medicine. Many of these students develop such an interest in the field that they make psychology their specialty. As a result, psychology is one of the most popular majors at US universities (Johnson & Lubin, 2011). Several well-known people were psychology students. Just a few famous names on this list are Facebook creator Mark Zuckerberg, television personality and political satirist Jon Stewart, actress Natalie Portman, and filmmaker Wes Craven (Halonen, 2011). About 6% of all bachelor's degrees awarded in the United States are in the discipline of psychology (US Department of Education, 2013). An education in psychology is valuable for several reasons. Psychology students improve critical thinking skills and are trained in the application of the scientific method. Critical thinking is the active application of a variety of skills to information in order to understand and evaluate that information. Evaluating information – judging its reliability and usefulness – is an important skill in a world full of competing “facts”, many of which are considered misleading. For example, critical thinking involves maintaining a skeptical attitude, recognizing internal biases, using logical thinking, asking appropriate questions, and making observations. Psychology students can also develop better communication skills during their undergraduate studies (American Psychological Association, 2011). Together, these factors increase students' scientific literacy and prepare them to critically evaluate the various sources of information they encounter. In addition to these broad skills, psychology students understand the complex factors that shape someone's behavior. They value the interplay of our biology, our environment and our experiences to determine who we are and how we will behave. They learn basic principles that guide our thinking and behavior and recognize the enormous diversity that exists across individual and cultural boundaries (American Psychological Association, 2011).

LINK TO LEARN Watch a short video ( that outlines some of the questions a student should consider before deciding to study psychology.


Chapter 1 | Introduction to Psychology

1.2 History of Psychology Learning Outcomes By the end of this section you will be able to: • Understand the importance of Wundt and James in the development of psychology • Appreciate Freud's influence on psychology • Understand the basic principles of Gestalt psychology • Understand what is important role behaviorism played in the history of psychology • Understand the basic tenets of humanism • Understand how the cognitive revolution shifted the focus of psychology back to the mind Psychology is a relatively young science, with experimental roots in the 19th century, by comparison , for example, to human physiology, which dates back much earlier. As noted above, anyone interested in studying issues related to the mind usually did so in a pre-19th century philosophical context. Two men working in the 19th century are generally considered to be the founders of psychology as a science and academic discipline distinct from philosophy. Their names were Wilhelm Wundt and William James. This section provides an overview of the paradigm shifts that have influenced Wundt and James psychology to date.

WUNDT AND STRUCTURALISM Wilhelm Wundt (1832-1920) was a German scientist who was the first to be called a psychologist. His famous book entitled Principles of Physiological Psychology was published in 1873. Wundt viewed psychology as the scientific study of conscious experience and believed that the aim of psychology was to identify the components of consciousness and how these components combined result in our conscious experience. Wundt used introspection (he called it "inner perception"), a process by which one examines one's own conscious experience as objectively as possible, making the human mind like any other aspect of nature that a scientist observes. Wundt's version of introspection used only very specific experimental conditions in which an external stimulus was designed to elicit a scientifically observable (repeatable) experience of the mind (Danziger, 1980). The first strict requirement was the use of "trained" or experienced observers who could immediately observe and report a reaction. The second requirement was the use of repeatable stimuli that would always evoke the same experience in the subject and allow the subject to anticipate and thus pay full attention to the internal response. These experiential requirements were introduced to eliminate “interpretation” when reporting internal experiences and to combat the argument that there is no way to know whether a person is closely observing their mind or consciousness because no other person can be seen. This attempt to understand the structure or properties of the mind was called structuralism. In 1879, Wundt set up his psychology laboratory at the University of Leipzig (Fig. 1.3). In this laboratory, Wundt and his students performed experiments on reaction times, for example. A subject, sometimes in an isolated room from the scientist, would receive a stimulus such as light, image or sound. The subject's response to the stimulus would be to press a button, and a device would record the response time. Wundt was able to measure reaction time down to one thousandth of a second (Nicolas & Ferrand, 1999).

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Chapter 1 | Introduction to Psychology


Figure 1.3 (a) Wilhelm Wundt is considered one of the founders of psychology. He created the first psychological research laboratory. (b) This photo shows him sitting and surrounded by other researchers and equipment in his laboratory in Germany.

However, despite their efforts to train individuals in the introspection process, this process remained highly subjective and there was very little agreement between individuals. As a result, structuralism fell out of favor with the death of Wundt's student Edward Titchener in 1927 (Gordon, 1995).

JAMES AND FUNCTIONALISM William James (1842-1910) was the first American psychologist to offer a different view of how psychology works (Figure 1.4). James was introduced to Darwin's theory of evolution through natural selection and accepted it as an explanation for an organism's characteristics. Key to this theory is the idea that natural selection results in organisms adapted to their environment, including their behavior. Adaptation means that a characteristic of an organism has a function for the survival and reproduction of the individual because it was selected naturally. In James' view, the purpose of psychology was to study the function of behavior in the world, and as such, his perspective was known as functionalism. Functionalism focused on how mental activities help an organism adapt to its environment. Functionalism has a second, more subtle meaning, as functionalists were more interested in the workings of the mind as a whole rather than its individual parts, which was the focus of structuralism. Like Wundt, James believed that introspection could serve as a means by which one could study mental activity, but James also relied on more objective measures, including the use of various recording devices and the study of concrete products of mental activity and anatomy and physiology (Gordon, 1995).

Figure 1.4 William James, seen here in a self-portrait, was the first American psychologist.


Chapter 1 | Introduction to Psychology

FREUD AND PSYCHOANALYTICAL THEORY Perhaps one of the most influential and well-known figures in the history of psychology was Sigmund Freud (Figure 1.5). Freud (1856-1939) was an Austrian neurologist who was fascinated by patients with "hysteria" and neurosis. Hysteria was an old diagnosis for disorders, mostly of women, with a variety of symptoms, including physical symptoms and emotional disturbances, none of which had an obvious physical cause. Freud theorized that many of his patients' problems stem from the subconscious. In Freud's view, the unconscious was a repository of feelings and impulses of which we are not aware. Access to the unconscious was therefore crucial to the successful resolution of the patient's problems. According to Freud, the unconscious could be reached through the analysis of dreams, through the study of the first words that came to people's minds and through seemingly harmless slips of the tongue. Psychoanalytic theory focuses on the role of a person's unconscious as well as early childhood experiences, and this particular perspective has dominated clinical psychology for several decades (Thorne & Henley, 2005).

Figure 1.5 (a) Sigmund Freud was an extremely influential figure in the history of psychology. (b) One of his many books, A General Introduction to Psychoanalysis, shared his ideas on psychoanalytic therapy; was published in 1922.

Freud's ideas were influential, and you'll learn more about them as you explore life development, personality, and therapy. For example, many therapists have strong beliefs in the unconscious and in the impact of early childhood experiences on the rest of a person's life. The method of psychoanalysis, in which the patient talks about his experiences and himself, was not invented by Freud, but he certainly popularized it and is still used today. However, many of Freud's other ideas are controversial. Drew Westen (1998) argues that many criticisms of Freud's ideas are misguided because they attack his earlier ideas without considering later writings. Westen also argues that critics fail to consider the success of broad ideas introduced or developed by Freud, such as the importance of childhood experiences in adult motivation, the role of unconscious versus conscious motivations in controlling our behavior, the fact that motivations can cause conflict. affect behavior, the impact of mental representations of ourselves and others on controlling our interactions, and personality development over time. For all of these ideas, West identifies support from subsequent research. More modern iterations of Freud's clinical approach have been shown to be empirically effective (Knekt et al., 2008; Shedler, 2010). Some current practices in psychotherapy involve examining unconscious aspects of the self and relationships, often through the therapist-client relationship.

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Chapter 1 | Introduction to Psychology


Freud's historical importance and contributions to clinical practice deserve to be included in the discussion of historical movements in psychology.

WERTHEIMER, KOFFKA, KÖHLER AND GESTRAL PSYCHOLOGY Max Wertheimer (1880–1943), Kurt Koffka (1886–1941) and Wolfgang Köhler (1887–1967) were three German psychologists who immigrated to the United States in the early 20th century fleeing the Nazis Germany. These men are credited with introducing many of the Gestalt principles to psychologists in the United States. The word gestalt means roughly translated "whole"; One of the main focuses of Gestalt psychology addresses the fact that, although a sensory experience can be divided into distinct parts, the relationship of these parts to each other as a whole is often what the individual responds to in perception. For example, a song may consist of individual notes played by different instruments, but the true nature of music is seen in the combinations of these notes as they form melody, rhythm, and harmony. In many ways, this particular perspective would have directly contradicted Wundt's ideas of structuralism (Thorne & Henley, 2005). Unfortunately, when these men moved to the United States, they were forced to give up most of their jobs and were unable to continue their research on a large scale. These factors, along with the rise of behaviorism (described below) in the United States, prevented the principles of Gestalt psychology from being as influential in the United States as they were in their native Germany (Thorne & Henley, 2005). Despite these problems, some Gestalt principles are still very influential today. Viewing the human individual as a whole, rather than the sum of individually measured parts, became an important foundation of humanist theory towards the end of the century. Gestalt ideas continued to influence sensation and perception research. Structuralism, Freud, and Gestalt psychologists were all concerned in one way or another with describing and understanding inner experiences. Other researchers, however, feared that inner experience might be a legitimate subject for scientific investigation, and instead chose to study exclusively behavior, the objectively observable result of mental processes.

PAVLOV, WATSON, SKINNER AND BEHAVIORISM The first work in the field of behavior was done by the Russian physiologist Ivan Pavlov (1849-1936). Pavlov studied a form of learning behavior called the conditioned reflex, in which an animal or human elicits a reflexive (unconscious) response to a stimulus and is conditioned over time to produce the response to another stimulus that the experimenter chooses as the stimulus associated with the stimulus. original . The reflex that Pavlov worked with was salivation in response to the presence of food. The salivary reflex can be triggered by a second stimulus, e.g. B. a particular sound presented several times in connection with the initial food stimulus. Once the response to the second stimulus was "learned", the food stimulus could be omitted. Pavlov's "classical conditioning" is just one form of learning behavior studied by behaviorists. John B. Watson (1878-1958) was an influential American psychologist whose most famous work was at Johns Hopkins University in the early 20th century (Figure 1.6). While Wundt and James were concerned with understanding conscious experience, Watson found the study of consciousness flawed. Believing that objective analysis of the mind was impossible, Watson preferred to focus directly on observable behavior and try to control that behavior. Watson was a leading advocate of shifting the focus of psychology from mind to behavior, and this approach to observing and controlling behavior became known as behaviorism. One of the main subjects of study by behaviorists has been learned behavior and its interaction with the innate characteristics of the organism. Behaviorism used to use animals in experiments with the assumption that what was learned in animal models could be applied to human behavior to some extent. Indeed, Tolman (1938) stated: "I believe that everything of importance in psychology (except ... such questions concerning society and words) can be essentially investigated by continuing experimental and theoretical analysis of the determinants of rat behavior in a given point at


Chapter 1 | Introduction to Psychology

a labyrinth.”

Figure 1.6 John B. Watson is known as the father of behaviorism in psychology.

Behaviorism dominated experimental psychology for several decades, and its influence is still felt today (Thorne & Henley, 2005). Behaviorism, through its objective methods and mainly experimentation, is largely responsible for establishing psychology as a scientific discipline. In addition, it is used in behavioral and cognitive-behavioral therapy. Behavior modification is commonly used in classrooms. Behaviorism also led to the study of environmental influences on human behavior. B. F. Skinner (1904-1990) was an American psychologist (Figure 1.7). Skinner, like Watson, was a behaviorist and focused on how behavior is affected by its consequences. Therefore, Skinner spoke of reinforcement and punishment as important factors in driving behavior. As part of his research, Skinner developed a chamber that allowed careful study of the principles of behavior modification by reinforcement and punishment. Known as an operant conditioning chamber (or more commonly known as a Skinner box), this device remains a crucial resource for researchers who study behavior (Thorne & Henley, 2005).

Figure 1.7 (a) B. F. Skinner is famous for his research on operant conditioning. (b) Modified versions of the operant conditioning chamber or Skinner box are still commonly used in research settings today. (Credit to: Modification of work by "Silly Rabbit"/Wikimedia Commons)

Skinner's box is a chamber that isolates the subject from the external environment and has a behavioral indicator such as a lever or button. When the animal presses the button or lever, the box can provide positive behavior reinforcement (e.g. food) or punishment (e.g. a sound) or symbolic conditioning (e.g. a light), the correlate of both is positive reinforcement or punishment. Skinner's focus on positive and negative reinforcement of learned behaviors had a lasting impact on psychology that waned somewhat as research in cognitive psychology grew. Despite this, conditioned learning is still used in human behavior modification. Skinner's two widely read and controversial popular science books on the value of operant conditioning for a happier life

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Chapter 1 | Introduction to Psychology


remain as instigating arguments for his approach (Greengrass, 2004).

MASLOW, ROGERS, AND HUMANISM In the early twentieth century, American psychology was dominated by behaviorism and psychoanalysis. However, some psychologists were uncomfortable that what they saw as limited perspectives had such a large impact on the field. They opposed Freud's pessimism and determinism (all actions directed by the unconscious). They also disliked reductionism or the simplistic nature of behaviorism. Behaviorism is also deterministic to the core, because it sees human behavior as entirely determined by a combination of genetics and environment. Some psychologists began to develop their own ideas that emphasized personal control, intentionality, and a genuine disposition for "good" as important to our self-concept and behavior. Thus humanism was born. Humanism is a perspective within psychology that emphasizes the potential for good inherent in all human beings. Two of the best-known exponents of humanistic psychology are Abraham Maslow and Carl Rogers (O'Hara, undated). Abraham Maslow (1908-1970) was an American psychologist best known for proposing a hierarchy of human needs in motivational behavior (Figure 1.8). Although this concept is discussed in more detail in a later chapter, a brief overview is provided here. Maslow stated that as long as the basic needs necessary for survival are met (e.g. food, water, shelter), higher needs (e.g. social needs) would begin to motivate behavior. According to Maslow, the highest needs are related to self-actualization, a process by which we realize our full potential. Obviously, the focus on the positive aspects of human nature characteristic of the humanist perspective is evident (Thorne & Henley, 2005). Humanistic psychologists fundamentally rejected the research approach based on reductive experimentation in the tradition of the physical and biological sciences because it missed the "whole" human being. Beginning with Maslow and Rogers, a humanistic research program was insisted upon. This program has been largely qualitative (not measurement-based), but there are a number of strands of quantitative research within humanistic psychology, including research on happiness, self-concept, meditation, and the outcomes of humanistic psychotherapy (Friedman, 2008).

Figure 1.8 shows Maslow's hierarchy of needs.

Carl Rogers (1902-1987) was also an American psychologist who, like Maslow, emphasized the potential


Chapter 1 | Introduction to Psychology

for the good that is in all people (Figure 1.9). Rogers used a therapeutic technique known as client-centered therapy to help his clients deal with the troublesome issues that caused them to seek psychotherapy. In contrast to a psychoanalytic approach, in which the therapist plays an important role in interpreting what conscious behavior reveals about the unconscious, client-centered therapy involves the patient taking a leadership role in the therapy session. Rogers believed that to maximize the effectiveness of this particular approach, a therapist must demonstrate three qualities: unconditional positive regard, genuineness, and empathy. Unconditional positive regard refers to the fact that the therapist accepts his client as he is, no matter what he says. Given these factors, Rogers believed that people were more than capable of coping and dealing with their own problems (Thorne & Henley, 2005).

Figure 1.9 Carl Rogers, featured in this portrait, developed a client-centered approach to therapy that had an impact on the clinical setting. (Image credit: “Didius”/Wikimedia Commons)

Humanism influenced psychology as a whole. Both Maslow and Rogers are household names among psychology students (you'll read more about both men later in this text), and their ideas have influenced many scholars. Furthermore, Rogers' client-centered therapeutic approach is still commonly used in psychotherapeutic contexts today (O'hara, undated).

LINK TO LEARN Watch a short video ( in which Carl Rogers describes his therapeutic approach.

THE COGNITIVE REVOLUTION Behaviorism's emphasis on objectivity and the focus on external behavior long distracted psychologists from the mind. Early work by humanistic psychologists drew attention to the individual human being as a whole and as a conscious, self-aware being. In the 1950s, new disciplinary perspectives emerged in linguistics, neuroscience, and computer science, and these areas revived interest in the mind as a focus of scientific inquiry. This particular perspective came to be known as the cognitive revolution (Miller, 2003). In 1967, Ulric Neisser published the first textbook, Cognitive Psychology, which served as the central text in cognitive psychology courses across the country (Thorne & Henley, 2005). While no one is solely responsible for starting the cognitive revolution, Noam Chomsky was highly influential in the early days of the movement (Figure 1.10). Chomsky (1928–), an American linguist, was dissatisfied with the impact behaviorism was having on psychology. he thought so

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Chapter 1 | Introduction to Psychology


psychology's focus on behavior is myopic and that the field must reintegrate mental functioning into its mission if it is to make meaningful contributions to the understanding of behavior (Miller, 2003).

Figure 1.10 Noam Chomsky was very influential in starting the cognitive revolution. In 2010, this mural was erected in his honor in Philadelphia, Pennsylvania. (Image credit: Robert Moran)

European psychology was never really influenced by behaviorism like American psychology was; and so the cognitive revolution helped restore the lines of communication between European psychologists and their American counterparts. In addition, psychologists began collaborating with scientists in other fields, such as anthropology, linguistics, computer science, and neuroscience. This interdisciplinary approach has often been referred to as cognitive science, and the influence and importance of this particular perspective resonates in modern psychology (Miller, 2003).

DIG DEEPER Feminist Psychology The science of psychology has both positive and negative implications for human well-being. The predominant influence of Western, white, male scholars in the early history of psychology meant that psychology developed with the biases inherent in these individuals, often with negative consequences for members of society who were not white or male. Women, members of ethnic minorities both in the United States and abroad, and individuals with sexual orientations other than heterosexual have had difficulty entering the field of psychology and influencing its development. They also suffered from the attitudes of white male psychologists who were not immune to the unscientific attitudes prevalent in the society in which they grew up and worked. Until the 1960s, the science of psychology was largely "womenless" psychology (Crawford & Marecek, 1989), meaning that few women were able to practice psychology, so they had little influence on what was studied. Furthermore, psychology subjects were mostly men, resulting from the underlying assumption that gender had no bearing on psychology and that women were not of sufficient interest to study. An article by Naomi Weisstein, first published in 1968 (Weisstein, 1993), sparked a feminist revolution in psychology by presenting a critique of psychology as a science. She also specifically criticized male psychologists for constructing women's psychology entirely out of their own cultural biases and without careful experimental testing to verify any of their characterizations of women. As examples, Weisstein cited statements by prominent psychologists of the 1960s, such as this quote from Bruno Bettleheim: ". . . We must begin by recognizing that as much as women want to be good scientists or engineers, they being female companions to men and mothers The impact of male cultural biases on our knowledge of the psychology of women and indeed of both sexes Crawford & Marecek (1989) identify several feminist approaches to psychology that might be called feminist psychology This includes reassessing and uncovering women's contributions to the history of psychology, examining psychological gender differences, and challenging male biases that are pervasive.


Chapter 1 | Introduction to Psychology

Practice of scientific access to knowledge.

MULTICULTURAL PSYCHOLOGY Culture has important implications for individuals and for social psychology, but the impact of culture on psychology is understudied. There is a risk that psychological theories and data drawn from white American settings will be applied to individuals and social groups from other cultures, and this is probably not the case (Betancourt & López, 1993). A weakness in the field of intercultural psychology is that, when looking for differences in psychological characteristics across cultures, it is necessary to go beyond simple descriptive statistics (Betancourt & López, 1993). In that sense, it remained a descriptive science, not one that tries to determine cause and effect. For example, a study of the characteristics of individuals seeking treatment for binge eating disorder among Hispanics, African Americans, and Caucasian Americans found significant differences between groups (Franko et al., 2012). The study concluded that the test results of one of the groups could not be extrapolated to the other groups, and yet the possible causes of the differences were not measured. This history of multicultural psychology in the United States is a long one. The role of African American psychologists in exploring cultural differences between the African American individual and social psychology is just one example. In 1920, Cecil Sumner was the first African American to earn a doctorate in psychology in the United States. Sumner established a psychology program at Howard University that led to the training of a new generation of African-American psychologists (Black, Spence, and Omari, 2004). Much of the work of early African American psychologists (and a common focus of much psychological work in the first half of the 20th century in the United States) was devoted to testing, and specifically, testing of intelligence (Black et al., 2004). 🇧🇷 This emphasis has continued, primarily because of the importance of testing in determining children's opportunities, but other areas of investigation in African American psychology research include learning style, sense of community and belonging, and spiritualism (Black et al., 2004). . Two famous African American researchers and psychologists are Mamie Phipps Clark and her husband Kenneth Clark. They are best known for their studies of African American children and internalized racism, research that was instrumental in the desegregation case between Brown and the Board of Education. The Clarks applied their research to social services and opened the first child counseling center in Harlem (American Psychological Association, 2019). Listen to the following podcast detailing the Clarks' research and how it affected the Supreme Court decision.

LINK TO LEARN Listen to a podcast ( on the impact of psychological research on an African American in the landmark civil rights case Brown v. Board of Education.

The American Psychological Association has several ethnically based organizations for professional psychologists that facilitate interactions between members. As psychologists belonging to particular ethnic groups or cultures have the greatest interest in studying the psychology of their communities, these organizations provide an opportunity for research to grow on the impact of culture on individual and social psychology.

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1.3 Contemporary Psychology Learning Outcomes By the end of this section you will be able to: • appreciate the diversity of interests and emphases within psychology • understand the basic interests and applications in each of the areas of psychology described • become familiar with some of the majors to make important concepts or figures in each of the areas of psychology described Contemporary psychology is a diverse field, influenced by all the historical perspectives described in the previous section. The diversity of the discipline is reflected in the diversity of the American Psychological Association (APA). The APA is a professional organization representing psychologists in the United States. The APA is the world's largest organization of psychologists, and its mission is to promote and disseminate psychological knowledge for the benefit of people. There are 56 divisions within the APA, representing a variety of disciplines ranging from Societies for the Psychology of Religion and Spirituality to Exercise and Sport Psychology, Behavioral Neuroscience, and Comparative Psychology. Members, Associate Members, and Associate Members reflect the diversity of the field of psychology itself, spanning the spectrum of psychologists from undergraduate to graduate school and from a variety of locations, including educational institutions, the criminal justice system, hospitals, the military, and industry. (American Psychological Association, 2014). The Association for Psychological Science (APS) was founded in 1988 and aims to promote the scientific orientation of psychology. Its formation resulted from disagreements between members of the scientific and clinical branches of psychology within the APA. APS publishes five research journals and is involved in education and advocacy in funding organizations. A significant proportion of its members are international, although the majority are based in the United States. Other organizations provide networking and collaboration opportunities for professionals from different ethnic or racial groups working in psychology, such as the National Latina/o Psychological Association (NLPA), the Asian American Psychological Association (AAPA), the Association of Black Psychologists (ABPsi) and Society of Indian Psychologists (SIP). Most of these groups are also dedicated to the study of psychological and social issues in their respective communities. This section provides an overview of the major subdivisions of contemporary psychology in the order in which they are presented throughout this book. This is not meant to be exhaustive, but it does give an overview of the most important areas of research and practice for modern psychologists.

LINK TO LEARN Visit this website ( to learn more about APA departments. Student resources ( are also provided by the APA.

BIOPSYCHOLOGY AND EVOLUTIONARY PSYCHOLOGY As the name suggests, biopsychology studies how our biology affects our behavior. Although biological psychology is a broad field, many biological psychologists are interested in understanding how the structure and function of the nervous system relates to behavior (Figure 1.11). Thus, they often combine the research strategies of psychologists and physiologists to achieve this goal (as discussed in Carlson, 2013).


Chapter 1 | Introduction to Psychology

Figure 1.11 Biological psychologists study how the structure and function of the nervous system evoke behavior.

Biological psychologists' research interests span a variety of areas, including but not limited to sensory and motor systems, sleep, drug use and abuse, eating behaviors, reproductive behaviors, neurodevelopment, plasticity of the nervous system, and biological correlates of mental disorders. Given the broad areas of interest that fall under the umbrella of biological psychology, it is probably not surprising that people from diverse backgrounds are involved in this research, including biologists, medical scientists, physiologists, and chemists. This interdisciplinary approach is often referred to as neuroscience, which includes biological psychology (Carlson, 2013). While biopsychology typically focuses on proximate causes of behavior based on the physiology of a human or other animal, evolutionary psychology seeks to study the fundamental biological causes of behavior. To the extent that behavior is influenced by genetics, behavior, like any anatomical feature of a human or animal, shows adaptation to its environment. This environment includes the physical environment and, since interactions between organisms can be important for survival and reproduction, the social environment. The study of behavior in the context of evolution originated with Charles Darwin, co-discoverer of the theory of evolution by natural selection. Aware that behaviors must be adaptive, Darwin wrote books entitled The Descent of Man (1871) and The Expression of the Emotions in Man and Animals (1872) to explore this area. Evolutionary psychology, and in particular human evolutionary psychology, has seen a resurgence in recent decades. To be subject to evolution by natural selection, a behavior must have a significant genetic cause. In general, we expect all human cultures to exhibit behavior if it is genetic, since genetic differences between human groups are small. The approach taken by most evolutionary psychologists is to predict the outcome of a behavior in a given situation based on evolutionary theory and then make observations or conduct experiments to see if the results agree with the theory. It is important to realize that these types of studies do not provide strong evidence that a behavior is adaptive because they lack information that the behavior is partly genetic and not wholly cultural (Endler, 1986). Showing that a trait is naturally selected, particularly in humans, is extraordinarily difficult; perhaps for this reason, some evolutionary psychologists are content to assume that the behaviors they study have genetic determinants (Confer et al., 2010). Another disadvantage of evolutionary psychology is that the traits we now possess evolved among us.

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ecological and social conditions a long time ago in human history, and we have little understanding of what those conditions were. This makes it difficult to predict which behavior is adaptive. Behavioral traits need not be adaptive under current conditions, only past conditions when they evolved, which we can only hypothesize about. There are many areas of human behavior that evolution can predict. Examples include memory, mate choice, kinship relationships, friendship and collaboration, parenting, social organization and status (Confer et al., 2010). Evolutionary psychologists have been successful in finding experimental agreement between observations and expectations. For example, in a study of differences in mate preference between men and women that spanned 37 cultures, Buss (1989) found that women ranked potential earning factors higher than men and men ranked potential reproductive factors higher than men and women. (youth and attractiveness) higher than women. partners. In general, the predictions were consistent with evolutionary predictions, although there were discrepancies in some cultures.

SENSATION AND PERCEPTION Scientists interested in both the physiological aspects of sensory systems and the psychological experience of sensory information work in the field of sensation and perception (Figure 1.12). In this regard, sensation and perception research is also quite interdisciplinary. Imagine walking back and forth between buildings when changing from one class to another. You will be flooded with sights, sounds, touches and smells. You also feel the temperature of the air around you and maintain balance as you move. All of these are interesting factors for anyone working in the field of sensation and perception.

Figure 1.12 If you look at this picture, you might see a duck or a rabbit. Sensory information remains the same, but your perception can differ dramatically.

As will be described in a later chapter, which focuses on the results of studies of sensation and perception, our experience of our world is not as simple as the sum of all sensory information (or sensations) combined. Rather, our experience (or perception) is complex and influenced by what we focus our attention on, our past experiences, and even our cultural background.

COGNITIVE PSYCHOLOGY As mentioned in the previous section, the cognitive revolution has led psychologists to turn their attention to a better understanding of the mind and the mental processes underlying behavior. Therefore, cognitive psychology is the field of psychology that focuses on the study of cognitions, or thoughts, and how they relate to our experiences and our actions. Like biological psychology, cognitive psychology is broad and often involves the collaboration of people from different disciplinary backgrounds. This has led some to coin the term cognitive science to describe the interdisciplinary nature of this field of research (Miller, 2003). Cognitive psychologists have research interests that span a wide range of topics, from attention to problem solving to language and memory. Approaches to examining these topics are correspondingly diverse. Given this diversity, cognitive psychology per se is not covered in a chapter of this text; quite different


Chapter 1 | Introduction to Psychology

Concepts related to cognitive psychology are discussed in relevant sections of this text's chapters on Sensing and Perception, Thinking and Intelligence, Memory, Lifespan Development, Social Psychology, and Therapy.

LINK TO LEARN Watch a short video ( that summarizes some of the key concepts studied by cognitive psychologists.

DEVELOPMENTAL PSYCHOLOGY Developmental psychology is the scientific study of development throughout the lifespan. Developmental psychologists are interested in the processes of physical maturation. However, their focus is not limited to physical changes associated with age, as they also focus on changes in cognitive abilities, moral reasoning, social behavior, and other psychological traits. Early developmental psychologists have focused primarily on the changes that occur when reaching adulthood and have provided tremendous insight into the differences in physical, cognitive, and social skills that exist between very young children and adults. For example, research by Jean Piaget (Figure 1.13) has shown that very young children do not exhibit object permanence. Object permanence refers to the understanding that physical things continue to exist even when they are hidden from us. If you show an adult a toy and then hide it behind a curtain, the adult will know that the toy still exists. However, very small babies behave as if a hidden object no longer exists. The age at which object permanence is achieved is somewhat controversial (Munakata, McClelland, Johnson, & Siegler, 1997).

Figure 1.13 Jean Piaget is famous for his theories about the changes in cognitive ability that occur from childhood to adulthood.

While Piaget focused on cognitive changes in infancy and childhood as we move into adulthood, there is growing interest in expanding research to changes that occur much later in life. This may reflect the changing population demographics of developed nations as a whole. As more and more people live longer, the number of people living to old age will continue to rise. In fact, in 2010, it was estimated that just over 40 million people age 65 and older lived in the United States. By 2020, however, that number is expected to increase to around 55 million. It is estimated that by 2050 nearly 90 million people in this country will be aged 65 or older (Department of Health and

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Chapter 1 | Introduction to Psychology


Human Services, undated).

PERSONALITY PSYCHOLOGY Personality psychology focuses on the patterns of thinking and behavior that make each individual unique. Several people (eg, Freud and Maslow) already discussed in our historical overview of psychology, as well as the American psychologist Gordon Allport, contributed to early theories of personality. These early theorists attempted to explain how an individual's personality develops from their perspective. For example, Freud proposed that personality arose when conflicts were waged between the conscious and unconscious parts of the mind throughout life. In particular, Freud theorized that an individual goes through several stages of psychosexual development. According to Freud, the adult personality would result from the resolution of various conflicts centered on the migration of the erogenous zones (or those that produce sexual pleasure) from the oral (mouth) to the anus, from the phallus to the genitals. Like many of Freud's theories, this particular idea was controversial and did not lend itself to experimental testing (Person, 1980). More recently, the study of personality has taken a more quantitative approach. Rather than explaining how personality arises, research focuses on identifying personality traits, measuring those traits, and determining how those traits interact in a given context to determine how a person will behave in a given situation. Personality traits are relatively consistent patterns of thinking and behavior, and many have suggested that five trait dimensions are sufficient to capture observed personality differences in individuals. These five dimensions are known as the "Big Five" or Five Factor Model and include the Conscientiousness, Agreeableness, Neuroticism, Openness, and Extroversion dimensions (Figure 1.14). Each of these traits has been shown to be relatively stable throughout life (e.g. Rantanen, Metsäpelto, Feldt, Pulkinnen & Kokko, 2007; Soldz & Vaillant, 1999; McCrae & Costa, 2008) and influenced by genetics (e.g. B. Jang, Livesly and Vernon, 1996).


Chapter 1 | Introduction to Psychology

Figure 1.14 Each of the dimensions of the five-factor model is represented in this figure. The description provided would describe someone who scores high on that particular dimension. Someone with a lower score on a particular dimension might be described in opposite terms.

SOCIAL PSYCHOLOGY Social psychology focuses on how we interact and relate to others. Social psychologists conduct research on a variety of topics, including differences in how we explain our own behavior versus how we explain the behavior of others, prejudice and attraction, and how we resolve interpersonal conflicts. Social psychologists have also tried to figure out how being around other people changes our own behavior and thought patterns. There are many interesting examples of social psychology research, and you will read about many of them in a later chapter of this book. Until then, you will be introduced to one of the most controversial psychological studies ever conducted. Stanley Milgram was an American social psychologist best known for his research on obedience. In 1961, after the Holocaust, a Nazi war criminal, Adolf Eichmann, was tried on charges of committing mass atrocities. Many people wondered how German soldiers could torture prisoners in concentration camps and were dissatisfied with soldiers' excuses that they were just following orders. At the time, most psychologists agreed that few people would be willing to inflict such extraordinary pain and suffering simply by obeying orders. Milgram decided to do some research to see whether or not this was true (Figure 1.15). As you'll read later in the text, Milgram found that nearly two-thirds of his participants were willing to give another what they thought would be fatal.

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person simply because they have been instructed to do so by an authority figure (in this case, a man in a lab coat). This is despite the fact that the participants were paid simply to attend the research study and could have chosen not to cause pain or more serious consequences to someone else by withdrawing from the study. No one was actually hurt or harmed in any way, Milgram's experiment was a clever ploy that took advantage of research confederates, those who pretend to be participants in a research study who actually work for the researcher and have clear and specific instructions about how to do it behavior during the research study (Hock, 2009). Studies by Milgram and others, which involved deception and potential emotional harm to study participants, catalyzed the development of ethical guidelines for conducting psychological research that discourage deception of research participants unless it can be argued that it will not cause harm. and usually requires informed consent. of the participants.

Figure 1.15 Stanley Milgram's research has shown how far people will go when they obey orders from authority figures. This ad was used to recruit subjects for his research.

INDUSTRIAL ORGANIZATIONAL PSYCHOLOGY Organizational work psychology (I-O psychology) is a subfield of psychology that applies psychological theories, principles, and research to industrial and organizational environments. I-O psychologists are often involved in issues of human resource management, organizational structure and the work environment. Organizations often seek the help of I-O Psychologists to make the best hiring decisions and create an environment conducive to high employee productivity and efficiency. In addition to its applied nature, I-O psychology also involves conducting scientific research on behavior in I-O environments (Riggio, 2013).


Chapter 1 | Introduction to Psychology

HEALTH PSYCHOLOGY Health psychology focuses on how health is influenced by the interaction of biological, psychological, and sociocultural factors. This particular approach is known as the biopsychosocial model (Figure 1.16). Health psychologists are interested in helping individuals achieve better health through public policy, education, intervention, and research. Health psychologists may conduct research examining the relationship between a person's genetic makeup, behavioral patterns, relationships, psychological stress, and health. They can explore effective ways to motivate people to address behavioral patterns that contribute to ill health (MacDonald, 2013).

Figure 1.16 The biopsychosocial model suggests that health/disease is determined by an interaction of these three factors.

SPORT AND EXERCISE PSYCHOLOGY Researchers in sport and exercise psychology study the psychological aspects of sport performance, including motivation and performance anxiety, and the impact of sport on mental and emotional well-being. Similar topics are also researched as it relates to physical activity in general. The course also includes topics broader than sport and exercise, but related to the interactions between mental and physical performance in demanding conditions, such as: B. Firefighters, military operations, artistic performance and surgery.

CLINICAL PSYCHOLOGY Clinical psychology is the branch of psychology concerned with the diagnosis and treatment of mental disorders and other problematic behavioral patterns. As such, it is generally considered a more applied field within psychology; However, some doctors are also actively involved in scientific research. Psychological counseling is a similar discipline that focuses on emotional, social, occupational, and health-related outcomes in individuals considered to be mentally healthy. As noted, both Freud and Rogers provided perspectives that influenced how clinicians engage with people seeking psychotherapy. Although aspects of psychoanalytic theory can still be found in some of today's therapists trained from a psychodynamic perspective, Roger's ideas about client-centered therapy have been particularly influential in the way many clinicians work. Furthermore, both behaviorism and the cognitive revolution shaped clinical practice in the form of behavior therapy, cognitive therapy, and cognitive-behavioral therapy (Figure 1.17). expense

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Chapter 1 | Introduction to Psychology


related to the diagnosis and treatment of mental disorders and problematic behavior patterns are discussed in detail in later chapters of this book.

Figure 1.17 Cognitive-behavioral therapists consider cognitive processes and behaviors when providing psychotherapy. This is one of several strategies that can be employed by practicing clinical psychologists.

This is by far the area of ​​psychology that receives the most attention in the popular media, and many people mistakenly assume that all psychology is clinical psychology.

FORENSIC PSYCHOLOGY Forensic psychology is a branch of psychology that deals with psychological issues as they arise in the context of the judiciary. For example, forensic psychologists (and forensic psychiatrists) assess a person's suitability to stand trial, assess a defendant's mental state, act as attorneys in custody cases, advise on convictions and treatment recommendations, and advise on such matters as eyewitness accounts and child testimonies (American Board of Forensic Psychology, 2014). In these roles, they typically act as expert witnesses, consulted by both sides in a court case to provide their opinions based on research or experience. As experts, forensic psychologists must have a good knowledge of the law and provide information in the context of the legal system and not just in the field of psychology. Forensic psychologists are also used in jury selection and witness preparation. They may also be involved in providing psychological treatment within the criminal justice system. Criminal profilers are a relatively small subset of psychologists who act as consultants to law enforcement agencies.

LINK TO LEARN The APA offers information on careers ( in several areas of psychology.


Chapter 1 | Introduction to Psychology

1.4 Careers in Psychology Learning Outcomes By the end of this section, you will be able to: • Understand the educational requirements for careers in academic settings • Understand the requirements for a career in an academic setting • Understand career options outside of academia Psychologists can working in many different places doing many different things. In general, anyone wishing to pursue a career in psychology at a 4-year college must earn a doctorate in psychology for some majors and at least a master's degree for others. In most fields of psychology, this means earning a PhD in a relevant field of psychology. Literally, PhD refers to a doctorate in philosophy, but here philosophy does not refer to the field of philosophy itself. Rather, philosophy in this context refers to many different disciplinary perspectives that would be housed in a traditional liberal arts and science college. The requirements for a doctorate vary from country to country and even school to school, but typically individuals who earn this degree are required to complete a dissertation. A dissertation is essentially a long research or grouped published article that describes research done as part of doctoral education. In the United States, a dissertation generally must be defended before a review panel before a doctorate can be awarded (Figure 1.18).

Figure 1.18 Doctorates are usually conferred in formal ceremonies involving special attire and rites. (Photo credit: Fort Wainwright Office of Public Affairs)

After someone earns their doctorate, they can apply for a professorship at a college or university. Being on the faculty of a college or university often means splitting time between teaching, research, and service to the institution and work. The time devoted to each of these core functions varies greatly from school to school, and it is not uncommon for faculty to move from location to location to find the best personal fit for different academic environments. The previous section described some of the major areas commonly represented in psychological departments across the country; Thus, depending on the training, a person could be anything from a biological psychologist to a clinical psychologist in an academic setting (Figure 1.19).

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Chapter 1 | Introduction to Psychology


Figure 1.19 People with a doctorate in psychology have a range of job opportunities.

OTHER PROFESSIONAL CAREERS IN ACADEMIC INSTITUTIONS Schools often offer more psychology courses than their full-time professors can teach. In these cases, it is not uncommon to bring in an additional faculty member or faculty member. Associate faculty members and faculty members often have advanced degrees in psychology, but often have primary careers outside of academia and serve in that role as a sideline. Alternatively, they may not have the PhD required by most 4-year institutions and use these opportunities to gain teaching experience. Also, many colleges and 2-year schools require professors to teach their psychology courses. Generally, many of the individuals who pursue careers at these institutions have master's degrees in psychology, although some graduate students also pursue careers at these institutions. Some people pursuing a doctorate enjoy doing research in an academic setting. However, you may not be interested in teaching. These individuals may occupy teaching positions dedicated exclusively to conducting research. Such a position would be more possible in large research-oriented universities. In some areas of psychology, it is common for those who have recently earned their doctoral degrees to seek positions in available postdoctoral training programs before serving as professors. In most cases, young scientists complete one or two postdoctoral programs before applying for a full-time faculty position. Postdoctoral training programs allow young scientists to advance their research programs and expand their research skills under the supervision of other professionals in the field.

CAREER OPTIONS OUTSIDE THE ACADEMIC STRUCTURE Individuals who want to become practicing clinical psychologists have another option of earning a PhD, known as a PsyD. A PsyD is a Doctor of Psychology, which is becoming increasingly popular with individuals interested in pursuing a career in clinical psychology. PsyD programs generally place less emphasis on research-oriented skills and focus more on applying psychological principles in a clinical context (Norcorss & Castle, 2002). Whether earning a PhD or PsyD, in most states, an individual who wants to practice as a licensed clinical or counseling psychologist can undertake postdoctoral research under the supervision of a licensed psychologist. However, in recent years, several states have begun to eliminate this requirement, which would allow earlier entry into the labor market (Munsey, 2009). after one


Chapter 1 | Introduction to Psychology

After the individual meets the state's requirements, their credentials will be evaluated to determine whether they can sit for the license exam. Only individuals who pass this exam can call themselves licensed clinical or counseling psychologists (Norcross, undated). Licensed clinical or consulting psychologists can work in a variety of settings, from private clinical practices to hospital settings. It should be noted that clinical psychologists and psychiatrists do different things and receive different types of training. While both can provide therapy and counseling, clinical psychologists hold a PhD or PsyD, while psychiatrists hold a Doctor of Medicine (MD). As such, licensed clinical psychologists can administer and interpret psychological tests, while psychiatrists can prescribe medication. Doctoral graduates can work in different settings depending on their specialization. For example, someone trained as a biopsychologist might work at a pharmaceutical company to help test the effectiveness of a new drug. Someone with a clinical background can become a forensic psychologist and work within the legal system, making recommendations during criminal trials and parole hearings, or acting as an expert in a court case. While earning a PhD in psychology is a time-consuming process, usually taking between 5 and 6 postgraduate years (DeAngelis, 2010), there are several career paths that can be pursued with a master's degree in psychology. Individuals who wish to provide psychotherapy can obtain a license from several types of professional counselors (Hoffman, 2012). Relevant master's degrees are also sufficient for individuals pursuing careers as school psychologists (National Association of School Psychologists, n.d.), in some sport psychology-related roles (American Psychological Association, 2014), or as consultants in various industrial settings (Landers, 2011, June 14). Bachelor of Psychology programs may be applicable to other careers such as psychiatric social work or psychiatric nursing where assessment and therapy may be part of the job. As mentioned in the opening section of this chapter, a basic education in psychology provides a foundation of knowledge and skills that many employers find very attractive. It should come as no surprise, then, that individuals earning a bachelor's degree in psychology find themselves in a variety of different careers, as shown in Table 1.1. Examples of some of these careers might include working as a case manager, working in sales, working in human resources, and teaching in high schools. The rapidly growing field of health professions is another field where an education in psychology is helpful and sometimes necessary. For example, the Medical College Admission Test (MCAT), which is required for admission to medical school, now includes a section on the psychological basis of behavior. Top Careers for Psychology Graduates (Fogg, Harrington, Harrington & Shatkin, 2012)




Middle and senior management (management, administrator)




social work


Other leadership positions


Human resources (personnel, training)


Other administrative positions


Insurance, real estate, business


marketing and sales

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Chapter 1 | Introduction to Psychology


Top Careers for Psychology Graduates (Fogg, Harrington, Harrington & Shatkin, 2012)




Health Care (Nurse, Pharmacist, Therapist)


Finance (accountant, auditor)

Table 1.1

LINK TO LEARN Watch a short video ( that outlines some of the career opportunities available to those with a bachelor's degree in psychology.


Chapter 1 | Introduction to Psychology

Key terms Professional organization of the American Psychological Association representing psychologists in the United States Behaviorism focuses on observation and control of behavior Biopsychology Study of how biology affects behavior Biopsychosocial model perspective which states that biology, psychology, and social factors interact to determine a clinical-psychological area of ​​an individual's health Psychology focused on diagnosing and treating mental disorders and other problematic behavioral patterns Cognitive psychology Studying cognitions or thoughts and their relationship to experiences and actions Counseling psychology Area of ​​psychology focused on emotional improvement , social, professional and other issues Aspects of the lives of mentally healthy people Developmental psychology scientific study of lifelong development g long dissertation research work research work within the scope of doctoral training method from the empirical a method of acquiring knowledge based on observations, including experience, and not a method based solely on forms of logical reasoning or prior authorities Forensic psychology Field of psychology that the Application of the science and practice of psychology to problems within and related to functionalism of the justice system How mental activities helped an organism adapt to its environment Humanistic perspective within psychology emphasizing the potential for good inherent in all human beings Process of introspection in which one examines one's own conscious experience in order to decompose it into its component parts Make everything a consistent pattern of thinking and behavior The postdoctoral training program allows young scientists to advance their research programs and expand their research skills under the supervision of other professionals in the field and behavior

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Chapter 1 | Introduction to Psychology


PsyD (Doctor of Psychology) PhD that places less emphasis on research-oriented skills and more on the application of psychological principles in a clinical context Sport and exercise psychology area of ​​psychology that focuses on the interactions between mental and emotional factors and physical performance in sport, movement and other activities Structuralism understanding conscious experience through introspection

Summary 1.1 What is psychology? Psychology derives from the roots psyche (meaning soul) and -ology (meaning scientific study of). Thus, psychology is defined as the scientific study of the mind and behavior. Psychology students develop critical thinking skills, become familiar with the scientific method, and recognize the complexities of behavior. 1.2 History of Psychology Before the time of Wundt and James, philosophers were concerned with questions of the mind. However, both Wundt and James helped to create psychology as a distinct scientific discipline. Wundt was a structuralist, which means he believed that our cognitive experience can best be understood by breaking it down into its component parts. He thought this was best accomplished through introspection. William James was the first American psychologist and an advocate of functionalism. This particular perspective focused on how mental activities served as adaptive responses to an organism's environment. Like Wundt, James relied on introspection; however, his research approach also included more objective measures. Sigmund Freud believed that understanding the subconscious was absolutely crucial to understanding conscious behavior. This was especially true of people he saw suffering from various hysterias and neuroses. Freud relied on dream analysis, slips of the tongue and free association as a gateway to the unconscious. Psychoanalytic theory remained a dominant force in clinical psychology for several decades. Gestalt psychology was very influential in Europe. Gestalt psychology takes a holistic view of people and their experiences. When the Nazis came to power in Germany, Wertheimer, Koffka and Koehler emigrated to the United States. Although they left their laboratories and research behind, they introduced Gestalt ideas to America. Some of the principles of Gestalt psychology are still very influential in the study of sensation and perception. One of the most influential schools of thought in the history of psychology was behaviorism. Behaviorism focused on making psychology an objective science by examining overt behavior and downplaying the importance of unobservable mental processes. John Watson is often considered the father of behaviorism, and the contributions of B.F. Skinner for our understanding of the principles of operant conditioning cannot be overemphasized. As behaviorism and psychoanalytic theory embraced so many aspects of psychology, some began to grow dissatisfied with the psychological picture of human nature. Thus, a humanistic movement began to take hold in psychology. Humanism focuses on the potential for good in all people. Both Maslow and Rogers were influential in shaping humanistic psychology. In the 1950s, the landscape of psychology began to change. A behavioral science began to go back to its roots and focus on mental processes. The advent of neuroscience and computer science helped with this transition. Eventually, the cognitive revolution began and people realized that cognition was critical to a true appreciation and understanding of behavior. 1.3 Contemporary Psychology Psychology is a diverse discipline made up of several major subdivisions with unique perspectives.


Chapter 1 | Introduction to Psychology

Biological psychology involves the study of the biological basis of behavior. Sensation and perception refers to the field of psychology that focuses on how information is received by our sensory modalities and how that information is converted into our perceptual experiences of the world around us. Cognitive psychology studies the relationship between thinking and behavior, and developmental psychologists study physical and cognitive changes that occur throughout life. Personality psychology focuses on an individual's unique patterns of behavior, thinking, and emotion. Industrial and organizational psychology, health psychology, sport and movement psychology, forensic psychology and clinical psychology are considered applied areas of psychology. Industrial and organizational psychologists apply psychological concepts to I-O configurations. Health psychologists look for ways to help people lead healthier lives, and clinical psychology involves diagnosing and treating mental disorders and other problem behaviors. Sport and exercise psychologists study the interactions between thoughts, emotions, and physical performance in sport, exercise, and other activities. Forensic psychologists perform psychological activities related to justice. 1.4 Careers in psychology Scientific careers in psychology usually require a doctorate. However, there are several non-academic career opportunities for people with master's degrees in psychology. While those with a bachelor's degree in psychology have more limited psychology-related career options, the skills gained through an undergraduate degree in psychology are useful in a variety of work contexts.

Knowledge review 1. Which of the following skills have been identified for psychology students? one. critical thinking b. Application of the scientific method c. critical evaluation of information sources d. all of the above 2. Psyche is a Greek word meaning ________. one. essence b. soul c. behavior D. Love 3. Before psychology became a recognized academic discipline, people in ________ were concerned with matters of the mind. one. biology b. chemistry c. philosophy D. Physics 4. In the scientific method, a hypothesis is a ________. one. observation b. measurement c. exam d. proposed explanation

5. Based on your reading, which theorist would most likely agree with this statement: Perceptual phenomena are best understood as a combination of their components. one. William James born Max Wertheimer c. Charles Rogers D. Noam Chomsky 6. ________ is best known for proposing his hierarchy of needs. one. Noam Chomsky born Carl Rogers c. Abraham Maslow, the Elder Sigmund Freud 7. Rogers believed that providing genuineness, empathy, and ________ to his clients in the therapeutic setting was critical to their ability to deal with their problems. one. structuralism b. functionalism c. form D. unconditional positive regard

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Chapter 1 | Introduction to Psychology


8. The operant conditioning chamber (also known as a ________ box) is a device used to study the principles of operant conditioning. one. Skinner b. Watson c. Jacob D. Koffka

12. A researcher interested in what factors make an employee better suited for a particular job would likely identify as(n) ________ psychologists. one. B. clinical personality c. social d. AND THE

9. A researcher interested in how changes in cells in the hippocampus (a structure in the brain associated with learning and memory) is related to memory formation would likely identify as(n) ________ psychologists. one. biological b. health c. clinical d. Social

13. If someone wants to be a professor of psychology at a 4-year college, they probably need a ________ degree in psychology. one. Bachelor of Science b. Bachelor of Arts c. promotion master

10. A person's consistent pattern of thinking and behavior is called a ________. one. psychosexual stage b. object permanence c. personality D. Perception 11. In Milgram's controversial obedience study, nearly ________ of the participants were willing to administer apparently fatal electric shocks to another person because an authority figure told them to do so. one. 1/3 b. 2/3 c. 3/4 T. 4/5

14. The ________ places less emphasis on research and more emphasis on the application of therapeutic skills. one. PhD b. PsyD c. Postdoctoral training program d. Dissertation 15. Which of the following degrees would be the minimum required to teach high school psychology courses? one. PhD b. PsyD c. master's d. Bachelor's degree 16. At least a ________ degree is required to practice as a school psychologist. one. employee b. graduation c. doctorate master

Critical Thinking Questions 17. Why do you think psychology courses like this are often a prerequisite for so many different courses? 18. Why do you think many people doubt that psychology is a science? 19. How has the subject of psychology changed over the history of the discipline since the 19th century? 20. To what aspect of psychology was the behaviorist approach to psychology partly a reaction?


Chapter 1 | Introduction to Psychology

21. Given the incredible diversity of the different branches of psychology described in this section, how do they fit together? 22. What possible ethical concerns are associated with Milgram's obedience research? 23. Why is basic training in psychology so useful in many different fields of work? 24. Other than a potentially higher salary, what are the reasons why a person would continue to pursue a psychology degree?

Personal Application Questions 25. Why are you taking this course? What do you hope to learn during this course? 26. Freud is probably one of the best known historical figures in psychology. Where did you find references to Freud or his ideas about the role played by the unconscious in determining conscious behavior? 27. Now that you've been briefly introduced to some of the major areas of psychology, which ones do you most want to learn more about? Because? 28. Which of the career opportunities described in this section do you like best?

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Chapter 2 | psychological research


Chapter 2

psychological research

Figure 2.1 How does TV content affect children's behavior? (Source: work modified by antisocialtory/Flickr)

Chapter Overview 2.1 Why is research important? 2.2 Research approaches 2.3 Analysis of results 2.4 Ethics

Introduction Have you ever wondered if the violence you see on TV affects your behavior? Do you tend to behave aggressively in real life after seeing people on screen behaving violently in dramatic situations? Or does seeing fictional violence actually take the aggression out of your system, making it more peaceful? How are children affected by the media they are exposed to? A psychologist interested in the relationship between behavior and exposure to violent images might ask these same questions. The issue of violence in the media is controversial today. People have always been concerned about the effects of new technologies on our behavior and thought processes. The Greek philosopher Socrates, for example, feared that writing - then a new technology - would affect people's ability to remember because they might rely on written records instead of memorizing information. In our world of rapidly changing technologies, questions about the impact of media are constantly being asked. Many of us have strong opinions on these issues, only to find that the person next to us has the opposite view. How can we find answers that are not supported by mere opinions, but by evidence we can all agree on? Findings from psychological research can help us solve these problems.


Chapter 2 | psychological research

2.1 Why is research important? Learning Outcomes By the end of this section, you will be able to: • explain how scientific research addresses behavioral issues • discuss how scientific research affects public policy • recognize how scientific research can be important for personal decisions Scientific research is a tool crucial to successfully navigating our complex world. Without it, we would be forced to rely solely on intuition, other people's authority, and blind luck. While many of us believe in our ability to decipher and interact with the world around us, history is littered with examples of how wrong we can be when we fail to recognize the need for evidence to support claims. At various points in history, we were certain that the Sun revolved around a flat Earth, that Earth's continents did not move, and that insanity was caused by possession (Figure 2.2). Through systematic scientific research, we eliminate our prejudices and superstitions and gain an objective understanding of ourselves and our world.

Figure 2.2 Some of our ancestors around the world and throughout the ages believed that trepanning - the practice of drilling a hole in the skull, as shown here - allows evil spirits to leave the body and therefore mental illness and other disorders to be dealt with. healed. (Image credit: “taiproject”/Flickr)

The goal of all scientists is to better understand the world around them. Psychologists focus their attention on understanding behavior and the cognitive (mental) and physiological (physical) processes that underlie behavior. Unlike other methods people use to understand the behavior of others, such as intuition and personal experience, the hallmark of scientific research is that there is evidence to support a claim. Scientific knowledge is empirical: it is based on objective, tangible evidence that can be observed again and again, regardless of who is observing. While behavior is observable, the mind is not. When someone cries, we can see the behavior. However, the reason for the behavior is more difficult to determine. Does the person cry because they are sad, in pain or happy? Sometimes we can know the reason for a person's behavior simply by asking a question like: "Why are you crying?" However, there are situations when a person feels uncomfortable or is unwilling to answer the question honestly or is unable to answer it. Babies, for example, could not explain why they cry. In such circumstances, the psychologist must be creative to find ways to better understand the behavior. This chapter examines how scientific knowledge is generated and how that knowledge is important for decisions in our personal lives and in the public sphere.

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USING RESEARCH INFORMATION Trying to determine which theories are accepted by the scientific community and which are not can be difficult, especially in a research field as broad as psychology. More than ever, we have an incredible amount of information at our fingertips, and a simple Internet search on a particular research topic can lead to a host of conflicting studies. In these cases, we see the scientific community going through a process of consensus building, and it may take some time for consensus to emerge. For example, the hypothetical link between exposure to media violence and subsequent aggression has been debated in the scientific community for nearly 60 years. Even today we will encounter criticism, but the consensus is growing. Several professional organizations consider media violence a risk factor for actual violence, including the American Medical Association, the American Psychiatric Association, and the American Psychological Association (American Academy of Pediatrics, American Academy of Child & Adolescent Psychiatry, American Psychological Association, American Medical Association, American Academy of Family Physicians, American Psychiatric Association, 2000). In the meantime, we should strive to think critically about the information we find, using a healthy degree of skepticism. When someone makes a complaint, we should look at it from several different perspectives: what experience does the person making the complaint have, what could he or she stand to gain if the complaint is valid, does the complaint seem justified in the face of the evidence, and what other researchers think to the claim? This is especially important when we consider how much information in advertising campaigns and on the internet claims to be based on "scientific evidence" when in fact it is the belief or perspective of some people trying to sell a product or bring attention to potential customers. We must inform consumers about the information provided to us, as decisions based on this information have significant consequences. This consequence can be seen in politics and public policies. Imagine you were elected governor of your state. One of his responsibilities is to manage the state budget and determine how best to spend his constituents' tax dollars. As the new governor, you must decide whether to use the D.A.R.E. (Drug Abuse Resistance Education) in public schools (Figure 2.3). In this program, officers often enter the classroom to educate students about the dangers of alcohol and other drugs. According to D.A.R.E. website (, this program has been popular since its inception in 1983 and is currently implemented in 75% of school districts in the United States and in more than 40 countries worldwide. Sounds like an easy decision, right? On closer inspection, however, you will find that the vast majority of research on this program consistently suggests that participation has little or no effect on whether or not someone uses alcohol or other drugs (Clayton, Cattarello, & Johnstone, 1996; Ennett , Tobler, Ringwalt & Flewelling, 1994; Lynam et al., 1999; Ringwalt, Ennett & Holt, 1991). If you're striving to be a good steward of taxpayers' money, will you fund this particular program, or will you try to find other programs that research has consistently proven to be effective?

Figure 2.3 The D.A.R.E. The program remains popular in schools around the world, despite research suggesting it is ineffective.


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LINK TO LEARN Watch this story ( to learn more about some of the controversial issues surrounding the D.A.R.E. Program.

Ultimately, it's not just politicians who can benefit from guiding their decisions through polls. We could all consult surveys from time to time when making decisions in our lives. Imagine you've just found out that a close friend has breast cancer or that one of your young relatives has recently been diagnosed with autism. Either way, you want to know which treatment options are most successful with the fewest side effects. How would you find out? You would likely speak with your doctor and personally review the research that has been done on various treatment options - always with a critical eye to ensure you are as informed as possible. Ultimately, research makes the difference between facts and opinions. Facts are observable realities and opinions are personal judgments, conclusions or attitudes that may or may not be accurate. In the scientific community, facts can only be established from evidence gathered through empirical research.

THE PROCESS OF SCIENTIFIC RESEARCH Scientific knowledge advances through a process known as the scientific method. Basically, ideas (in the form of theories and hypotheses) are tested against the real world (in the form of empirical observations), and these empirical observations give rise to other ideas that are tested against the real world, and so on. In this sense, the scientific process is circular. The types of reasoning within the circle are called deductive and inductive. In deductive reasoning, ideas are tested against the empirical world; In inductive reasoning, empirical observations lead to new ideas (Figure 2.4). These processes are inseparable, like breathing in and breathing out, but different research approaches place different emphasis on the deductive and inductive aspects.

Figure 2.4 Psychological research relies on both inductive and deductive reasoning.

In the scientific context, deductive reasoning starts with a generalization – a hypothesis – which is then used to draw logical conclusions about the real world. If the hypothesis is correct, the logical conclusions reached by deductive reasoning must also be correct. A deductive argument might go something like this: All living things require energy to survive (this would be your hypothesis). Ducks are living creatures. Therefore, ducks need energy to survive (logical deduction). In this example, the hypothesis is correct; Therefore, the conclusion is also correct. Sometimes, however, an incorrect hypothesis can lead to a logical but incorrect conclusion. Consider this argument: all ducks are born with it

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Chapter 2 | psychological research


the ability to see. Quackers is a duck. Therefore, Quackers were born with the ability to see. Scientists use deductive reasoning to empirically test their hypotheses. Going back to the duck example, researchers could design a study to test the hypothesis that if all living things require energy to survive, then ducks need energy to survive. Deductive reasoning starts with a generalization that is tested against real-world observations; However, inductive reasoning moves in the opposite direction. Inductive reasoning uses empirical observations to build broad generalizations. Unlike deductive reasoning, conclusions drawn from inductive reasoning may or may not be correct, regardless of the observations on which they are based. For example, you might discover that your favorite fruits—apples, bananas, and oranges—all grow on trees; Therefore, assume that all fruits must grow on trees. This would be an example of inductive reasoning, and the existence of strawberries, blueberries and kiwis clearly shows that this generalization is incorrect, albeit based on a number of direct observations. Scientists use inductive reasoning to formulate theories, which in turn generate hypotheses that are tested using deductive reasoning. Ultimately, science involves both deductive and inductive processes. The case studies, which you'll read about in the next section, for example, are heavily weighted on the side of empirical observations. Therefore, case studies are closely related to inductive processes, as researchers collect large amounts of observations and look for interesting patterns (new ideas) in the data. Experimental research, on the other hand, places great emphasis on deductive reasoning.

LINK TO LEARN Play this interactive Deal Me In card game ( to practice inductive reasoning.

We have established that theories and hypotheses are ideas, but what kind of ideas are they exactly? A theory is a well-developed set of ideas that propose an explanation for observed phenomena. Theories are constantly being compared with the world, but they tend to be too complex to be tested all at once; Instead, researchers create hypotheses to test certain aspects of a theory. A hypothesis is a testable prediction of how the world will behave if our idea is correct, and is usually formulated as an if-then statement (e.g. if I study all night I will pass the test). The hypothesis is extremely important because it bridges the gap between the realm of ideas and the real world. As specific hypotheses are tested, theories are modified and refined to reflect and incorporate the results of these tests. Figure 2.5.


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Figure 2.5 The scientific research method involves formulating hypotheses, conducting research, and creating or modifying theories based on the results.

To see how this process works, let's look at a specific theory and a hypothesis that might arise from that theory. As you will learn in a later chapter, the James-Lange theory of emotion states that emotional experience is based on the physiological arousal associated with the emotional state. If you step outside and discover a very aggressive snake waiting on your doorstep, your heart will race and your stomach will churn. According to James Lange's theory, these physiological changes would lead to your feeling of anxiety. One hypothesis that can be derived from this theory could be that a person who is unaware of the physiological arousal produced by the sight of the snake will not experience fear. A scientific hypothesis is also falsifiable or can be proven wrong. Recall from the introductory chapter that Sigmund Freud had many interesting ideas for explaining various human behaviors (Figure 2.6). A major criticism of Freud's theories, however, is that many of his ideas are unfalsifiable; for example, it is impossible to imagine empirical observations that refute the existence of the id, ego, and superego—the three elements of personality described in Freud's theories. Despite this, because of their historical importance to personality psychology and psychotherapy, Freud's theories are widely taught in introductory psychology texts and remain at the root of all modern forms of therapy.

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Figure 2.6 Many of the peculiarities of (a) Freud's theories, such as (b) his division of the mind into id, ego and superego, have fallen out of favor in recent decades because they are unfalsifiable. More broadly, his views set the stage for much contemporary psychological thinking, such as the unconscious nature of most psychological processes.

In contrast, the James-Lange theory generates falsifiable hypotheses, such as the one described above. Some individuals who suffer significant spinal injuries are unable to feel the physical changes that often accompany emotional experiences. Therefore, we could test the hypothesis by determining how emotional experiences differ between individuals who have the ability to recognize these changes in their physiological arousal and those who do not. Indeed, this research has been done, and although the emotional experiences of people who are unaware of their physiological arousal may be less intense, they still experience emotions (Chwalisz, Diener & Gallagher, 1988). Scientific research's reliance on falsifiability allows for great confidence in the information it produces. By the time information is accepted by the scientific community, it has usually been repeatedly tested.

LINK TO LEARN Visit this website ( to apply the scientific method and practice its steps, using it to solve a mystery, find out why a student is in trouble, and design an experiment to test the color of the house.

2.2 Research approaches Learning outcomes By the end of this section you will be able to: • describe the different research methods used by psychologists • discuss the strengths and weaknesses of case studies, scientific observation, surveys and archival research • longitudinal and cross-sectional research approaches


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Many research methods are available for psychologists to understand, describe, and explain behavior and the cognitive and biological processes that underlie it. Some methods rely on observation techniques. Other approaches involve interactions between researcher and subjects, ranging from a series of simple questions to lengthy in-depth interviews and well-controlled experiments. Each of these research methods has unique strengths and weaknesses, and each method may only be appropriate for certain types of research questions. For example, studies that rely primarily on observation yield incredible amounts of information, but the ability to apply this information to the larger population is somewhat limited due to small sample sizes. Survey research, on the other hand, allows researchers to easily collect data from relatively large samples. While this allows for easier generalization of results to a larger population, the information that can be collected from any survey is somewhat limited and faces problems associated with any type of self-reported data. Some researchers conduct archival searches using existing records. While this can be a reasonably inexpensive way to collect data that can provide insight into a variety of research questions, researchers using this approach have no control over how or what type of data is collected. All methods described so far are correlative in nature. This means that researchers can address important relationships that might exist between two or more variables of interest. However, correlation data cannot be used to make statements about cause and effect relationships. Correlation research can find a relationship between two variables, but the researcher can only state that the relationship between the variables is one of cause and effect when conducting an experiment. In experimental research discussed later in this chapter, there is tremendous control over the variables of interest. While this is a powerful approach, experiments are often conducted in very artificial environments. This calls into question the validity of the experimental results in relation to their application in real environments. Furthermore, many of the questions that psychologists seek to answer cannot be investigated through experimental research for ethical reasons.

CLINICAL OR CASE STUDIES In 2011, The New York Times published an article about Canadian twins Krista and Tatiana Hogan. These particular twins are unique because Krista and Tatiana are conjoined twins joined at the head. There is evidence that the two girls are connected in a part of the brain called the thalamus, which is an important sensory relay centre. Most incoming sensory information is sent through the thalamus before reaching higher regions of the cerebral cortex for processing.

LINK TO LEARN To learn more about Krista and Tatiana, watch this New York Times video ( about their lives.

The implications of this potential connection mean that it may be possible for one twin to experience the sensations of the other twin. For example, if Krista is watching a particularly funny TV show, Tatiana might smile or laugh even though she is not watching the show. This particular possibility has piqued the interest of many neuroscientists trying to understand how the brain uses sensory information. These twins represent a tremendous resource for brain research and, as their condition is so rare, it is likely that scientists will follow these girls closely throughout their lives, as long as their family agrees to share as much of the information received as possible ( Dominicus, 2011).

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In observational research, scientists conduct a clinical or case study when they focus on one person or just a few people. In fact, some scientists spend their entire careers studying just 10 to 20 people. Why should they do this? Obviously, by focusing your attention on a very small number of people, you can gain tremendous insight into these cases. The wealth of information gathered in clinical or case studies is unmatched by any other research method. This allows the researcher to have a very deep understanding of the individuals and the specific phenomenon being studied. If clinical trials or case studies provide so much information, why aren't they more common among researchers? It turns out that the main benefit of this particular approach is also a weakness. As mentioned earlier, this approach is often used when studying individuals who are of interest to researchers because they exhibit a rare trait. Therefore, the people who are the focus of case studies are not like most other people. When scientists want to explain all behavior, focusing attention on a specific group of people can make it difficult to generalize any observations to the larger population as a whole. Generalizability refers to the ability to apply the results of a specific research project to larger sections of society. Again, case studies provide an enormous amount of information, but because the cases are so specific, the potential for applying what has been learned to the average person can be very limited.

NATURAL OBSERVATION If you want to understand how behavior occurs, one of the best ways to gain information is simply to observe behavior in its natural context. However, people can change their behavior in unexpected ways when they know they are being watched. How do researchers get accurate information when people tend to hide their natural behavior? For example, imagine your teacher asks everyone in your class to raise their hands if they always wash their hands after using the restroom. Chances are, almost everyone in the classroom will raise their hands, but do you think washing your hands after every trip to the bathroom is really universal? This is very similar to the phenomenon mentioned earlier in this chapter: many people are uncomfortable answering a question honestly. But if we're serious about finding out the facts about handwashing, we have other options. Suppose we send a classmate to the bathroom to see if everyone washes their hands after using the bathroom. Will our observer blend into the bathroom environment wearing a white coat, sitting with a clipboard and looking at the sinks? We want our researcher to be inconspicuous - perhaps he's standing at one of the sinks pretending to put on contact lenses while secretly recording the relevant information. This type of observational study is called naturalistic observation: observing behavior in its natural environment. To better understand peer exclusion, Suzanne Fanger worked with colleagues at the University of Texas to observe the behavior of preschoolers on a playground. How did the observers remain discreet during the study? They outfitted some of the kids with wireless microphones (which the kids quickly forgot about) and watched as they took notes remotely. Furthermore, children in this particular preschool (a “lab preschool”) were used to having observers on the playground (Fanger, Frankel, & Hazen, 2012). It is crucial that the observer be as inconspicuous and inconspicuous as possible: when people know they are being observed, they behave less naturally. If you have any doubts about this, ask yourself how your driving behavior might differ in two situations: in the first situation, you are driving on a deserted highway in the middle of the day; In the second situation, you are being followed by a police car on the same deserted highway (Figure 2.7).


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Figure 2.7 Seeing a police car behind you would likely influence your driving behavior. (Image credit: Michael Gil)

It should be noted that scientific observation is not limited to human research. In some of the best-known examples of scientific observation, researchers go out to observe different types of animals in their own environment. As in human studies, researchers keep their distance and avoid interfering with test animals so as not to influence their natural behavior. Scientists have used this technique to study social hierarchies and interactions among animals, from squirrels to gorillas. The information provided by these studies is invaluable for understanding how these animals organize themselves socially and communicate with each other. Anthropologist Jane Goodall, for example, has spent nearly five decades observing chimpanzee behavior in Africa (Figure 2.8). Some scientists have criticized Goodall for naming the chimpanzees instead of labeling them with numbers to illustrate the kinds of concerns a researcher might encounter when observing them scientifically. It was believed that the use of names undermined the emotional detachment necessary for objectivity in the study (McKie, 2010).

Figure 2.8 (a) Jane Goodall has made a career of making scientific observations about (b) chimpanzee behavior. (Credit "Jane Goodall": modified work by Erik Hersman; "Chimpanzee": modified work by "Afrika Force"/

The greatest benefit of naturalistic observation is the validity or accuracy of information collected unobtrusively in a natural environment. When individuals behave as they normally would in a given situation, we have a higher level of ecological validity or realism than we could achieve with other research approaches. Therefore, our ability to generalize research results to real-life situations will be improved. When done right, we don't have to worry about people or animals changing their behavior just because they're being watched. People sometimes assume that reality shows give us a glimpse into authentic human behavior. However, the principle of discreet observation is violated, as reality stars are followed by film crews and interviewed for personal confessions in front of the camera. Given this environment, we have to question how natural and realistic their behavior is. The main disadvantage of naturalistic observation is that they are often difficult to set up and control. In our restroom study, what if you were in the restroom all day to record people's handwashing behavior and no one came? Or what if you watched a group of gorillas closely for weeks only to find that they had moved to a new location while you were sleeping in your tent? The advantage of realistic data comes at a price. As a researcher, you have no control over when (or if) you observe behaviors. At the

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Furthermore, this type of observational research usually requires significant investments of time, money and a good deal of luck. Sometimes studies involve structured observations. In these cases, individuals are observed as they engage in specific, specific tasks. An excellent example of structured observation is Mary Ainsworth's Strange Situation (read more about this in the chapter on life development). The Curious Situation is a technique for assessing the attachment styles that exist between a child and a caregiver. In this scenario, caregivers bring their babies into a room full of toys. The awkward situation involves a series of steps, including a stranger entering the room, the caregiver leaving the room, and the caregiver returning to the room. The infant's behavior is closely monitored at each stage, but it is the infant's behavior after reunion with the caregiver that is most predictive in characterizing the infant's attachment style to the caregiver. Another potential problem in observational research is observer bias. In general, individuals who act as observers are intimately involved in the research project and may unconsciously distort their observations to suit their research goals or expectations. To guard against this type of bias, researchers must have clear criteria for the types of behaviors recorded and how these behaviors should be classified. In addition, researchers often compare observations of the same event by multiple observers to test interrater reliability: a measure of reliability that assesses the agreement of observations from different observers.

SURVEYS Psychologists often design surveys as a means of collecting data. Surveys are lists of questions to be answered by survey participants and can be delivered as paper-and-pencil questionnaires, administered electronically, or conducted orally (Figure 2.9). In general, the survey itself can be completed in a short amount of time, and the ease of managing a survey makes it easy to collect data from large numbers of people. Surveys allow researchers to collect data from larger samples than is possible with other survey methods. A sample is a subset of people selected from a population that represents the entire group of people that researchers are interested in. Researchers study the sample and try to generalize their findings to the population.

Figure 2.9 Surveys can be managed in a variety of ways, including electronically managed surveys such as the survey shown here. (Image credit: Robert Nyman)

There are strengths and weaknesses of research compared to case studies. By using surveys, we can collect information from a larger sample of people. A larger sample is better able to reflect the true diversity of the population, allowing for better generalization. Therefore, if our sample is sufficiently large and diverse, we can assume that the data we collect from the survey can be generalized to a larger population with greater certainty than the information collected through a case study. Given the


Chapter 2 | psychological research

With a larger number of people involved, we cannot collect the same depth of information about each person that would be collected in a case study. Earlier in this chapter, we addressed another potential weakness of surveys: people don't always give accurate answers. They might lie, misremember, or answer questions in ways they think look good. For example, people may report that they drink less alcohol than they actually do. By using surveys, any number of survey questions can be answered. A real-world example is the study conducted by Jenkins, Ruppel, Kizer, Yehl, and Griffin (2012) on the backlash against the Arab American community in the US following the September 11, 2001 terrorist attacks. the extent to which this negative attitude toward Arab Americans persisted nearly a decade after the attacks. In one study, 140 survey participants completed a 10-question survey, including questions that went directly to the participant's apparent prejudices toward people of different ethnicities. The survey also asked indirect questions about the likelihood that the participant would interact with a person of a certain ethnicity in different settings (eg, "How likely are you to meet a person of Arab American descent?"). Survey results indicated that participants were unwilling to report prejudiced attitudes toward any ethnic group. However, there were significant differences in their response patterns to questions about social interaction with American Arabs compared to other ethnic groups: They showed less willingness to interact socially with American Arabs compared to other ethnic groups. This suggests that participants harbored subtle forms of prejudice against American Arabs, although they claimed they did not (Jenkins et al., 2012).

ARCHIVE RESEARCH Some researchers gain access to large amounts of data without interacting with a single research participant. Instead, they use existing records to answer various research questions. This type of search approach is called an archive search. Archival research is based on examining past records or datasets to look for interesting patterns or relationships. For example, a researcher can access the academic records of everyone who enrolled in a college over the past ten years and calculate how long it took to graduate, course load, grades, and extracurricular participation. Archival research can provide important information about who is most likely to complete their education and can help identify important risk factors for struggling students (Figure 2.10).

Figure 2.10 A researcher conducting archival research examines records regardless of whether they are archived as (a) paper copies or (b) electronically. (Credit "Paper Files": Modified work by "Newtown Graffiti"/Flickr; "Computer": Modified work by INPIVIC Family/Flickr)

When comparing file search to other search methods, there are several important distinctions. For one thing, the researcher conducting archival research never interacts directly with research participants. Therefore, the time and cost of collecting data for archival research is significantly less. Furthermore, researchers have no control over what information was originally collected. And so,

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Research questions must be tailored so that they can be answered within the framework of existing datasets. There is also no guarantee of consistency between datasets from one source to another, which can make comparing and contrasting different datasets problematic.

LONGITUDINAL AND CROSS-CROSS RESEARCH Sometimes we want to see how people change over time, as in human development and lifespan studies. When we test the same group of people repeatedly over a period of time, we are doing longitudinal research. Longitudinal research is a research project where data collection is carried out repeatedly over a long period of time. For example, we might survey a group of people in their 20s about their eating habits, test them again a decade later at age 30, and again at age 40. Another approach is cross-sectional research. In cross-sectional research, a researcher compares several population groups at the same time. Using the eating habits example above, the researcher can directly compare different groups of people by age. Instead of looking at a group of people over 20 years how their eating habits changed from decade to decade, the researcher would study a group of 20-year-olds and compare them to a group of 30-year-olds and a group of 40-year-olds. Although cross-sectional research requires a short-term investment, it is also limited by existing differences between different generations (or cohorts), which have nothing to do with age per se, but reflect the social and cultural experiences of different individuals who differentiate them from each other. To illustrate this concept, consider the following survey results. There has been a significant increase in popular support for same-sex marriage in recent years. Many studies on this topic divide survey participants into different age groups. In general, younger people are more supportive of same-sex marriage than older people (Jones, 2013). Does this mean that as we age we are less open to the idea of ​​same-sex marriage, or does it mean that older people have different perspectives due to the social climate they grew up in? Longitudinal research is a powerful approach because, over time, the same people will be involved in the research design, which means that researchers need to worry less about differences between cohorts that affect the results of their study. When researching multiple diseases, longitudinal studies are often conducted to understand specific risk factors. These studies usually involve tens of thousands of people who are followed for several decades. Given the large numbers of people involved in these studies, researchers can be confident that their findings can be generalized to a larger population. The Cancer Prevention Study-3 (CPS-3) is one of a series of longitudinal studies sponsored by the American Cancer Society designed to determine predictive risk factors associated with cancer. When participants participate in the study, they answer a questionnaire about their life and family history and provide information about factors that can cause or prevent the development of cancer. Then, every few years, participants will be given more surveys to fill out. In the end, hundreds of thousands of participants will be followed over 20 years to determine which of them get cancer and which don't. Of course, this type of research is important and potentially very informative. For example, previous longitudinal studies sponsored by the American Cancer Society provided some of the first scientific evidence for the now well-established associations between rising cancer rates and smoking (American Cancer Society, undated) (Figure 2.11).


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Figure 2.11 Longitudinal studies such as CPS-3 help us better understand how smoking is associated with cancer and other diseases. (Image credit: CDC/Debora Cartagena)

As with any research strategy, longitudinal research is not without limitations. On the one hand, these studies require an incredible amount of time for both the researcher and the research participants. As some longitudinal studies take years, if not decades, to complete, the results will not be known for a significant amount of time. In addition to the time expenditure, these studies also require a considerable financial investment. Many researchers are unable to allocate the necessary resources to complete a longitudinal project. Research participants must also be willing to continue their participation over an extended period of time, which can be problematic. People move, get married and take new names, get sick and eventually die. Even without significant life changes, some people may simply opt out of the project. As a result, the rates of fluctuation or reduction in the number of research participants due to the discontinuity of longitudinal studies are quite high and increase over the course of a project. For this reason, researchers using this approach often recruit large numbers of participants with the expectation that a significant number will drop out before the end. As the study progresses, they continually check that the sample still represents the larger population and make adjustments if necessary.

2.3 Analyzing Results Learning Objectives By the end of this section you will be able to: • explain what a correlation coefficient tells us about the relationship between variables • recognize that correlation does not indicate a cause and effect relationship between variables • discuss our tendency to look for relationships between variables that don't really exist • Explain random sampling and the assignment of participants to experimental and control groups • Discuss how experimenter or participant bias can affect the results of an experiment • Identify variables ​​independent and dependent Did you know that? Is the sale of ice cream increasing, as is the general crime rate? Is it possible that enjoying your favorite flavor of ice cream could send you on a crime spree? Or do you think that after a crime you might decide to treat yourself to a waffle? There is no doubt that ice cream is related to crime (eg Harper, 2013), but it would be very silly to decide that one actually caused the other. It is much more likely that both ice cream sales and the crime rate depend on the outside temperature. When it's hot, many people go outside, interact, get angry with each other, and sometimes commit crimes. When it's hot outside, we're more likely to reach for a cool treat like ice cream. How do we determine if a relationship really exists?

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between two things? And if there is a relationship, how can we know if it's due to chance or causation?

CORRELATION RESEARCH Correlation means that there is a relationship between two or more variables (e.g., ice cream consumption and crime), but this relationship does not necessarily imply cause and effect. When two variables are correlated, it simply means that when one variable changes, the other changes. We can measure correlation by calculating a statistic known as the correlation coefficient. A correlation coefficient is a number from -1 to +1 that indicates the strength and direction of the relationship between variables. The correlation coefficient is usually represented by the letter r. The numerical part of the correlation coefficient indicates the strength of the connection. The closer the number is to 1 (whether negative or positive), the more closely related the variables are and the more predictable the changes in one variable will be when the other variable changes. The closer the number is to zero, the weaker the relationship and the less predictable the relationships between the variables. For example, a correlation coefficient of 0.9 indicates a much stronger relationship than a correlation coefficient of 0.3. If the variables are unrelated in any way, the correlation coefficient is 0. The ice cream and crime example above is an example of two variables that we might expect to be unrelated. The sign – positive or negative – of the correlation coefficient indicates the direction of the relationship (Figure 2.12). A positive correlation means that the variables are moving in the same direction. In other words, one variable increases when the other increases and, conversely, when one variable decreases, the other decreases. A negative correlation means that the variables are moving in opposite directions. When two variables are negatively correlated, a decrease in one variable is associated with an increase in the other, and vice versa. The example of ice cream and crime rates is a positive correlation as both variables increase as temperatures warmer. Other examples of positive correlations are the relationship between a person's height and weight or the relationship between a person's age and the number of wrinkles. One would expect that there would be a negative association between daytime sleepiness and the number of hours someone slept the night before: the amount of sleep decreases as feelings of sleepiness increase. In a real-life example of a negative correlation, student researchers at the University of Minnesota found a weak negative correlation (r = −0.29) between the average number of days per week that students slept less than 5 hours and their GPA (Lowry , Dean and Manders, 2010). Remember that negative correlation is not the same as no correlation. For example, we probably wouldn't find a correlation between hours of sleep and shoe size. As already mentioned, correlations have predictive value. Imagine that you are on the admissions committee of a large university. They face a huge number of applications, but can only accommodate a small percentage of the applicant pool. How can you decide who to include? You can try to correlate your current students' GPA with their scores on standardized tests like the SAT or ACT. By looking at which correlations were strongest among your current students, you could use this information to predict the relative success of students who applied for university admission.


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Figure 2.12 Scatter plots are a graphical representation of the strength and direction of correlations. The stronger the correlation, the closer the data points are to a straight line. In these examples we see that there is (a) a positive correlation between weight and height, (b) a negative correlation between fatigue and hours of sleep, and (c) no correlation between shoe size and hours of sleep.

LINK TO LEARN Edit this interactive scatter plot ( to practice your understanding of positive and negative correlation.

Correlation Does Not Indicate Causality Correlation research is useful because it allows us to discover the strength and direction of relationships that exist between two variables. However, correlation is limited because establishing the existence of a relationship says little about cause and effect. While variables are sometimes correlated because one causes the other, it could also be that another factor, a confounding variable, is actually causing the systematic movement in our variables of interest. In the ice cream/crime rate example mentioned earlier, temperature is a confounding variable that may explain the relationship between the two variables. Even though we can't point out clear confounding variables, we shouldn't assume that a correlation between two variables implies that one variable causes changes in the other. This can be frustrating when a cause and effect relationship seems clear and intuitive. Recall our discussion of the American Cancer Society's research and how their research projects were among the first demonstrations of the link between smoking and cancer. It seems reasonable to assume that smoking causes cancer, but if we limit ourselves to correlational research, we would be overstepping our bounds with that assumption. Unfortunately, causality as a function of correlations is repeatedly falsely asserted. Such claims are particularly common in advertisements and news. For example, recent research has found that people who eat cereal regularly reach a healthier weight than those who rarely eat cereal (Frantzen, Treviño, Echon, Garcia-Dominic, & DiMarco, 2013; Barton et al., 2005). Guess how cereal companies report this discovery. Does eating cereal really help a person maintain a healthy weight or are there other possible explanations such as diet (Figure 2.13)? While correlation research is invaluable in identifying relationships between variables, a major limitation is the inability to establish causality. Psychologists want to make cause and effect statements, but this can only be done by conducting an experiment to answer a research question. The next section describes how scientific experiments involve methods that eliminate or control for alternative explanations, allowing researchers to study how changes in one variable cause changes in another.

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Figure 2.13 Does eating cereal really make someone a healthy weight? (Image credit: Tim Skillern)

Illusory Correlations The temptation to make false cause-and-effect statements based on correlation research is not the only way we tend to misinterpret data. We also tend to make misleading connections, especially when it comes to unsystematic observations. Spurious correlations, or false correlations, occur when people believe that there are relationships between two things when no such relationship exists. A well-known illusory connection is the supposed effect that the phases of the moon have on human behavior. Many people strongly claim that human behavior is influenced by the phase of the moon and, in particular, that people behave strangely when the moon is full (Figure 2.14).

Figure 2.14 Many people believe that the full moon makes people behave strangely. (Credit: Cory Zanker)

There is no denying that the moon exerts a powerful influence on our planet. The ebb and flow of ocean tides are closely related to the moon's gravitational forces. Many people, therefore, believe it stands to reason that we are also influenced by the moon. After all, our bodies are largely made up of water. However, a meta-analysis of nearly 40 studies has consistently shown that the relationship between the moon and our behavior does not exist (Rotton & Kelly, 1985). Although we pay more attention to unusual behavior during the full moon phase, rates of unusual behavior remain constant throughout the lunar cycle. Why are we so inclined to believe in such illusory correlations? We often read or hear about it and simply accept the information as valid. Or we have a hunch about how something works and then look for evidence to support that hunch, ignoring evidence that would tell us our hunch is wrong; This is called confirmation bias. In other cases, we find illusory correlations based on the information that most easily comes to mind, even when that information is severely limited. And while we're confident we can use these relationships to better understand and predict the world around us, illusory correlations can have significant drawbacks. For example, research suggests that illusory correlations – where certain behaviors are wrongly attributed to certain groups – are involved in the formation of prejudices that can lead to discriminatory behavior (Fiedler, 2004).


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CAUSALITY: PERFORMING EXPERIMENTS AND USING THE DATA As you've learned, the only way to establish a cause and effect relationship between two variables is to conduct a scientific experiment. Experience has a different meaning in the scientific context than in everyday life. In everyday conversations, we often use it to describe trying something for the first time, like trying a new hairstyle or a new food. In a scientific context, however, an experiment has precise design and implementation requirements.

The Experimental Hypothesis To conduct an experiment, a researcher must test a specific hypothesis. As you learned, hypotheses can be formulated through direct observation of the real world or after a careful review of past research. For example, if you think that children should not watch violent television programs because it would lead to more violent behavior, then you have basically hypothesized that watching violent television programs leads to violent behavior makes children behave more violently. How could you have arrived at this particular hypothesis? You might have younger relatives who watch cartoons featuring characters using martial arts to save the world from evildoers, with an impressive array of punches, kicks and defensive stances. You notice that, after watching these programs for a while, your young relatives imitate the fighting behavior of the characters portrayed in the cartoon (Figure 2.15).

Figure 2.15 If you observe such behavior after a child watches violent TV programs, you can lead to the hypothesis that watching violent TV programs leads to an increase in violent behavior. (Image credit: Emran Kassim)

These types of personal observations usually lead us to formulate a specific hypothesis, but we cannot use limited personal observations and anecdotal evidence to rigorously test our hypothesis. To find out whether real-world data supports our hypothesis, we need to conduct an experiment.

Designing an Experiment The most basic experimental design involves two groups: the experimental group and the control group. The two groups are designed the same, except for one difference – experimental manipulation. The experimental group receives the experimental manipulation – that is, the treatment or the variable being tested (in this case, violent television images) – and the control group does not. Since experimental manipulation is the only difference between the experimental and control groups, we can be confident that any differences between the two are due to experimental manipulation and not chance.

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(Video) MODULE 1 The Role of Physical Activity in Managing One's Stress

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In our example of how violent television programs can influence violent behavior in children, we asked the experimental group to watch violent television programs for a specific period of time and then measure their violent behavior. We measured violent behavior in our control group after they watched non-violent television programs for the same amount of time. It is important that the control group is treated similarly to the experimental group, except that the control group does not receive the experimental manipulation. Therefore, we let the control group watch non-violent television programs for the same amount of time as the experimental group. We also need to precisely define or operationalize what counts as violent and non-violent. An operational definition is a description of how we will measure our variables and is important for helping others to understand exactly how and what a researcher is measuring in a given experiment. When operationalizing violent behavior, we can choose to count only physical actions, such as kicking or hitting, as examples of this behavior, or we can also choose to include angry verbal altercations. Whatever we find, it's important that we operationalize violent behavior so that anyone hearing about our study for the first time will know exactly what we mean by violence. This supports people's ability to interpret our data, as well as their ability to repeat our experiment should they choose to do so. Once we have operationalized what counts as violent television programming and violent behavior on the part of our experiment participants, we need to determine how we will conduct our experiment. In this case, we could have participants watch a 30-minute TV program (violent or non-violent, depending on their group affiliation) before sending them to a playground for an hour, where their behavior, number and the type of violent acts are recorded. 🇧🇷 Ideally, the people who observe and record the children's behavior do not know who was assigned to the experimental or control group to control for experimenter bias. Experimenter bias refers to the possibility that a researcher's expectations may distort the results of the study. Remember that conducting an experiment requires a lot of planning, and the people involved in the research project have a vested interest in supporting their hypotheses. If observers knew which child belonged to which group, it might influence how much attention they paid to each child's behavior and how they interpreted that behavior. By being blind to which child is in which group, we protect ourselves from these biases. This situation is a single-blind study, which means that one of the groups (participants) does not know which group it belongs to (experiment or control group), while the researcher who designed the experiment knows which participants are in which group they are. In a double-blind study, both researchers and participants are blind to group assignments. Why would a researcher want to conduct a study where no one knows who is in which group? This allows us to control the expectations of both the experimenter and the participants. If you're familiar with the term placebo effect, you already have an idea why this is an important consideration. The placebo effect occurs when people's expectations or beliefs influence or determine their experience of a particular situation. In other words, just waiting for something to happen can actually make it happen. The placebo effect is commonly described in the context of testing the effectiveness of a new drug. Imagine you work at a pharmaceutical company and you think you have a new drug that is effective in treating depression. To show that your medicine works, do an experiment with two groups: the experimental group receives the medicine and the control group does not. But you don't want participants to know whether or not they received the drug. Why is that? Imagine that you are participating in this study and you have just taken a pill that you think will improve your mood. Since you expect the pill to work, you may feel better just because you took the pill and not because of any real medicine in the pill - this is the placebo effect. To ensure that any mood effects are due to the drug and not anticipation, the control group is given a placebo (in this case, a sugar pill). Now everyone takes a pill and, again, neither the experimenter nor the subjects know who got the drug and who got the sugar pill. Any mood differences between the experimental and control groups can now be attributed to the drug itself rather than the drug.


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Experimenter bias or participant expectations (Figure 2.16).

Figure 2.16 Providing placebo treatment to the control group protects against expectancy bias. (Credit: Elaine and Arthur Shapiro)

Independent and Dependent Variables In a research experiment, we try to study whether changes in one thing cause changes in another. To do this, we need to pay attention to two important variables or things that can be changed in any experimental study: the independent variable and the dependent variable. An independent variable is manipulated or controlled by the experimenter. In a well-designed experimental study, the independent variable is the only important difference between the experimental and control groups. In our example of how violent television programs influence violent behavior in children, the independent variable is the type of program – violent or non-violent – ​​watched by study participants (Figure 2.17). A dependent variable is what the researcher measures to see how much of an effect the independent variable had. In our example, the dependent variable is the number of violent acts committed by the participants.

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Figure 2.17 In an experiment, manipulations of the independent variable are expected to result in changes in the dependent variable. (Automatic weapon credit: Modified work by Daniel Oines; Toy gun credit: Modified work by Emran Kassim)

We expect the dependent variable to change as a function of the independent variable. In other words, the dependent variable depends on the independent variable. A good way to think about the relationship between independent and dependent variables is to ask this question: What is the effect of the independent variable on the dependent variable? Returning to our example, what is the effect of watching half an hour of violent or non-violent television programs on the number of incidents of physical aggression shown on the playground?

Subject Selection and Assignment Once our study has been planned, we need to obtain a sample of subjects to include in our experiment. Our study involves human participants, so we need to determine who to include. Participants are the subjects of psychological research and, as the name suggests, people involved in psychological research actively participate in the process. Psychological research projects often have college students as participants. Indeed, historically, the vast majority of research in subfields of psychology has involved students as research participants (Sears, 1986; Arnett, 2008). But are college students really representative of the general population? College students tend to be younger, better educated, more liberal, and less diverse than the general population. While using college students as test subjects is an accepted practice, relying on such a limited group of research participants can be problematic, as it is difficult to generalize results to a larger population. Our hypothetical experiment involves children, and we must sample child participants first. Samples are used because populations are often too large to reasonably include all members in our particular experiment (Figure 2.18). If possible, we should use random sampling (there are other types of sampling, but for the purposes of this chapter we will focus on random sampling). A random sample is a subset of a larger population in which each member of the population has an equal chance of being selected. Random sampling is preferred because, if the sample is large enough, we can be fairly confident that the participants are representative of the larger population. This means


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that the percentages of the sample characteristics - gender, ethnicity, socioeconomic status and any other characteristics that may affect the results - are close to the percentages of the larger population. For our example, let's say we decide that our interest group is fourth graders. But all fourth graders are a very large population, so we need to be more specific; Rather, we could say that our population of interest is all fourth-grade students in a given city. We must include students from different income brackets, family backgrounds, races, ethnicities, religions and geographic areas of the city. With this population more manageable, we can work with local schools to select a random sample of about 200 fourth graders to participate in our experiment. In summary, since we cannot test all fourth graders in a city, we want to find a group of about 200 that reflects the makeup of that city. With a representative group, we can generalize our results to the larger population without fear of biasing our sample in any way.

Figure 2.18 Researchers can work with (a) a large population or (b) a sample group that is a subset of the larger population. (Public credit: modification of work by James Cridland; Student credit: modification of work by Laurie Sullivan)

Now that we have a sample, the next step in the experimental process is to divide the participants into experimental and control groups by random assignment. With random assignment, all participants have an equal chance of being assigned to one of two groups. There is statistical software that randomly assigns each of the fourth graders in the sample to either the experimental or control group. Randomization is critical to a solid experimental design. With sufficiently large samples, random assignment makes it unlikely that there are systematic differences between groups. For example, it would be very unlikely that we would end up with an all-male group, ethnic identity or religious ideology. This is important because if the groups were systematically different before starting the experiment, we would not know the origin of the differences we found between the groups: were the differences pre-existing or were they caused by manipulation of the independent variables? Random assignment allows us to assume that any observed differences between the experimental and control groups result from manipulation of the independent variables.

LINK TO LEARN Use this online tool ( to instantly generate random numbers and learn more about random sampling and assignment.

Points to Consider Although experiments allow scientists to make cause-and-effect statements, they are not without their problems. Real experiments require the experimenter to manipulate an independent variable, and this can complicate many issues that psychologists may want to address. For example, imagine you want to know

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what effect gender (the independent variable) has on spatial memory (the dependent variable). While you can certainly look for differences between men and women in a task that explores spatial memory, you can't directly control a person's gender. We classify this type of research approach as quasi-experimental and recognize that we cannot make cause-and-effect claims under these circumstances. Experimenters are also constrained by ethical constraints. For example, they could not conduct an experiment to determine whether being abused as a child leads to low self-esteem in adults. To run such an experiment, you would have to randomly assign some experimental participants to an abused group, and such an experiment would be unethical.

Interpretation of Experimental Results Once data have been collected from the experimental and control groups, statistical analysis is performed to find out whether there are significant differences between the two groups. A statistical analysis determines the probability that a difference found is coincidental (and therefore not significant). In psychology, group differences are considered significant or significant when the probability that these differences occurred purely by chance is 5% or less. In other words, if we were to repeat this experiment 100 times, we would expect to find the same results at least 95 times out of 100. The greatest power of experiments is their ability to claim that any significant differences in results were caused by independent variables. This is done because random selection, random assignment, and a design that limits the effects of experimenter bias and participant expectation should create groups that are similar in composition and treatment. So any difference between the groups is due to the independent variable, and now we can finally make a causal statement. If we find that watching a violent TV show leads to more violent behavior than watching a non-violent show, we can safely say that watching violent TV shows leads to an increase in violent behavior.

Research Reports When psychologists complete a research project, they often want to share their findings with other scientists. The American Psychological Association (APA) publishes a manual detailing how to write an article for submission to scientific journals. Unlike an article that might be published in a journal like Psychology Today, which is aimed at a general audience interested in psychology, academic journals generally publish articles from peer-reviewed journals, intended for an audience of professionals and scientists. who are actively involved in research.

LINK TO LEARN The Online Writing Lab (OWL) ( at Purdue University can guide you through the APA writing guidelines.

A peer-reviewed journal article is read by several other scientists (often anonymously) with expertise in the field. These reviewers provide feedback on the quality of the draft to both the author and the journal editor. Reviewers look for strong justification for the research described, a clear description of how the research was conducted, and evidence that the research was conducted ethically. They also look for flaws in the study's design, methods, and statistical analysis. They check whether the conclusions drawn by the authors seem reasonable given the observations made during the research. Reviewers also comment on the value of research in advancing knowledge of the discipline. This helps to avoid unnecessary duplication of research results in the scientific literature and ensures, to some extent, that each research article provides new information. Finally, the journal editor will compile all reviewer comments and determine whether the article will be published.


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published as-is (a rare occurrence), published with revisions, or not accepted for publication. Peer review provides a level of quality control for psychological research. Poorly designed or conducted studies can be discarded, and even well-designed research can be improved with proposed revisions. Peer review also ensures that the research is described clearly enough for other scientists to replicate it, meaning they can repeat the experiment with different samples to determine reliability. Replications sometimes involve additional measures that extend the original finding. In any case, each replication serves to provide more evidence to support the original research results. Successful iterations of published research make scientists more apt to adopt those findings, while repeated failures tend to cast doubt on the legitimacy of the original paper and lead scientists to look elsewhere. For example, it would be a breakthrough in the medical field if a published study suggested that taking a new drug could help people reach a healthy weight without changing their diet. But if other scientists couldn't replicate the results, the original study's claims would be called into question.

DEVELOPING THE AUTISM VACCINE MYTH AND RETRACTION OF PUBLISHED STUDIES Some scientists have claimed that routine childhood vaccinations cause some children to develop autism, and indeed, several peer-reviewed publications have published research that supports these claims. Since the first reports, large-scale epidemiological research has shown that vaccines are not responsible for the development of autism and that it is much safer to vaccinate your child than not to. Additionally, several of the original studies that made this claim have been withdrawn. A published work may be revoked if the data is questioned due to falsification, falsification or serious research design problems. Upon revocation, the scientific community is informed that there are serious problems with the original publication. Retractions may be initiated by the researcher who conducted the study, the research team, the institution that employed the researcher, or the editorial board of the journal in which the article was originally published. In the case of vaccine autism, the withdrawal was due to a significant conflict of interest where the principal investigator had a financial interest in establishing a link between childhood vaccination and autism (Offit, 2008). Unfortunately, the early studies received so much media attention that many parents around the world were reluctant to vaccinate their children (Figure 2.19). For more information on how the vaccine/autism story unfolded and the implications of that story, see Paul Offit's book, Autism's False Prophets: Bad Science, Risky Medicine, and the Search for a Cure.

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Figure 2.19 Some people still think that vaccines cause autism. (Credit: UNICEF Sverige Job Change)

RELIABILITY AND VALIDITY Reliability and validity are two important considerations that must be made in any type of data collection. Reliability refers to the ability to consistently achieve a specific result. In the context of psychological research, this would mean that whatever instruments or tools are used to collect data do so in a consistent and reproducible manner. Unfortunately, a consistent measurement doesn't necessarily mean you've measured something correctly. To illustrate this concept, imagine a kitchen scale being used to measure the weight of the cereal you eat in the morning. If the scale is not properly calibrated, it can constantly underestimate or overestimate the measured amount of grain. Although the scale is very reliable in giving consistent results (for example, the same amount of cereal poured onto the scale gives the same reading every time), these results are incorrect. This is where validity comes into play. Validity refers to the extent to which a given instrument or tool accurately measures what it is intended to measure. While any valid measure is necessarily reliable, the reverse is not necessarily true. Researchers strive to use instruments that are highly reliable and valid.

DAILY CONNECTION How long is the SAT? Standardized tests like the SAT are designed to measure aptitude for college education, but how reliable and meaningful are these tests? Research conducted by the College Board suggests that SAT scores are highly predictive of freshman GPA for college students (Kobrin, Patterson, Shaw, Mattern, & Barbuti, 2008). In this context, predictive validity refers to the test's ability to effectively predict the GPA of freshman students. Given that many colleges require the SAT for admission, this high level of predictive power can be reassuring.


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However, the emphasis on SAT scores in college admissions has sparked controversy on several fronts. On the one hand, some researchers argue that the SAT is a biased test that disadvantages minority students and unfairly reduces their likelihood of admission to college (Santelices & Wilson, 2010). Furthermore, some research has suggested that the predictive validity of the SAT is grossly overstated when it comes to how well it predicts the GPA of freshman college students. Indeed, it has been suggested that the predictive validity of the SAT can be overestimated by up to 150% (Rothstein, 2004). Many colleges are beginning to consider decreasing the importance of SAT scores in admissions decisions (Rimer, 2008). In 2014, College Board Chairman David Coleman expressed his awareness of these issues, acknowledging that college success is more accurately predicted by high school grades than SAT scores. To address these concerns, he called for significant changes to the SAT exam (Lewin, 2014).

2.4 Ethics learning objectives By the end of this section, you will be able to: • discuss how research involving human subjects is regulated • summarize the informed consent and interrogation processes • explain how research involving animals is regulated Today we are Scientists agree that a good research is ethical in nature and guided by a fundamental respect for human dignity and safety. However, as you'll read in the resource box, this wasn't always the case. Modern researchers must demonstrate that the research they carry out is ethical. This section discusses how ethical considerations affect the design and conduct of contemporary research.

RESEARCH INVOLVING HUMAN PARTICIPANTS Any experiment involving human subjects is subject to extensive and strict guidelines designed to ensure that the experiment does not cause harm. Any research facility receiving federal funding for research involving human participants must have access to an Institutional Review Board (IRB). The IRB is a body of individuals, often composed of members of institutional management, academics, and community members (Figure 2.20). The purpose of the IRB is to review research proposals that involve human participants. The IRB will consider these proposals, taking into account the above principles, and IRB approval is usually required for the experiment to proceed.

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Figure 2.20 An institution's IRB meets periodically to review experimental proposals involving human participants. (Credit: Modified work by Lowndes Area Knowledge Exchange (LAKE)/Flickr)

An institution's IRB requires several components in each experiment it authorizes. First, each participant must sign a consent form before participating in the experiment. An informed consent form includes a written description of what participants can expect during the experiment, including potential risks and research implications. It also informs participants that their participation is completely voluntary and can be canceled at any time without penalty. In addition, the declaration of consent guarantees that all data collected in the experiment will be treated with absolute confidentiality. In cases where research participants are under 18 years of age, parents or legal guardians must sign the consent form.

LINK TO LEARN Visit this website ( to view a sample consent form.

Although the informed consent form should describe as honestly as possible what participants will do, deception is sometimes necessary to prevent participants' knowledge of the exact research question from influencing the study results. Cheating involves intentionally deceiving experiment participants to preserve the integrity of the experiment, but not to the point where cheating would be considered harmful. For example, if we are interested in knowing how our opinion of someone is influenced by their clothing, we can use deception when describing the experiment to prevent this knowledge from influencing participants' responses. In cases where deception is involved, participants should receive a full report upon completion of the study - full and honest information about the purpose of the experiment, how the collected data will be used, the reasons why the deception was necessary, and information on how to do this is to study more information.

DIG DEEPER Ethics and the Tuskegee Syphilis Study Unfortunately, current ethical guidelines for research have not always been applied in the past. In 1932, poor rural black sharecroppers from Tuskegee, Alabama were recruited to participate in an experiment conducted by the United States. Public Health Service with the aim of studying syphilis in black men (Figure 2.21). In exchange for free medical care, meals and funeral insurance, 600 men agreed to participate in the study. Just over half of the men tested positive for syphilis and served as an experimental group (since researchers could not randomly assign participants to groups, this is a quasi-experiment). This one


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the remaining individuals free of syphilis served as a control group. However, people who tested positive for syphilis were never told they had the disease. Although there was no treatment for syphilis when the study began, penicillin was recognized as an effective treatment for the disease in 1947. Despite this, participants in this study were not given penicillin and were not allowed to seek treatment at other facilities if the study continued. . Over 40 years, many of the participants unknowingly spread syphilis to their wives (and later to their children born to their wives) and ended up dying because they never received treatment for the disease. This study was stopped in 1972 when the experiment was discovered in the national press (Tuskegee University, undated). The resulting outrage over the experiment led directly to the National Research Act of 1974 and the strict ethical guidelines for human research described in this chapter. Why is this study unethical? How were male participants and their families harmed by this research?

Figure 2.21 A participant in the Tuskegee Syphilis Study receives an injection.

LINK TO LEARN Visit this website ( to learn more about the Tuskegee Syphilis Study.

RESEARCH WITH ANIMALS Many psychologists do research with animals. Often these researchers use rodents (Figure 2.22) or birds as subjects in their experiments—the APA estimates that 90% of all animal experiments in psychology use these species (American Psychological Association, undated). As many basic processes in animals are sufficiently similar to humans, these animals are acceptable surrogates for research that would be considered unethical in human participants.

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Figure 2.22 Rats, like the one shown here, are often used as experimental animals for animal experiments.

This does not mean that animal researchers are immune to ethical concerns. Indeed, the humane and ethical treatment of animal subjects is a critical aspect of this type of research. Researchers must design their experiments to minimize the pain or suffering experienced by the animals serving as guinea pigs. While the IRBs review research proposals involving human participants, animal research proposals are reviewed by an Institutional Animal Care and Use Committee (IACUC). An IACUC consists of institutional administrators, scientists, veterinarians, and community members. This committee is tasked with ensuring that all experimental proposals require humane treatment of animal subjects. It also conducts semiannual inspections of all animal facilities to ensure that research protocols are being followed. No animal testing project can proceed without Committee approval.


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Key Terms Archive research Research method that uses previous records or datasets to answer various research questions or to look for interesting patterns or connections cause and effect relationships in one variable cause the changes in the other variable; can only be determined by an experimental research design clinical or case study study observational research that focuses on one or a few people confirmation bias tendency to ignore evidence that refutes ideas or beliefs variable variable unexpected external factor that affects both variables ​of interest, often giving the wrong impression that changes in one variable cause changes in the other variable, when in fact the external factor causes changes in both variables, the control group serves as a basis for comparison and controls for random factors that may affect study results - keeping such factors above Constant between groups, so experimental manipulation is the only difference between groups Correlation relationship between two or more variables; When two variables are correlated, one variable changes like the other correlation coefficient number from -1 to +1, indicating the strength and direction of the relationship between the variables and is usually represented by r. Cross-sectional research compares various segments of a population in a single debriefing. If an experiment involved fraud, participants are given complete and truthful information about the experiment at the end which the researcher measures to see how much effect the independent variable had. Double-blind study experiment in which both researchers and participants are blind to observed group assignments Large experimental group designed to answer the research question; experimental manipulation is the only difference between the experimental and control groups, so any differences between the two are due to the experimental manipulation and not the random expectations of the experimenter, which distort the results of the study falsifiable refutable by experimental results

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Generalize the conclusion that the results of a sample apply to the larger population influenced or controlled by the experimenter; In a solid experimental study, the independent variable is the only important difference between the experimental and control groups. Inductive conclusions are drawn from observations. Informed consent process, informing a research participant about what to expect during an experiment, the risks involved and the research implications, and then obtaining the individual's consent to participate Institutional Animal Care and Use Committee (IACUC) Committee of administrators, scientists, veterinarians, and community members who review research proposals involving non-human animals Institutional Review Board (IRB) Committee of administrators, scientists, and community members reviewing research proposals involving human participants. measure of agreement between observers on how they record and classify a given event prolonged by period naturalistic observation observation of behavior in its natural environment negative correlation two variables change in different directions, one increasing while the other decreases; A negative correlation is not the same as no correlation. or attitudes that may or may not be true publication placebo effect people's expectations or beliefs influencing or determining their experience in a particular situation population total group of people whom researchers are interested in positive correlation two variables change in the same direction, both will be greater or less random assignment experimental group assignment method, where all participants have an equal chance of being assigned to one of the two groups


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randomly selected subset of a larger population in which each member of the population has an equal chance of being selected Reliability Consistency and reproducibility of a given result Repetition Repeating an experiment with different samples to determine the reliability of the research sample subset of individuals selected from the larger population selected Single-blind study experiment in which the researcher knows which participants are in the experimental group and which are in the control group. Statistical analysis determines the probability that each difference between experimental groups is due to random sampling. The list of questions to be answered by research participants - provided as paper-and-pencil questionnaires, administered electronically, or administered orally - that allows researchers to collect data from large numbers of people is designed to measure

Summary 2.1 Why is research important? Scientists are concerned with explaining and understanding how the world around them works, and they can do this by forming theories that generate hypotheses that are both testable and falsifiable. Theories that stand the test are maintained and refined, while those that do not are discarded or modified. In this way, research allows scientists to separate fact from mere opinion. Having good research information helps us make wise decisions both in public policy and in our personal lives. 2.2 Research Approaches In the clinical study or case study, only a few people are examined over a long period of time. While this approach provides an incredible depth of information, the ability to generalize these observations to the larger population is problematic. Naturalistic observation involves observing behavior in a natural environment and allows valid and realistic information to be collected from realistic situations. However, realistic observation does not allow for much control and usually requires a little time and money to perform. Researchers strive to ensure that their data collection tools are reliable (consistent and reproducible) and valid (accurate). Surveys can be managed in a variety of ways and allow large amounts of data to be collected quickly. However, the depth of information that can be collected through surveys is somewhat limited compared to a clinical trial or case study. In archival research, existing datasets are examined to answer research questions. Longitudinal research has been incredibly useful for researchers who need to gather data about how people change over time. Cross-sectional research compares several segments of a population at the same time. 2.3 Analyzing Results A correlation is described with a correlation coefficient r ranging from -1 to 1. The correlation coefficient tells us something about the nature (positive or negative) and strength of the relationship between two or more variables. Correlations say nothing about causality, no matter how strong the relationship between the variables. In fact, the only way to prove causality is to conduct an experiment. People often make the mistake of claiming that correlations exist when in fact there aren't.

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Researchers can test cause-and-effect hypotheses by conducting experiments. Ideally, experimental participants are randomly selected from the population of interest. Participants will then be randomly assigned to their respective groups. Sometimes the researcher and participants are blinded to group membership to prevent their expectations from influencing the results. In an ideal experimental design, the only difference between experimental and control groups is whether participants are exposed to experimental manipulation. Each group goes through all phases of the experiment, but each group will experience a different level of the independent variables: the experimental group is exposed to experimental manipulation and the control group is not exposed to experimental manipulation. The researcher then measures the changes produced in the dependent variable in each group. Once data is collected from both groups, it is statistically analyzed to determine if there are any significant differences between the groups. Psychologists report their research in peer-reviewed journal articles. Research published in this format is reviewed by a number of other psychologists, who act as filters to separate ideas that are supported by evidence from ideas that are not. Replication plays an important role in ensuring the legitimacy of published research. Only results that can be consistently replicated will gain long-term consensus in the scientific community. 2.4 Ethics Research ethics is an evolving field and some practices that were accepted or tolerated in the past would now be considered unethical. Researchers are expected to follow basic ethical guidelines when conducting experiments involving human participants. Any experiment involving human participants must be approved by an IRB. Participation in experiments is voluntary and requires informed consent from participants. If the experiment involves fraud, each participant should be fully interviewed upon completion of the study. Animal experiments are also subject to a high ethical standard. Researchers who use animals as guinea pigs must design their projects in such a way as to minimize pain and stress. Animal testing requires approval from an IACUC, and all animal facilities are subject to regular inspections to ensure animals are treated humanely.

Control Issues 1. Scientific hypotheses are ________ and falsifiable. one. observable b. originally c. likely d. testable

4. One of the main criticisms of Freud's early theories concerns the fact that his theories ________. one. were very limited in scope b. were very rude c. were too wide d. were not testable

2. ________ are defined as observable realities. one. behavior b. facts c. opinions D. theories

5. Sigmund Freud developed his theory of the human personality by conducting in-depth interviews with a few clients over a period of time. This type of research approach is known as a(n):________. one. File search b. case study c. naturalistic observation d. survey Research

3. Scientific knowledge is ________. one. intuitive b. empirical c. Permanent D. subjective


Chapter 2 | psychological research

6. ________ involves observing the behavior of individuals in their natural environment. one. File search b. case study c. naturalistic observation d. survey Research

12. Longitudinal research is complicated by high rates of ________. one. mistake b. observation c. abrasion D. generalization

7. The major limitation of case studies is ________. one. the superficial nature of the information collected in this approach b. the lack of control the researcher has in this approach c. the inability to generalize the results of this approach to the larger population d. the lack of reliability between raters

13. Height and weight are positively correlated. This means: a. There is no correlation between height and weight. B. Usually, the taller someone is, the thinner they are. ç. Usually, the smaller someone is, the heavier they are. i.e. Weight generally increases with height.

8. The usefulness of observational scientific studies is ________. one. the honesty of data collected in a realistic environment b. how quick and easy these studies are to conduct c. The researcher's ability to ensure that data is collected as efficiently as possible d. the ability to determine cause and effect in this particular approach. 9. Using existing recordings to answer a research question is referred to as ________. one. naturalistic observation b. survey survey c. longitudinal research d. Archival research 10. ________ involves tracking a group of research participants over time. one. File search b. longitudinal survey c. naturalistic observation d. Cross-sectional survey 11. A(n) ________ is a list of questions developed by a researcher that can be maintained on paper. one. file b. case study c. naturalistic observation d. survey Research

14. Which of the following correlation coefficients indicates the strongest relationship between two variables? one. -.90 b. -.50c. +,80d. +0.25 15. Which statement best illustrates a negative correlation between the number of hours you watched television in the week before a test and your test score? one. Too much television leads to poor exam performance. B. Smart students watch less TV. ç. Television interferes with a student's ability to prepare for the upcoming exam. i.e. Students who watch more TV do worse on tests. 16. The correlation coefficient indicates the weakest relationship when ________. one. is the nearest 0b. is closest to -1 c. is positive D. is negative

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Chapter 2 | psychological research

17. ________ means that everyone in the population has an equal chance of participating in the study. one. operationalization b. placebo effect c. random assignment d. Random selection 18. The ________ is controlled by the researcher, while the ________ represents the information collected and statistically analyzed by the researcher. one. dependent variable; independent variable b. independent variable; dependent variable c. Placebo effect; Experimenter bias d. experiment bias; Placebo Effect 19. Researchers should ________ important concepts in their studies so that others can understand exactly how those concepts were defined. one. randomly assign b. choose randomly c. operationalized. generalize 20. Sometimes researchers give control group participants a ________ to control for the effects that participants' expectations may have on the experiment. one. dependent variable b. independent variable c. statistical analysis d. placebo


21. ________ is to animal research what ________ is to human research. one. Consent form; mistake b. IACUC; IRB c. IRB; IACUC d. Illusion; Discussion 22. Researchers may use ________ when providing participants with full details of the experiment, which may influence their responses. one. declaration of consent b. mistake c. ethics D. Discussion 23. An individual's participation in a research project should be ________. one. accidentally b. rewards C. voluntarily d. Audience 24. Before participating in an experiment, subjects must read and sign the ________ form. one. declaration of consent b. interrogation c. IRB D. ethics

Critical Thinking Issues 25. In this section, the D.A.R.E. has been described as an incredibly popular program in schools across the United States, although research consistently suggests that this program is largely ineffective. How to explain this discrepancy? 26. The scientific method is often described as self-correcting and cyclical. Briefly describe your understanding of the scientific method as it relates to these concepts. 27. In this section, conjoined twins Krista and Tatiana were described as possible participants in a case study. In what other circumstances do you think this particular research approach would be particularly useful and why?


Chapter 2 | psychological research

28. It is believed that reality television shows are intended to provide a realistic portrayal of the behavior of characters featured in such shows. This section has shown why this is not really the case. What changes could be made to the way these programs are produced that would result in more honest representations of realistic behavior? 29. Which of the research methods discussed in this section would be most suitable for assessing the effectiveness of the D.A.R.E. Program to prevent the use of alcohol and other drugs? Because? 30. In addition to biomedical research, what other areas of research could greatly benefit from longitudinal and archival research? 31. Earlier in this section, we read about research that suggests there is a link between eating cereal and weight. Grain manufacturers who feature this information in their advertisements could lead one to believe that eating more grains leads to a healthy weight. Why would you make such a claim, and what arguments could you offer to counter this claim of cause and effect? 32. A study was recently published in the journal Nutrition and Cancer that found a negative correlation between coffee consumption and breast cancer. In particular, women who consumed more than 5 cups of coffee a day were found to be less likely to develop breast cancer than women who never consumed coffee (Lowcock, Cotterchio, Anderson, Boucher, & El-Sohemy, 2013). Imagine you see a newspaper article about this research that says "coffee protects against cancer". Why is this title misleading, and why would a more accurate title arouse less interest? 33. Sometimes getting a true random sample can be very difficult. As an alternative, many researchers use convenience samples. For example, a popular convenience sample would include students enrolled in introductory psychology courses. What are the implications of using this sampling technique? 34. Peer review is an important part of publishing research results in many scientific disciplines. This process is usually performed anonymously; In other words, the author of the reviewed article does not know who is reviewing the article and the reviewers do not know the identity of the author. Why should this be an important part of this process? 35. Some argue that animal experimentation is inherently ethically flawed because, unlike human participants, animals do not consent to be involved in research. Do you agree with this perspective? Given that animals do not agree to be involved in research projects, what additional precautions should be taken to ensure that they receive the most humane treatment possible? 36. At the end of the last section, you were asked to design a simple experiment to answer a question of interest. What ethical considerations should be made in your proposed study to ensure that your experiment meets the scientific community's ethical research expectations?

Personal Application Questions 37. Health professionals identify a huge number of health problems associated with obesity, and many people have an understandable desire to reach a healthy weight. There are many diet programs, services and products on the market that help people who want to lose weight. If a close friend is considering purchasing or participating in any of these products, programs or services, how would you ensure that your friend is fully aware of the potential ramifications of that decision? What kind of information would you like to verify before making such an investment or lifestyle change?

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Chapter 2 | psychological research


38. A friend of yours works part time at a local pet store. Increasingly interested in how dogs normally communicate and interact with each other, your friend is considering visiting a local veterinary clinic to see how dogs interact in the waiting room. After reading this section, do you think this is the best way to better understand these interactions? Do you have any suggestions that might lead to more valid data? 39. As a college student, you are no doubt concerned about the grades you are getting as you complete your coursework. If you were interested in how overall GPA is related to success in life after college, how would you approach that question and what kind of resources would you need to conduct this research? 40. We all tend to make illusory correlations from time to time. Try to think of an illusory correlation held by you, a family member, or a close friend. How do you think this illusory correlation came about and what can be done about it in the future? 41. Is there a question about human or animal behavior that you would like answered? Make a hypothesis and briefly describe how you would conduct an experiment to answer your question. 42. Take a few minutes to reflect on all the advances our society has made through animal research. How did you, a friend or family member directly benefit from this type of research?


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Chapter 3 | biopsychology


Chapter 3


Figure 3.1 Different brain imaging techniques give scientists insight into different aspects of how the human brain works. From left to right, PET scan (positron emission tomography), computed tomography (computed tomography), and fMRI (functional magnetic resonance imaging) are three types of scans. (Left source: Modified work from Department of Health and Human Services, National Institutes of Health; Center source: Modified work from Aceofhearts1968/Wikimedia Commons; Right source: Modified work from Kim J, Matthews NL, Park S .)

Chapter Overview 3.1 Human Genetics 3.2 Cells of the Nervous System 3.3 Parts of the Nervous System 3.4 Brain and Spinal Cord 3.5 The Endocrine System

Introduction Have you ever taken a device apart to find out how it works? Many of us have done this, either to try to fix it or simply to satisfy our curiosity. The inner workings of a device often differ from its external user interface. For example, we don't think about microchips and circuits when we turn up the volume on a cell phone; Instead, we thought about getting the volume right. Likewise, the internal functioning of the human body often differs from the external expression of that functioning. It is the psychologists' job to find the connection between them - for example, to discover how the firing of millions of neurons becomes a thought. This chapter attempts to explain the biological mechanisms underlying behavior. These physiological and anatomical foundations are the basis for many areas of psychology. In this chapter, you will learn how genetics affect physiological and psychological traits. You will learn about the structure and function of the nervous system. And finally, you'll learn how the nervous system interacts with the endocrine system.


Chapter 3 | biopsychology

3.1 Human genetics learning goals By the end of this section you will be able to: • explain the basic principles of the theory of evolution through natural selection • describe the differences between genotype and phenotype • discuss how gene-environment interactions are crucial for expression Physical and Psychological Traits Psychologists study genetics to better understand the biology that contributes to certain behaviors. Although all humans share certain biological mechanisms, we are all unique. And although our bodies have many of the same parts – brains, hormones and cells with genetic codes – they express themselves in a variety of behaviors, thoughts and reactions. Why do two people infected with the same disease have different outcomes: one survives and the other succumbs to the disease? How are genetic diseases passed down family lines? Are there genetic components to mental illnesses like depression or schizophrenia? To what extent can health problems like childhood obesity have a psychological basis? To explore these questions, let's first focus on a specific disease, sickle cell anemia, and how it can affect two infected sisters. Sickle cell anemia is a genetic disease in which red blood cells, which are normally round, take on a crescent shape (Figure 3.2). The altered shape of these cells affects their function: the sickle-shaped cells can clog blood vessels and block blood flow, causing a high fever, severe pain, swelling and tissue damage.

Figure 3.2 Normal blood cells travel freely through blood vessels, while sickle-shaped cells form blockages that impede blood flow.

Many people with sickle cell disease – and the specific genetic mutation that causes it – die early. While the notion of "survival of the fittest" might suggest that people suffering from this disease have a low survival rate and therefore the disease is becoming less common, this is not the case. Despite the negative evolutionary implications associated with this genetic mutation, the sickle cell gene remains relatively common in people of African descent. Why is this? The explanation is illustrated with the following scenario. Imagine two young women - Luwi and Sena - sisters in rural Zambia, Africa. Luwi carries the sickle cell gene; Sena does not carry the gene. Sickle cell carriers have one copy of the sickle cell gene but do not have full sickle cell anemia. They only show symptoms when they are severely dehydrated or lacking oxygen (such as when climbing a mountain). Carriers are believed to be immune to malaria

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Chapter 3 | biopsychology


(an often fatal disease widespread in tropical climates) because changes in blood chemistry and immune function prevent the malaria parasite from being effective (Gong, Parikh, Rosenthal, and Greenhouse, 2013). However, full sickle cell disease with two copies of the sickle cell gene does not provide immunity to malaria. On their way home from school, the two sisters are bitten by mosquitoes that carry the malarial pathogen. Luwi does not contract malaria because she carries the sickle cell mutation. Sena, on the other hand, contracted malaria and died just two weeks later. Luwi survives and eventually has children to whom she can pass the sickle cell mutation.

LINK TO LEARN Visit this website ( to learn more about how a DNA mutation leads to sickle cell anemia.

Malaria is rare in the United States, so the sickle cell gene is good for nobody: the gene manifests itself mainly in health problems - minor in carriers, severe in developed disease - with no health benefits for carriers. In other parts of the world, however, the situation is quite different. In parts of Africa where malaria is common, the sickle cell mutation offers health benefits to carriers (protection against malaria). This is exactly the situation described by Charles Darwin in the theory of evolution by natural selection (Figure 3.3). Simply put, the theory states that organisms that are best suited to their environment survive and reproduce, while those that are least suited to their environment die. In our example, we can see that Luwi's mutation is highly adaptable as a carrier in her African homeland; However, if she lived in the United States (where malaria is much less common), mutating her could be costly—with a high probability of the disease in her children and minor health problems of her own.

Figure 3.3 (a) In 1859, Charles Darwin presented his theory of evolution by natural selection in his book On the Origin of Species. (b) There is only one illustration in the book: this diagram showing how species evolve over time through natural selection.


Chapter 3 | biopsychology

GO FURTHER Two Perspectives on Genetics and Behavior It's easy to confuse two fields that study the interaction of genes with the environment, such as evolutionary psychology and behavioral genetics. How can we tell them apart? In both areas, it is assumed that genes not only encode certain properties, but also contribute to certain patterns of perception and behavior. Evolutionary psychology focuses on how universal patterns of behavior and cognitive processes have evolved over time. Therefore, variations in cognition and behavior would make individuals more or less successful in reproducing and transmitting these genes to their offspring. Evolutionary psychologists study a variety of psychological phenomena that may have evolved as adaptations, including fear responses, food preferences, mate choice, and cooperative behavior (Confer et al., 2010). Whereas evolutionary psychologists focus on universal patterns that have evolved over millions of years, behavioral geneticists study how individual differences arise in the present through the interaction of genes and environment. When studying human behavior, behavioral geneticists often use twinning and adoption studies to explore interesting questions. Twin studies compare the rates at which a specific behavioral trait is shared between identical and dizygotic twins; Adoption studies compare these rates between biologically related relatives and adoptive relatives. Both approaches offer some insight into the relative importance of genes and environment in the expression of a particular trait.

LINK TO LEARN Watch this interview ( with renowned evolutionary psychologist David Buss to explain how a psychologist approaches evolution and how this approach is used in the field of social sciences .

GENETIC VARIATION Genetic variation, the genetic difference between individuals, helps a species adapt to its environment. In humans, genetic variation begins with one egg, about 100 million sperm, and fertilization. Fertile women ovulate about once a month, releasing an egg from follicles in the ovary. During the journey of the egg from the ovary through the fallopian tubes to the uterus, a sperm can fertilize an egg. The egg and sperm each contain 23 chromosomes. Chromosomes are long chains of genetic material known as deoxyribonucleic acid (DNA). DNA is a helical molecule made up of base pairs of nucleotides. On each chromosome, DNA sequences make up genes that control, or partially control, a series of visible characteristics known as traits, such as eye color, hair color, etc. A single gene can have several possible variations or alleles. An allele is a specific version of a gene. Thus, a given gene can encode the trait of hair color, and the different alleles of that gene affect an individual's hair color. When a sperm and egg fuse, their 23 chromosomes pair up, forming a zygote with 23 pairs of chromosomes. Therefore, each parent contributes half of the genetic information carried by the offspring; The resulting physical characteristics of the offspring (called the phenotype) are determined by the interaction of the genetic material provided by the parents (called the genotype). A person's genotype is that person's genetic makeup. The phenotype, on the other hand, refers to the individual's inherited physical traits, which are a combination of genetic and environmental influences (Figure 3.4).

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Figure 3.4 (a) Genotype refers to the genetic makeup of an individual, based on the genetic material (DNA) inherited from the parents. (b) The phenotype describes the observable characteristics of an individual, such as hair color, skin color, height, and build. (credit a: work modification by Caroline Davis; credit b: work modification by Cory Zanker)

Most traits are controlled by multiple genes, but some traits are controlled by one gene. A trait like a cleft chin is influenced by a single gene from each parent. In this example, we will name the cleft chin gene "B" and the smooth chin gene "b". The cleft chin is a dominant trait, which means that the presence of the dominant allele from one parent (Bb) or from both parents (BB) will always result in the phenotype associated with the dominant allele. If someone has two copies of the same allele, they are said to be homozygous for that allele. If someone has a combination of alleles for a specific gene, they are said to be heterozygous. For example, flat chin is a recessive trait, meaning that an individual will only exhibit the flat chin phenotype if they are homozygous for that recessive allele (bb). Imagine a woman with a cleft chin marrying a man with a clean chin. What kind of chin will your child have? The answer to this depends on which alleles each parent carries. If the female is homozygous for cleft chin (BB), her offspring will always have cleft chin. However, things get a little more complicated if the mother is heterozygous for this gene (Bb). Since the parent has a smooth chin—homozygous for the recessive allele (bb)—we can assume that the offspring have a 50% chance of having a cleft chin and a 50% chance of having a smooth chin (Figure 3.5).

Figure 3.5 (a) A Punnett square is a tool used to predict how genes will interact in the production of offspring. The big B represents the dominant allele and the small b for the recessive allele. In the cleft chin example, where B is the cleft chin (dominant allele), you can expect a cleft chin phenotype whenever a pair contains the dominant allele B. You can expect a smooth chin phenotype only when two copies of the recessive bb allele are present. (b) A cleft chin, shown here, is a hereditary trait.

Sickle cell anemia is just one of many genetic disorders caused by the pairing of two recessive genes. For example, phenylketonuria (PKU) is a condition in which people lack an enzyme that converts normally harmful amino acids into harmless by-products. If someone with this condition goes untreated, he or she will experience significant deficits in cognitive function, seizures, and an increased risk of various disorders.


Chapter 3 | biopsychology

Mental Disorders, Mental Disorder. Because PKU is a recessive trait, each parent must have at least one copy of the recessive allele to produce a child with the disease (Figure 3.6). So far we've discussed traits that affect only one gene, but few human traits are controlled by a single gene. Most traits are polygenic: they are controlled by more than one gene. Height is an example of a polygenic trait, as are skin color and weight.

Figure 3.6 In this Punnett square, N represents the normal allele and p represents the recessive allele associated with PKU. When two individuals mate, both heterozygous for the PKU-associated allele, their offspring have a 25% chance of expressing the PKU phenotype.

Where do the harmful genes that contribute to diseases like PKU come from? Genetic mutations provide a source of harmful genes. A mutation is a sudden and permanent change in a gene. While many mutations can be harmful or fatal, every now and then a mutation benefits a person, giving them an advantage over those who don't have the mutation. Remember that the theory of evolution states that individuals best adapted to their specific environment are more likely to reproduce and pass their genes on to future generations. For this process to occur, there must be competition – more specifically, there must be variability in the genes (and the resulting traits) that allow for variation in environmental adaptability. If a population consisted of identical individuals, dramatic changes in the environment would affect everyone equally and there would be no difference in selection. In contrast, the diversity of genes and associated traits allows some individuals to perform slightly better than others in the face of environmental change. This creates a distinct advantage for individuals who are best suited to their environment in terms of successful reproduction and genetic transmission.

GENE-ENVIRONMENT INTERACTIONS Genes do not exist in a vacuum. While we are all biological organisms, we also exist in an environment that is incredibly important in determining not just when and how our genes are expressed, but in what combination. Each of us represents a unique interaction between our genetic makeup and our environment; The reaction domain is one way to describe this interaction. The Response Zone asserts that our genes define the boundaries within which we can act, and our environment interacts with genes to determine where we fall in this zone. For example, if a person's genetic makeup predisposes them to high levels of intellectual potential and they are raised in a rich and stimulating environment, they are more likely to reach their full potential than if they were raised in conditions of significant deprivation. .

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According to the reaction zone concept, genes set clear limits to potential, and the environment determines how much of that potential is achieved. Some disagree with this theory, arguing that genes do not limit a person's potential. Another perspective on the interaction between genes and the environment is the concept of environmental genetic correlation. Simply put, our genes affect our environment, and our environment affects the expression of our genes (Figure 3.7). Our genes and the environment not only interact as in the reaction area, but also influence each other bidirectionally. For example, the son of an NBA player would likely be introduced to basketball at a young age. Such exposure can allow the child to reach their full athletic and genetic potential. Thus, the parental genes shared by the child influence the child's environment, and that environment, in turn, is suited to sustaining the child's genetic potential.

Figure 3.7 Nature and nurture work together like complex pieces of a human puzzle. The interplay of environment and genes makes us the individual we are. ("Puzzle" credit: modified work by Cory Zanker; "Houses" credit: modified work by Ben Salter; "DNA" credit: modified work by NHGRI)

In a different approach to gene-environment interactions, the field of epigenetics looks beyond the genotype itself and examines how the same genotype can be expressed in different ways. In other words, researchers are studying how the same genotype can lead to very different phenotypes. As mentioned earlier, gene expression is often influenced by environmental context in ways that are not entirely obvious. For example, identical twins share the same genetic information (identical twins develop from a single fertilized egg, which splits so the genetic material in each is exactly the same; in contrast, fraternal twins develop from from two different eggs, produced by different sperm). fertilized so that the genetic material varies as in non-twin siblings). But even with identical genes, there remains incredible variability in how gene expression can develop over the lifetime of each twin. Sometimes one twin develops a disease and the other does not. In one example, Tiffany, an identical twin, died of cancer at age 7, but her twin, who is now 19, never had cancer. Although these individuals share an identical genotype, their phenotypes differ in how this genetic information is expressed over time. The epigenetic perspective is very different from the response range because here the genotype is not fixed and limited.

LINK TO LEARN Visit this site ( for an engaging video base on the epigenetics of twin studies.

Genes affect more than our physical characteristics. In fact, scientists have found genetic links to it.


Chapter 3 | biopsychology

a set of behavioral traits ranging from basic personality traits to sexual orientation and spirituality (see, for example, Mustanski et al., 2005; Comings, Gonzales, Saucier, Johnson & MacMurray, 2000). Genes are also linked to temperament and a range of mental disorders such as depression and schizophrenia. So while it's true that genes provide the biological blueprints for our cells, tissues, organs and bodies, they also have a significant impact on our experiences and behavior. Consider the following findings about schizophrenia in light of our three perspectives on gene-environment interactions. Which view do you think best explains this evidence? In a study of people placed for adoption, adoptees whose birth mothers had schizophrenia and who grew up in a dysfunctional family environment were much more likely than any other group in the study to develop schizophrenia or another psychotic disorder: • From adopters whose birth mothers suffered of schizophrenia (high genetic risk) and who grew up

in disturbed family environments, 36.8% likely developed schizophrenia. • From adopters whose biological mothers suffered from schizophrenia (high genetic risk) and who grew up

In healthy family environments, 5.8% were likely to develop schizophrenia. • From adoptees who were and were at low genetic risk (whose mothers did not have schizophrenia).

5.3% who grew up in a disturbed family environment likely developed schizophrenia. • From adoptees who were and were at low genetic risk (whose mothers did not have schizophrenia).

4.8% of children raised in a healthy family environment were likely to develop schizophrenia (Tienari et al., 2004). The study shows that adoptees with a high genetic risk develop schizophrenia only if they grow up in a disturbed home environment. This research lends credence to the notion that both genetic susceptibility and environmental stress are necessary for the development of schizophrenia and that genes alone do not tell the whole story.

3.2 Cells of the Nervous System Learning Objectives By the end of this section you will be able to: • identify the basic parts of a neuron • describe how neurons communicate • explain how drugs act as agonists or antagonists for a specific neurotransmitter system understand the human mind to understand, can study the nervous system. Learning how cells and organs (such as the brain) work helps us understand the biological basis behind human psychology. The nervous system is made up of two basic types of cells: glial cells (also known as glia) and neurons. Traditionally, glial cells, which outnumber neurons ten to one, have been thought to play a supportive role for neurons, both physically and metabolically. Glial cells provide a scaffolding on which the nervous system is built, help neurons align to allow for neuronal communication, insulate neurons, transport nutrients and waste products, and mediate immune responses. Neurons, on the other hand, act as interconnected information processors that are essential for all nervous system tasks. This section briefly describes the structure and function of neurons.

NEURON STRUCTURE Neurons are the central building blocks of the nervous system, which is 100 billion people at birth. Like all cells, neurons are composed of many different parts, each performing a specialized function (Figure 3.8). The outer surface of a neuron consists of a semipermeable membrane. This membrane allows smaller molecules to

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Chapter 3 | biopsychology


and uncharged molecules pass while larger or highly charged molecules are stopped.

Figure 3.8 This figure shows a prototype neuron being myelinated.

The nucleus of the neuron is located in the soma or cell body. The soma has branched extensions known as dendrites. The neuron is a small information processor and the dendrites serve as entry points where signals from other neurons are received. These signals are transmitted electrically through the soma and along a large length of the soma known as an axon, which terminates in several terminal buds. The end buds contain synaptic vesicles that house neurotransmitters, the nervous system's chemical messengers. Axons vary in length from a fraction of an inch to several feet. In some axons, glial cells form a fatty substance known as a myelin sheath that surrounds the axon and acts as an insulator, increasing the speed with which the signal travels. The myelin sheath is critical for the normal functioning of neurons in the nervous system: loss of the insulation it provides can impair normal functioning. To understand how this works, let's look at an example. Multiple sclerosis (MS), an autoimmune disease, involves widespread loss of the myelin sheath in axons throughout the nervous system. The resulting disturbance in the electrical signal prevents neurons from transmitting information quickly and can lead to a range of symptoms, including dizziness, fatigue, loss of motor control and sexual dysfunction. While some treatments can help change the course of the disease and manage certain symptoms, there is currently no known cure for multiple sclerosis. In healthy individuals, the neuronal signal travels rapidly down the axon to the terminal knobs, where synaptic vesicles release neurotransmitters into the synapse (Figure 3.9). The synapse is a very small space between two neurons and is an important place where communication between neurons takes place. Once neurotransmitters are released at the synapse, they travel across the tiny gap and bind to corresponding receptors on the dendrite of a neighboring neuron. Receptors, proteins on the cell surface to which neurotransmitters bind, vary in shape, with different shapes "snapping" different neurotransmitters. How does a neurotransmitter “know” which receptor to bind to? The neurotransmitter and receptor have what is called a lock and key relationship - specific neurotransmitters fit specific receptors, just as a key fits a lock. The neurotransmitter will bind to whatever receptor it matches.


Chapter 3 | biopsychology

Figure 3.9 (a) The synapse is the space between the end knob of one neuron and the dendrite of another neuron. (b) In this pseudocolor scanning electron microscope image, one end bud (green) has been opened to reveal the synaptic vesicles (orange and blue) inside. Each vesicle contains about 10,000 neurotransmitter molecules. (Credit b: modification of work by Tina Carvalho, NIH-NIGMS; scale bar data by Matt Russell)

NEURAL COMMUNICATION Now that we understand the basic structures of the neuron and the role these structures play in neural communication, let's take a closer look at the signal itself - how it travels through the neuron and then jumps to the next neuron, where the process is repeated. . We start at the neural membrane. The neuron exists in a fluid environment - it is surrounded by extracellular fluid and contains intracellular fluid (i.e., cytoplasm). The neuronal membrane keeps these two fluids separate—a crucial role, as the electrical signal that passes through the neuron depends on whether the intracellular and extracellular fluids are electrically different. This difference in charge across the membrane, called the membrane potential, provides energy for the signal. The electric charge of liquids is caused by charged molecules (ions) dissolved in the liquid. The semipermeable nature of the neuronal membrane somewhat restricts the movement of these charged molecules, and as a result, some of the charged particles tend to become more concentrated inside or outside the cell. Between signals, the membrane potential of the neuron is maintained in a ready state called the resting potential. Like a taut rubber band waiting to spring into action, the ions line up on either side of the cell membrane, ready to cross the membrane when the neuron becomes active and the membrane opens its gates (i.e., a sodium-potassium pump that allows movement of ions across the membrane). Ions in areas of high concentration are ready to move into areas of low concentration and positive ions are ready to move into areas of negative charge. In the resting state, sodium (Na+) is in greater concentration outside the cell, so it tends to enter the cell. Potassium (K+), on the other hand, is more concentrated inside the cell and tends to migrate out of the cell (Figure 3.10). Also, the inside of the cell is slightly negatively charged compared to the outside. This exerts an additional force on the sodium, causing it to enter the cell.

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Figure 3.10 At the resting potential, Na+ (blue pentagons) is more concentrated outside the cell in the extracellular fluid (shown in blue), while K+ (purple squares) is more concentrated closer to the membrane in the cytoplasm or intracellular fluid. Other molecules, such as chloride ions (yellow circles) and negatively charged proteins (brown squares), contribute a net positive charge to extracellular fluid and a net negative charge to intracellular fluid.

The neuron receives a signal from this potential resting state and its state changes abruptly (Figure 3.11). When a neuron receives signals at its dendrites – due to the binding of neurotransmitters from a neighboring neuron to its receptors – tiny pores, or gates, in the neuronal membrane open, allowing Na+ ions, driven by differences in charge and concentration, to enter the cell. This influx of positive ions makes the internal charge of the cell more positive. When this charge reaches a certain level called the excitation threshold, the neuron becomes active and the action potential begins. Many more pores open, resulting in a massive influx of Na+ ions and a huge positive spike in the membrane potential, the action potential. At the peak of the peak, the sodium gates close and the potassium gates open. When positively charged potassium ions escape, the cell rapidly begins repolarization. First it hyperpolarizes, becoming slightly more negative than the resting potential, and then it levels out and returns to the resting potential.

Figure 3.11 During the action potential, the electrical charge across the membrane changes dramatically.

This positive spike represents the action potential: the electrical signal that normally travels from the cell body down the axon to the axon terminals. The electrical signal travels down the axon as a wave; At each point, some of the sodium ions entering the cell diffuse into the next segment of the axon, increasing the charge above the excitation threshold and triggering a new influx of sodium ions. The action potential moves everything


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the path of the axon to the terminal buds. The action potential is an all-or-nothing phenomenon. Simply put, this means that an input signal from another neuron is either sufficient or insufficient to reach the excitation threshold. There is no in-between and there is no way to turn off an action potential once it has started. Think of it like sending an email or a text message. You can remember to send whatever you want, but the message won't be sent until you click the send button. What's more, once you send the message, there's no stopping it. Because it is all or nothing, the action potential is regenerated or propagated in full force at any point along the axon. Much like the lit fuse on a firecracker, it doesn't go out as it travels down the axon. It's this all-or-nothing quality that explains why your brain perceives an injury to a distant part of your body, like your toe, as painful as one to your nose. As mentioned earlier, when the action potential reaches the final button, the synaptic vesicles release their neurotransmitters into the synapse. Neurotransmitters cross the synapse and bind to receptors on the dendrites of the neighboring neuron, and the process repeats on the new neuron (as long as the signal is strong enough to trigger an action potential). Once the signal is delivered, excess neurotransmitters at the synapse move away, are broken down into inactive fragments, or are reabsorbed in a process known as reuptake. After reuptake, the neurotransmitter is pumped back into the neuron that released it to clear the synapse (Figure 3.12). Synapse clearing serves to provide a clear "on" and "off" state between signals and to regulate neurotransmitter production (complete synaptic vesicles provide signals that no additional neurotransmitters need be produced).

Figure 3.12 In reuptake, a neurotransmitter is transported from the synapse back to the axon terminal from which it was released.

Neural communication is often referred to as an electrochemical event. Movement of the action potential along the length of the axon is an electrical event, and movement of the neurotransmitter across the synaptic space represents the chemical part of the process.

LINK TO LEARN Click on this interactive simulation ( to take a closer look at neural communication.

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NEUROTRANSMITTERS AND PHARMACEUTICALS There are different types of neurotransmitters that are released by different neurons, and generally we can talk about the types of functions associated with different neurotransmitters (Table 3.1). Much of what psychologists know about the functions of neurotransmitters comes from research on the effects of medication on mental disorders. Psychologists who take a biological perspective and focus on the physiological causes of behavior argue that mental disorders such as depression and schizophrenia are associated with imbalances in one or more neurotransmitter systems. From this perspective, psychiatric medications can help to improve the symptoms associated with these disorders. Psychiatric drugs are medications that treat psychiatric symptoms by restoring the balance of neurotransmitters. Important neurotransmitters and how they influence behavior


Engaged in

Possible behavioral implications


muscle action, memory

Increased arousal, improved cognition


pain, joy

Less fear, less tension


mood, sleep, learning

Increased pleasure, suppressed appetite

Gamma-aminobutyric acid (GABA)

brain function, sleep

Less fear, less tension


memory, learn

Greater learning, better memory


Heart, gut, vigilance

Increased arousal, suppressed appetite


humor, I am

Modulated mood, suppressed appetite

Table 3.1

Psychoactive drugs can act as agonists or antagonists of a particular neurotransmitter system. Agonists are chemicals that mimic a neurotransmitter at the receptor site, enhancing its effects. An antagonist, on the other hand, blocks or interferes with the normal activity of a neurotransmitter at the receptor. Agonists and antagonists are prescribed to correct the specific neurotransmitter imbalances underlying a person's condition. For example, Parkinson's disease, a progressive disorder of the nervous system, is associated with low levels of dopamine. Therefore, dopamine agonists, which mimic the effects of dopamine by binding to dopamine receptors, are a treatment strategy. Certain symptoms of schizophrenia are associated with overactive dopamine neurotransmission. The antipsychotic medications used to treat these symptoms are dopamine antagonists - they block the effects of dopamine by binding to its receptors without activating them. In this way, they prevent the dopamine released by one neuron from transmitting information to neighboring neurons. Unlike agonists and antagonists, which work by binding to receptor sites, reuptake inhibitors prevent unused neurotransmitters from being transported back into the neuron. As a result, more neurotransmitters remain in the synapse longer, increasing its effectiveness. Depression, which is consistently associated with reduced serotonin levels, is usually treated with selective serotonin reuptake.


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Inhibitors (SSRIs). By preventing reuptake, SSRIs enhance the effects of serotonin, giving it more time to interact with serotonin receptors on dendrites. Common SSRIs on the market today are Prozac, Paxil and Zoloft. The drug LSD is structurally very similar to serotonin and acts on the same neurons and receptors as serotonin. Psychiatric drugs are not instant solutions for people with mental disorders. Often, a person must take a medication for several weeks before improvement occurs, and many psychoactive medications have significant negative side effects. Furthermore, individuals vary dramatically in how they respond to drugs. To increase the chances of success, it is not uncommon for people receiving pharmacotherapy to also undergo psychological and/or behavioral therapies. Some research suggests that combining drug therapy with other therapies tends to be more effective than treatment alone (eg, see March et al., 2007).

3.3 Components of the nervous system Learning objectives At the end of this section you will be able to: • describe the difference between the central and peripheral nervous system • explain the difference between the somatic and autonomic nervous system • distinguish between the sympathetic and parasympathetic nervous system Departments of the autonomic nervous system The nervous system can be divided into two main subdepartments: the central nervous system (CNS) and the peripheral nervous system (PNS), shown in Figure 3.13. The CNS consists of the brain and spinal cord; the PNS connects the CNS to the rest of the body. In this section, we focus on the peripheral nervous system; later we will see the brain and spinal cord.

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Figure 3.13 The nervous system is divided into two main parts: (a) the central nervous system and (b) the peripheral nervous system.

PERIPHERAL NERVOUS SYSTEM The peripheral nervous system is made up of thick bundles of axons called nerves, which carry messages between the CNS and the muscles, organs, and senses at the periphery of the body (that is, everything outside the CNS). The PNS has two main divisions: the somatic nervous system and the autonomic nervous system. The somatic nervous system is involved in activities traditionally considered conscious or voluntary. Is involved in transmitting sensory and motor information to and from the CNS; Therefore, it consists of motor neurons and sensory neurons. Motor neurons, which carry instructions from the CNS to muscles, are efferent fibers (efferent means "to move away"). The sensory neurons that carry sensory information to the CNS are afferent fibers (afferent means "moving towards"). Each nerve is basically a two-way highway containing thousands of axons, both efferent and afferent. The autonomic nervous system controls our internal organs and glands and is generally considered outside the realm of voluntary control. It can be further divided into sympathetic and parasympathetic (Fig. 3.14). The sympathetic nervous system is involved in preparing the body for stress-related activities; The parasympathetic nervous system is associated with returning the body to routine, day-to-day operations. The two systems have complementary functions and work together to maintain homeostasis in the body. Homeostasis is a state of equilibrium in which biological conditions (such as body temperature) are maintained at optimal levels.


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Figure 3.14 The sympathetic and parasympathetic portions of the autonomic nervous system have opposite effects on different systems.

The sympathetic nervous system is activated when we are faced with stressful or highly exciting situations. The activity of this system was adaptive for our ancestors and increased their chances of survival. For example, imagine that one of our first ancestors suddenly disturbed a large bear with its cubs while hunting small animals. At that moment, your body undergoes a series of changes—a direct function of sympathetic activation—that prepare you to face the threat. Your pupils dilate, your heart rate and blood pressure increase, your bladder relaxes, your liver releases glucose, and adrenaline rises in your bloodstream. Known as the fight-or-flight response, this constellation of physiological changes allows the body to tap into energy stores and heighten sensory capacity to ward off a threat or flee to safety.

LINK TO LEARN Reinforce what you've learned about the nervous system by playing this interactive game produced by the BBC ( about the nervous system.

While it's clear that such a response would have been vital for our ancestors who lived in a world filled with real physical threats, many of the highly hectic situations we face in the modern world are more psychological in nature. For example, think about how you feel when you have to get up and give a presentation in front of a room full of people or just before taking a big test. You are not in real physical danger in these situations, but you have evolved to respond to any perceived threat with the fight-or-flight response. This kind of response is not as adaptable in the modern world; in fact we suffer

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negative health consequences when we are constantly confronted with psychological threats that we can neither fight nor escape. Recent research suggests that increased susceptibility to heart disease (Chandola, Brunner & Marmot, 2006) and impaired immune system function (Glaser & Kiecolt-Glaser, 2005) are among the many negative consequences of prolonged and repeated exposure to stressful. Once the threat is eliminated, the parasympathetic nervous system takes over, returning the body's functions to a relaxed state. Our Hunter's heart rate and blood pressure return to normal, his pupils constrict, he regains control of his bladder, and his liver begins storing glucose in the form of glycogen for future use. These processes are associated with activation of the parasympathetic nervous system.

3.4 The Brain and Spinal Cord Learning Objectives By the end of this section, you will be able to: • explain the functions of the spinal cord • identify the hemispheres and lobes of the brain • describe the types of techniques available to clinicians and researchers. or scan the brain The brain is a remarkably complex organ composed of billions of interconnected neurons and glial cells. It is a bilateral or two-sided structure that can be divided into different lobes. Each lobe is associated with specific types of functions, but ultimately all areas of the brain interact with each other to form the basis of our thoughts and behavior. In this section, we discuss the general organization of the brain and the functions associated with different areas of the brain, starting with what can be seen as an extension of the brain, the spinal cord.

THE SPINAL CORD The spinal cord can be said to connect the brain with the outside world. This allows the brain to act. The spinal cord is like a relay station, but a very smart one. Not only does it transmit messages to and from the brain, it also has its own system of automatic processes called reflexes. The tip of the spinal cord merges with the brainstem, where basic life processes such as breathing and digestion are controlled. In the opposite direction, the spinal cord ends just below the ribs -- contrary to what we might expect, it doesn't reach the end of the spine. The spinal cord is functionally divided into 30 segments that correspond to the vertebrae. Each segment is connected to a specific part of the body through the peripheral nervous system. Spinal nerves branch out at each vertebra. Sensory nerves carry messages; motor nerves send messages to muscles and organs. Messages travel to and from the brain through each segment. Some sensory messages are processed immediately by the spinal cord, with no input from the brain. Heat starvation and reflex are two examples. When a sensory message meets certain parameters, the spinal cord triggers an automatic reflex. The signal travels from the sensory nerve to a simple processing center that triggers a motor command. Seconds are saved because messages don't have to go to the brain, be processed and sent back. When it comes to survival, spinal reflexes allow the body to react extraordinarily quickly. The spinal cord is protected by bony vertebrae and padded with cerebrospinal fluid, but injuries still occur. If the spinal cord is damaged in a specific segment, all the lower segments will be severed from the brain, resulting in paralysis. The less damage to the spine, the less function an injured person loses.


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THE TWO HEMISPHERES The surface of the brain, known as the cerebral cortex, is very uneven, characterized by a characteristic pattern of folds or ridges known as gyri (singular: gyrus) and furrows, known as sulci (singular: sulcus), shown in Figure 3.15 . These gyri and sulci form important landmarks that allow us to divide the brain into functional centers. The most prominent groove, known as the longitudinal fissure, is the deep groove that separates the brain into two halves, or hemispheres: the left hemisphere and the right hemisphere.

Fig. 3.15 The surface of the brain is covered by gyri and sulci. A deep groove is called a fissure, like B. the longitudinal cleft that divides the brain into left and right hemispheres. (Credit: Modification of the work by Bruce Blaus)

There is evidence of some specialization of function – called lateralization – in each hemisphere, mainly related to differences in language ability. Beyond that, however, the differences found are small. What we do know is that the left hemisphere controls the right side of the body and the right hemisphere controls the left side of the body. The two hemispheres are connected by a thick band of nerve fibers known as the corpus callosum, made up of about 200 million axons. The corpus callosum allows the two hemispheres to communicate and allows information processed in one side of the brain to be shared with the other side. We are generally not aware of the different roles our two hemispheres play in day-to-day functions, but there are people who know very well the capabilities and functions of their two hemispheres. In some cases of severe epilepsy, doctors choose to cut the corpus callosum to control the spread of seizures (Figure 3.16). While this is an effective treatment option, it results in individuals with split brains. After surgery, these split-brain patients exhibit a variety of interesting behaviors. For example, a split-brain patient is unable to name an image displayed in the patient's left visual field because the information is available only in the right hemisphere, largely non-verbally. However, they manage to recreate the image with their left hand, which is also controlled by the right hemisphere. When the more verbal left hemisphere sees the hand-drawn image, the patient can name it (as long as the left hemisphere can interpret what was drawn with the left hand).

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Figure 3.16 (a,b) The corpus callosum connects the left and right cerebral hemispheres. (c) A scientist opens this dissected sheep brain to show the corpus callosum between the hemispheres. (Credit c: Modification of work by Aaron Bornstein)

LINK TO LEARN This interactive animation ( on the Nobel Prize website takes users through the hemispheres of the brain.

Much of what we know about the functions of different areas of the brain comes from studying changes in the behavior and abilities of people who have suffered brain damage. For example, researchers study behavioral changes caused by strokes to learn more about the functions of specific brain areas. A stroke, caused by an interruption in blood flow to a region of the brain, causes a loss of brain function in the affected region. The damage can be in a small area, and when it is, it gives researchers the ability to tie any resulting behavioral changes to a specific area. The types of deficits that occur after a stroke depend largely on where the damage occurred in the brain. Consider Theona, a smart, self-reliant 62-year-old woman. She recently suffered a stroke in the front part of her right hemisphere. This makes it very difficult for her to move her left leg. (As you learned earlier, the right hemisphere controls the left side of the body, and the brain's major motor centers are at the front of the head, in the frontal lobe.) Theona also underwent behavioral changes. For example, in the produce aisle at the supermarket, she sometimes eats grapes, strawberries and apples straight from their cartons before paying for them. This behavior - which would have embarrassed her before her stroke - is consistent with damage to another region of the frontal lobe - the prefrontal cortex, which is associated with judgment, reasoning and impulse control.

FOREBRAIN STRUCTURES The two hemispheres of the cerebral cortex form part of the forebrain (Figure 3.17), the largest part of the brain. The forebrain contains the cerebral cortex and several other structures that lie below the cerebral cortex (referred to as subcortical structures): the thalamus, hypothalamus, pituitary gland, and limbic system (collection of structures). The cerebral cortex, the outer surface of the brain, is associated with higher-level processes such as consciousness, thought, emotion, reasoning, language, and memory. Each cerebral hemisphere can be divided into four lobes, each with a different function.


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Figure 3.17 The brain and its parts can be divided into three main categories: forebrain, midbrain, and hindbrain.

Cerebral Lobes The four cerebral lobes are frontal, parietal, temporal, and occipital (Figure 3.18). The frontal lobe is located at the front of the brain and extends into a fissure known as the central sulcus. The frontal lobe is involved in reasoning, motor control, emotions and language. It contains the motor cortex involved in planning and coordinating movements; the prefrontal cortex, responsible for high-level cognitive functions; and Broca's area, essential for language production.

Figure 3.18 The cerebral lobes are shown.

People who suffer damage to Broca's area have great difficulty producing any form of language (Figure 3.18). For example, Padma was a socially active electrical engineer and a caring and devoted mother. About twenty years ago, she was in a car accident and sustained damage in the Broca area. She completely lost the ability to speak and form meaningful language. Her mouth or vocal cords are fine, but she cannot pronounce words. She can follow instructions but cannot respond verbally, and she can read but no longer write. She can perform routine tasks, such as going to the market to buy milk, but she cannot communicate verbally when the situation calls for it. Perhaps the most famous case of frontal lobe damage is that of a man named Phineas Gage. On September 13, 1848, Gage (25 years old) was working as a railroad foreman in Vermont. He and his team used an iron rod to place explosives in a blast hole to clear the rocks along the railroad track. Unfortunately, the iron rod created a spark and detonated the rod out of the blast hole, into Gage's face and through his skull (Figure 3.19). Despite lying in a pool of his own blood and brain matter pouring out of his head, Gage was conscious and able to stand, walk and talk. but in the months

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After the accident, people noticed that his personality had changed. Many of his friends described him as not being himself anymore. Before the accident, Gage was considered a mild-mannered man with a soft voice, but after the accident he behaved strangely and inappropriately. Such personality changes would coincide with the loss of impulse control - a function of the frontal lobe. In addition to damage to the frontal lobe itself, later studies of the rod pathway have also identified possible damage to pathways between the frontal lobe and other brain structures, including the limbic system. As the connections between the planning functions of the frontal lobe and the emotional processes of the limbic system were severed, Gage had difficulty controlling his emotional impulses. However, there is evidence that the dramatic changes in Gage's personality were exaggerated and embellished. Gage's case emerged in the midst of a 19th-century debate over localization — whether certain areas of the brain are linked to certain functions. Based on extremely limited information about Gage, the extent of his injury, and his life before and after the accident, scholars tend to find support for their own views, whichever side of the debate they take (Macmillan, 1999) .

Figure 3.19 (a) Phineas Gage holds the iron rod that entered his skull in a railroad construction accident in 1848. (b) Gage's prefrontal cortex was severely damaged in the left hemisphere. The wand entered Gage's face from the left side, passed behind his eye and exited through the top of his skull before landing about 25 meters away. (Credit to: Modification of work by Jack and Beverly Wilgus)

The brain's parietal lobe is located just behind the frontal lobe and is involved in processing information from the body's senses. It contains the somatosensory cortex, which is essential for processing sensory information from throughout the body, such as touch, temperature, and pain. The somatosensory cortex is topographically organized, which means that the spatial relationships that exist in the body are maintained on the surface of the somatosensory cortex (Figure 3.20). For example, the part of the cortex that processes sensory information from the hand is adjacent to the part that processes information from the wrist.


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Fig. 3.20 The spatial relationships in the body are reflected in the organization of the somatosensory cortex.

Located on the side of the head (temporal meaning "near the temples"), the temporal lobe is associated with hearing, memory, emotions, and some aspects of language. The auditory cortex, the main area responsible for processing auditory information, is located in the temporal lobe. Wernicke's area, important for understanding speech, is also located here. Whereas individuals with damage to Broca's area have difficulty producing speech, individuals with damage to Wernicke's area can produce reasonable speech but are unable to understand it (Figure 3.21).

Fig. 3.21 Lesions in Broca's area or Wernicke's area can lead to speech deficits. However, the types of deficits vary greatly depending on which area is affected.

Located at the very back of the brain, the occipital lobe contains the primary visual cortex, which is responsible for interpreting incoming visual information. The occipital cortex is retinotopically organized, which means that there is a close relationship between the position of an object in a person's visual field and the position of the representation of that object in the cortex. You will learn much more about how visual information is processed in the occipital lobe by studying sensation and perception.

Other Areas of the Forebrain Other areas of the forebrain, located below the cerebral cortex, include the thalamus and the limbic system. The thalamus is a sensory relay for the brain. All of our senses, except smell, are

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through the thalamus before being sent to other areas of the brain for processing (Figure 3.22).

Figure 3.22 The thalamus serves as the brain's relay center, where most of the senses are directed for processing.

The limbic system is involved in processing emotions and memories. Interestingly, the sense of smell projects directly into the limbic system; Not surprisingly, smells can evoke emotional responses in ways that other sensory modalities cannot. The limbic system is made up of several different structures, but three of the most important are the hippocampus, amygdala, and hypothalamus (Figure 3.23). The hippocampus is an essential structure for learning and memory. The amygdala is involved in our experience of emotions and in associating emotional meaning with our memories. The hypothalamus regulates a number of homeostatic processes, including the regulation of body temperature, appetite and blood pressure. The hypothalamus also serves as an interface between the nervous and endocrine systems and in the regulation of sexual motivation and behavior.

Figure 3.23 The limbic system is involved in mediating emotional response and memory.

The Case of Henry Molaison (H.M.) In 1953, Henry Gustav Molaison (H.M.) was a 27-year-old man suffering from severe seizures. In an attempt to control his seizures, HM underwent brain surgery to remove his hippocampus and amygdala. After the operation, H.M. became much less severe, but he also suffered from some


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Unexpected - and devastating - consequences of the operation: he lost the ability to form many types of new memories. For example, he failed to learn new facts, such as who the President of the United States was. He was able to learn new skills, but then he didn't remember to learn them. For example, although he could learn to use a computer, he would have no conscious memory of having used one. He couldn't remember new faces and he couldn't remember events even immediately after they happened. Researchers were intrigued by his experience, and he is considered one of the best-studied cases in medical and psychological history (Hardt, Einarsson, & Nader, 2010; Squire, 2009). In fact, his case provided a great deal of insight into the role the hippocampus plays in consolidating new learning into explicit memory.

LINK TO LEARN Clive Wearing, an accomplished musician, lost the ability to form new memories when his hippocampus was damaged by illness. Watch the first few minutes of this video documentary ( for an introduction to this man and his condition.

Midbrain and Midbrain Structures The midbrain consists of structures located deep in the brain, between the forebrain and hindbrain. The reticular formation is centered in the midbrain, but actually extends into the forebrain and down into the hindbrain. The reticular formation is important in regulating the sleep-wake cycle, arousal, alertness and motor activity. Also in the midbrain are the substantia nigra (lat. “substantia nigra”) and the ventral tegmental area (VTA) (Fig. 3.24). Both regions contain cell bodies that produce the neurotransmitter dopamine, and both are essential for movement. Degeneration of the substantia nigra and VTA is implicated in Parkinson's disease. Furthermore, these structures are involved in mood, reward, and addiction (Berridge & Robinson, 1998; Gardner, 2011; George, Le Moal, & Koob, 2012).

Fig. 3.24 The substantia nigra and the ventral tegmental area (VTA) are located in the midbrain.

The hindbrain is located at the back of the head and looks like an extension of the spinal cord. It contains the medulla, pons and cerebellum (Fig. 3.25). The medulla controls the automatic processes of the autonomic nervous system, such as breathing, blood pressure, and heart rate. The word pons literally

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means "bridge" and, as the name suggests, the bridge serves to connect the brain and spinal cord. It is also involved in regulating brain activity during sleep. The medulla, pons, and midbrain together are called the brainstem.

Figure 3.25 The pons, medulla, and cerebellum form the hindbrain.

The cerebellum (Latin for "little brain") receives signals from muscles, tendons, joints and structures in our ears to control balance, coordination, movement and motor skills. The cerebellum is also believed to be an important area for processing some types of memories. In particular, procedural memory, or the memory involved in learning and remembering to perform tasks, is thought to be associated with the cerebellum. Remember that H.M. it could not form new explicit memories, but it could learn new tasks. Probably because the cerebellum of H.M. remained intact.

WHAT DO YOU THINK? Brain dead and alive What would you do if your spouse or loved one was declared brain dead but their body was being kept alive by medical devices? Whose decision should it be to remove a feeding tube? Should the cost of medical care be a factor? On February 25, 1990, a Florida woman named Terri Schiavo went into cardiac arrest, apparently triggered by an episode of bulimia. She was eventually revived, but her brain had been deprived of oxygen for a long time. Brain scans showed that there was no activity in her cerebral cortex and she suffered from severe and permanent brain atrophy. Basically, Schiavo was in a vegetative state. Medical professionals determined that she would never again be able to move, speak or react in any way. She needed a feeding tube to stay alive and there was no chance her situation would improve. From time to time Schiavo's eyes moved and sometimes she moaned. Despite the doctors' claims to the contrary, her parents believed these were signs that she was trying to communicate with them. After 12 years, Schiavo's husband argued that his wife did not want to be kept alive without feelings, sensations or brain activity. However, her parents were very opposed to the removal of her feeding tube. Eventually, the case made its way to the courts, both at the state of Florida and at the federal level. In 2005, the courts ruled in favor of Schiavo's husband, and the feeding tube was removed on March 18, 2005. Schiavo died 13 days later. Why did Schiavo's eyes sometimes move and why did she moan? Although the parts of her brain that


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Controlling thoughts, voluntary movements and feelings were completely damaged, his brainstem was still intact. His marrow and pons held his breath, causing involuntary eye movements and occasional moans. In the 15 years that she received a feeding tube, Schiavo's medical expenses may have exceeded $7 million (Arnst, 2003). These issues were brought to the public's attention 25 years ago in the case of Terri Schiavo, and remain so today. In 2013, a 13-year-old girl who suffered complications after tonsillectomy was declared brain dead. There was a battle between her family, who wanted her to be kept alive, and the hospital's policy on people who are declared brain dead. In another complicated case from 2013-14 in Texas, a pregnant paramedic who had been declared brain dead was kept alive for weeks despite her wife's instructions, based on her wishes, should such a situation arise. In that case, state laws kicked in to protect the fetus until doctors determined the fetus was nonviable. Decisions about the medical response to patients who have been declared brain dead are complex. What do you think about these issues?

BRAIN IMAGING You learned how brain injuries can provide information about the functions of different parts of the brain. Increasingly, however, we are able to obtain this information through brain imaging of people who have not suffered brain damage. In this section, we take a deeper look at some of the techniques available for brain imaging, including techniques that rely on radiation, magnetic fields, or electrical activity in the brain.

Radiation techniques Computed tomography (CT) takes multiple x-rays of a specific section of a person's body or brain (Figure 3.26). X-rays pass through tissues of different densities at different speeds, allowing a computer to create a general image of the area of ​​the body being scanned. A CT scan is often used to determine if someone has a tumor or significant brain atrophy.

Fig. 3.26 A CT scan can be used to visualize brain tumors. (a) The left image shows a healthy brain, while (b) the right image shows a brain tumor in the left frontal lobe. (Credit a: Modification of work by "Aceofhearts1968"/Wikimedia Commons; Credit b: Modification of work by Roland Schmitt et al.)

Positron emission tomography (PET) scans produce images of the active, living brain (Figure 3.27). A person who receives a PET scan drinks or is injected with a slightly radioactive substance called a tracer. Once in the bloodstream, the amount of tracer in a specific region of the brain can be monitored. As areas of the brain become more active, more blood flows to that area. A computer monitors the tracker's movement and creates a rough map of the brain's active and inactive areas during a specific behavior. PET scans show little detail, are unable to pinpoint events in time, and require the brain to be uncovered

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to radiation; Therefore, this technique has been replaced by fMRI as an alternative diagnostic tool. However, in certain contexts, PET technology is still used in combination with CT. For example, CT/PET scans allow for better representation of neurotransmitter receptor activity and open new avenues in schizophrenia research. This CT/PET hybrid technology, CT provides clear images of brain structures, while PET shows brain activity.

Figure 3.27 A PET scan is useful for showing activity in different parts of the brain. (Image credit: Department of Health and Human Services, National Institutes of Health)

Techniques using magnetic fields In magnetic resonance imaging (MRI), a person is placed in a machine that generates a strong magnetic field. The magnetic field sets the hydrogen atoms in the body's cells in motion. When the magnetic field is turned off, the hydrogen atoms emit electromagnetic signals as they return to their original position. Fabrics of different densities emit different signals, which a computer interprets and displays on a monitor. Functional magnetic resonance imaging (fMRI) works on the same principles but shows changes in brain activity over time by tracking blood flow and oxygen levels. fMRI provides more detailed images of brain structure and better temporal accuracy than PET scans (Figure 3.28). Due to their high level of detail, MRI and fMRI are commonly used to compare the brains of healthy individuals with the brains of individuals diagnosed with mental disorders. This comparison helps determine what structural and functional differences exist between these populations.

Figure 3.28 An fMRI shows brain activity over time. This image represents a single frame from an fMRI. (Credit: Modification of work by Kim J, Matthews NL, Park S.)


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LINK TO LEARN Visit this virtual lab ( to learn more about MRI and fMRI.

Techniques Involving Electrical Activity In some situations, it is useful to gain an understanding of the general activity of a person's brain without needing information about the actual location of the activity. Electroencephalography (EEG) serves this purpose by providing a measure of the brain's electrical activity. An array of electrodes is placed around the subject's head (Figure 3.29). Signals received by the electrodes result in a printout of your brain's electrical activity or brain waves, showing both the frequency (number of waves per second) and the amplitude (height) of the brain waves recorded with millisecond precision. This information is especially useful for researchers studying sleep patterns in people with insomnia.

Figure 3.29 Using electrode caps, modern EEG research can study the precise timing of all brain activity. (Image credit: SMI Eyetracking)

3.5 The Endocrine System Learning Objectives By the end of this section you will be able to: • identify the major glands of the endocrine system • identify the hormones secreted by each gland • describe the role of each hormone in regulating bodily functions producing chemicals known as hormones (Figure 3.30). Like neurotransmitters, hormones are chemical messengers that must bind to a receptor to send their signal. However, unlike neurotransmitters, which are released in close proximity to cells with their receptors, hormones are released into the bloodstream and travel throughout the body, affecting every cell that contains receptors for them. Thus, whereas the effects of neurotransmitters are localized, the effects of hormones are generalized. In addition, hormones act more slowly and tend to last longer.

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Figure 3.30 The major glands of the endocrine system are shown.

Hormones are involved in regulating all kinds of bodily functions and are ultimately controlled by interactions between the hypothalamus (in the central nervous system) and the pituitary gland (in the endocrine system). Hormonal imbalances are linked to a number of medical conditions. This section examines some of the major glands that make up the endocrine system and the hormones secreted by these glands.

MAJOR GLANDS The pituitary gland arises from and works closely with the hypothalamus at the base of the brain. The pituitary gland is often called the "master gland" because its messenger hormones control all the other glands in the endocrine system, although it primarily executes the instructions of the hypothalamus. In addition to messenger hormones, the pituitary gland also secretes growth hormone, pain-relieving endorphins, and several important hormones that help regulate fluid levels in the body. The thyroid is located in the neck and secretes hormones that regulate growth, metabolism and appetite. In hyperthyroidism or Graves' disease, the thyroid gland secretes too much of the hormone thyroxine, causing restlessness, bulging eyes, and weight loss. In the case of hypothyroidism, a reduced hormone level makes those affected feel tired and often complain of cold. Fortunately, thyroid disorders are usually treatable with medications that help restore the balance of hormones secreted by the thyroid. The adrenal glands sit on top of our kidneys and secrete hormones involved in the stress response, such as epinephrine (adrenaline) and norepinephrine (noradrenaline). The pancreas is an internal organ that secretes hormones that regulate blood sugar levels: insulin and glucagon. These pancreatic hormones are essential for maintaining stable blood sugar levels throughout the day by lowering (insulin) or raising (glucagon) blood sugar levels. People with diabetes do not produce enough insulin; As a result, they must take medications that stimulate or replace insulin production and must strictly control the amount of sugar and carbohydrates they eat. The gonads secrete sex hormones important for reproduction and mediate both sexual motivation and behavior. The female gonads are the ovaries; the male gonads are the testes. ovaries


Chapter 3 | biopsychology

testicles secrete estrogens and progesterone, and the testes secrete androgens such as testosterone.

DIG DEEPER Athletes and Anabolic Steroids Although it violates federal law and many professional sports organizations (such as the National Football League) have banned its use, anabolic steroids continue to be used by amateur and professional athletes alike. The drugs are believed to enhance athletic performance. Anabolic steroid drugs mimic the action of the body's own steroid hormones, such as testosterone and its derivatives. These drugs have the potential to provide a competitive advantage by increasing muscle mass, strength and endurance, although not all users may experience these results. Also, taking performance-enhancing drugs (PEDs) has its risks. Anabolic steroid use has been linked to a wide variety of potentially negative consequences, ranging in severity from largely cosmetic (acne) to life-threatening (heart attack). In addition, the use of these substances can cause profound mood swings and increase aggressive behavior (National Institute on Drug Abuse, 2001). Baseball player Alex Rodriguez (A-Rod) has been the focus of a media storm for his use of illegal PEDs. Rodriguez's on-field performance was unprecedented while on drugs; His success played a big part in negotiating a contract that made him the highest-paid player in professional baseball. Although Rodriguez claims not to have used PEDs for several years, he received a substantial suspension in 2013 that, if upheld, will cost him over $20 million in revenue (Gaines, 2013). What do you think about athletes and doping? Why or why should the use of PEDs be banned? What advice would you give an athlete who is considering using PEDs?

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Chapter 3 | biopsychology


Key Terms Action Potential The electrical signal that travels down the axon of the adrenal gland neuron sits in our kidneys and secretes hormones involved in the stress response. Agonist drug that mimics or enhances the effects of an all-or-nothing phenomenon of a neurotransmitter in which the input signal from another neuron is either sufficient or insufficient to reach the excitation threshold Allele-specific version of an amygdala gene structure in the system limbic involved in our experience of emotions and assigns emotional meaning to our memories band of cortex in the temporal lobe responsible for processing auditory information autonomic nervous system controls our internal organs and glands axon major extension of the soma biological vision with which mental disorders such as depression and schizophrenia are associated with imbalances in one or more neurotransmitter systems Broca's region in the left hemisphere essential for language production, central nervous system (CNS), brain and spinal cord, cerebellum, hindbrain structure that controls our balance, nodes that controls coordination, movement and our skills and is thought to be important in processing some species Memory Cerebral cortex Brain surface associated with our higher mental abilities Chromosome Long chain of genetic information Computed tomography (CT) - Scanning imaging technique in which a computer coordinates and integrates multiple X-rays of a specific area thick neural band fibers of the corpus callosum connecting the two hemispheres of the brain dendritic extension of the soma that receives input signals from other neurons helical molecule of deoxyribonucleic acid (DNA) made from nucleotide base pairs diabetic disease im Associated with insufficient insulin production Dominant allele Allele whose phenotype is expressed in an individual who has that allele Electroencephalography (EEG) Recording of electrical activity in the brain via electro the endocrine system in the scalp set of glands that produce chemicals known as hormones epigenetic study co of gene-environment interactions, eg. B. how the same genotype leads to different phenotypes


Chapter 3 | biopsychology

Fight-or-flight response Activation of the sympathetic portion of the autonomic nervous system, which allows access to energy stores and increased sensory capacity so that we can repel a given threat or safely flee Forebrain Largest part of the brain that contains the cerebral cortex, the thalamus and limbic system, including fraternal twins Twins who develop from two different eggs fertilized by different sperm, so their genetic material varies in the same way as in non-twin siblings Frontal lobe Part of the cerebral cortex involved in thought, control engine and emotion and language; contains functional magnetic resonance imaging (fMRI) images of the motor cortex MRI showing changes in metabolic activity over time Genetic DNA sequence that controls or partially controls physical traits Genetic environmental correlation View of gene-environment interaction that asserts that our genes shape our environment and our The environment affects the expression of our genes genotype genetic makeup of an individual glial nervous system cell that provides physical and metabolic support to neurons, including neuronal isolation and communication, and nutrient and waste transport gonads secretes sex hormones important for life successful reproduction and mediates both sexual processes motivation and behavior gyrus (plural: gyri) lump or ridge in cerebral cortex left or right cerebral hemisphere heterozygous consisting of two different alleles hindbrain division of brain with medulla, pons, and cerebellum structure in the temporal lobe of the h ipocampus associated with balanced state of learning and memory homeostasis – biological conditions such as body temperature are maintained at optimal levels homozygous composed of two identical alleles chemical messenger hormone of endocrine glands hypothalamus forebrain structure that regulates sexual motivation and behavior and a series of homeostatic processes; serves as an interface between the nervous system and the endocrine system identical twins twins who develop from the same concept of sperm and egg lateralization each hemisphere of the brain is associated with specialized functions limbic system collection of structures involved in processing emotions and memories are deep longitudinal tear grooves involved in magnetic resonance imaging (MRI) cerebral cortex magnetic fields, which are used to create an image of the photographed tissue

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hindbrain medulla structure that controls automated processes such as breathing, blood pressure, and heart rate membrane potential difference in charge across the neural membrane midbrain division of the brain, located between the forebrain and hindbrain; contains the reticular formation of the motor cortex band of cortex involved in planning and coordinating movement mutation sudden and permanent change in a gene fatty substance of the myelin sheath, the axons insulates neuronal cells in the nervous system, which act as interconnected information processors essential for all nervous system neurotransmitter chemical messenger tasks from the occipital lobe part of the cerebral cortex nervous system associated with visual processing; contains the primary visual cortex The pancreas secretes hormones that regulate blood sugar Parasympathetic nervous system associated with the routine, daily operations of the body Parietal lobe Part of the cerebral cortex involved in processing various sensory and perceptual information; contains the primary somatosensory cortex peripheral nervous system (PNS) connects the brain and spinal cord to the muscles, organs, and senses in the periphery of the body phenotype inherited physical traits of the individual pituitary gland secretes a number of key hormones that regulate fluid levels in the body and a set of messenger hormones that control the activity of other glands in the endocrine system; involved in regulating brain activity during positron emission tomography (PET) scans involves injecting people with a mildly radioactive substance and monitoring changes in blood flow to different regions of the prefrontal cortex in the frontal lobe, which is responsible for higher-level cognitive function from psychiatric drugs Drugs that treat psychiatric symptoms by restoring neurotransmitter balance The response area claims that our genes set the limits within which we can operate, and our environment interacts with the genes to determine where in this area we fall in the receptor protein on the cell surface to which neurotransmitters recessively attach allele allele whose phenotype is only expressed when an individual is homozygous for that allele. resting potential the waiting state of the membrane potential of a neuron between signals


Chapter 3 | biopsychology

reticular formation structure of the midbrain important in regulating the sleep-wake cycle, awakening, wakefulness and resumption of motor activity the neurotransmitter is pumped back into the neuron, which released a semipermeable membrane cell membrane that allows the passage of smaller molecules or molecules without an electrical charge , When larger or highly charged molecules are disrupted, the somatic cell body's somatic nervous system relays sensory and motor information to and from the somatosensory cortex of the CNS, which is essential for processing sensory information from throughout the body, such as touch , temperature and pain Substantia nigra structure of the midbrain, in which dopamine is produced; Involved in controlling movement Groove (plural: grooves) Depressions or furrows in the cerebral cortex Sympathetic nervous system Involved in stress-related activities and functions Synapse Small gap between two neurons where communication occurs Synaptic vesicles Storage site of neurotransmitters Temporal lobe Part of the cortex cerebral associated with hearing, memory, emotion and some aspects of language; contains terminal of primary auditory cortex axon terminal bud contains synaptic vesicles thalamus sensory relay to brain theory of evolution by natural selection postulates that organisms best suited to their environment survive and reproduce compared to those unsuited to their arousal threshold charge level in the membrane that causes the neuron to become active. The thyroid secretes hormones that regulate growth, metabolism and appetite.

Summary 3.1 Human Genetics Genes are DNA sequences that encode a specific trait. Different versions of a gene are called alleles - sometimes alleles can be classified as dominant or recessive. A dominant allele always leads to the dominant phenotype. To exhibit a recessive phenotype, an individual must be homozygous for the recessive allele. Genes affect physical and psychological characteristics. How and when a gene is expressed and what the result will be - both in terms of physical and psychological characteristics - is ultimately a function of the interaction between our genes and our environment.

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3.2 Cells of the Nervous System Glia and neurons are the two types of cells that make up the nervous system. Although glial cells generally play a supportive role, communication between neurons is critical to all functions associated with the nervous system. Neural communication is made possible by the specialized structures of the neuron. The soma contains the nucleus and the dendrites extend from the soma in tree-like branches. The axon is another important extension of the cell body; Axons are usually covered by a myelin sheath, which increases the speed at which nerve impulses are transmitted. At the end of the axon are terminal buds that contain synaptic vesicles filled with neurotransmitters. Neural communication is an electrochemical event. Dendrites contain receptors for neurotransmitters that are released by nearby neurons. When signals received from other neurons are strong enough, an action potential travels the length of the axon to the terminal buds, resulting in the release of neurotransmitters at the synapse. Action potentials function on an all-or-nothing basis and involve the movement of Na+ and K+ across the neuronal membrane. Different neurotransmitters are associated with different functions. Mental disorders often involve imbalances in a particular neurotransmitter system. Therefore, psychotropic drugs are prescribed to bring neurotransmitters back into balance. Drugs can act as both agonists and antagonists for a given neurotransmitter system. 3.3 Parts of the nervous system The brain and spinal cord form the central nervous system. The peripheral nervous system is composed of the somatic and autonomic nervous systems. The somatic nervous system transmits sensory and motor signals to and from the central nervous system. The autonomic nervous system controls the function of our organs and glands and can be divided into sympathetic and parasympathetic. Sympathetic activation prepares us for fight or flight, while parasympathetic activation is associated with normal functioning under conditions of relaxation. 3.4 The brain and spinal cord The brain consists of two hemispheres, each controlling opposite sides of the body. Each hemisphere can be divided into different lobes: frontal, parietal, temporal and occipital lobes. In addition to the lobes of the cerebral cortex, the forebrain includes the thalamus (sensory relays) and the limbic system (emotional and memory circuits). The midbrain contains the reticular formation, which is important for sleep and waking, as well as the substantia nigra and the ventral tegmental area. These structures are important for movement, reward, and addiction processes. The hindbrain contains the brainstem structures (medulla, ponseus, and midbrain) that control automatic functions such as breathing and blood pressure. The hindbrain also contains the cerebellum, which helps coordinate movement and certain types of memories. Brain-damaged individuals have been studied extensively for information about the role of different areas of the brain, and recent advances in technology allow us to piece together similar information through imaging of brain structure and function. These techniques include CT, PET, MRI, fMRI and EEG. 3.5 The Endocrine System The glands of the endocrine system secrete hormones to regulate normal bodily functions. The hypothalamus serves as an interface between the nervous and endocrine systems and controls pituitary gland secretions. The pituitary gland serves as the master gland and controls the secretions of all other glands. The thyroid secretes thyroxine, which is important for basic metabolic processes and growth; the adrenal glands secrete hormones involved in the stress response; the pancreas secretes hormones that regulate blood sugar levels; and the ovaries and testes produce sex hormones that regulate sexual motivation and behavior.


Chapter 3 | biopsychology

Knowledge review 1. A(n) ________ is a sudden and permanent change in a DNA sequence. one. allele b. chromosome c. epigenetics d. Mutation 2. ________ refers to a person's genetic makeup, while ________ refers to a person's physical characteristics. one. phenotype; genotype B. Genotype; phenotype c. DNA; gene D. Gene; DNA 3. ________ is the field of study that focuses on genes and their expression. one. social psychology b. Evolutionary Psychology c. epigenetics D. Behavioral neuroscience 4. Humans have ________ pairs of chromosomes. one. 15 BC 23 c. 46d. 78 5. The ________ receives input signals from other neurons. one. sum b. terminal keys c. myelin sheath D. Dendrites 6. A(n) ________ facilitates or mimics the activity of a particular neurotransmitter system. one. axon b. SSRI-c. d agonist Antagonist 7. Multiple sclerosis involves a collapse of the ________. one. sum b. myelin sheath c. synaptic vesicles d. dendrites

8. In an action potential, Na+ moves ________ the cell and K+ moves ________ the cell. one. B. ç. ie

Inside; outside outside inside inside; inside Outside; Outside

9. Our ability to move our legs as we walk through space is controlled by the _______ nervous system. one. autonomous b. somatic c. sympathetic D. Parasympathetic 10. When your ________ is activated, you will be relatively comfortable. one. somatic nervous system b. sympathetic nervous system c. parasympathetic nervous system d. Spinal cord 11. The central nervous system consists of ________. one. sympathetic and parasympathetic nervous system b. organs and glands c. somatic and autonomic nervous system d. Brain and spinal cord 12. Sympathetic activation is associated with ________. one. pupil dilation b. Glucose storage in the liver c. increased heart rate d. A and C 13. The ________ is a sensory relay station where all sensory information except smell is relayed before being sent to other areas of the brain for further processing. one. amygdala b. hippocampus c. hypothalamus D. thalamus

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14. Injuries to the ________ impair the ability to understand speech but leave the ability to produce words intact. one. amygdala b. Broca's area c. Wernicke area d. Occipital Lobe 15. A(n) ________ uses magnetic fields to create images of specific tissue. one. EEG b. MRI c. PET scan D. CT scan 16. Which of the following structures is not part of the forebrain? one. thalamus b. hippocampus c. tonsil d. black substance


17. The two main hormones secreted by the pancreas are: a. estrogen and progesterone b. norepinephrine and epinephrine c. thyroxine and oxytocin d. Glucagon and Insulin 18. The ________ secretes messenger hormones that control the function of the rest of the endocrine glands. one. ovary B. thyroid c. pituitary D. Pancreas 19. The ________ gland secretes epinephrine. one. adrenal gland b. thyroid c. pituitary D. Master 20. The ________ secretes hormones that regulate the body's fluid balance. one. adrenal gland B. pituitary c. D. thyroid testicles

Critical Thinking Issues 21. The theory of evolution by natural selection requires the variability of a given trait. Why is variability necessary and where does it come from? 22. Cocaine has two effects on synaptic transmission: it interferes with dopamine reuptake and causes more dopamine to be released into the synapse. Would cocaine be classified as an agonist or antagonist? Because? 23. Drugs such as lidocaine and novocaine act as Na+ channel blockers. In other words, they prevent sodium from moving across the nerve membrane. Why does this specific action make these local anesthetic drugs so effective? 24. What are the effects of impaired immune function as a result of chronic stress? 25. Examine Figure 3.14, which illustrates the effects of activating the sympathetic nervous system. How would all these things affect the fight-or-flight response? 26. Before the advent of modern imaging techniques, scientists and clinicians relied on autopsies of people who suffered brain injuries with consequent behavioral changes to determine how different areas of the brain were affected. What limitations are associated with this type of approach?


Chapter 3 | biopsychology

27. Which of the techniques discussed would you consider viable options for determining how activity in the reticular formation is related to sleep and wakefulness? Because? 28. Hormone secretion is often regulated by a negative feedback mechanism, meaning that once a hormone is secreted, it causes the hypothalamus and pituitary to stop producing the signals needed to release the hormone in the first place. place. Most oral contraceptives consist of small doses of estrogen and/or progesterone. Why should this be an effective means of birth control? 29. Chemical messengers are used in the nervous and endocrine systems. What properties do these two systems have in common? Which properties are different? Which one would be faster? What would lead to lasting changes?

Personal Application Questions 30. You share half your genetic makeup with each of your parents, but you are certainly very different from both of them. Spend a few minutes writing down the similarities and differences between you and your parents. How do you think your unique environment and experiences contributed to some of the differences you see? 31. Have you or anyone you know ever received any psychiatric medication? If so, what side effects have been associated with the treatment? 32. I hope you don't face real physical threats from potential predators on a daily basis. However, you probably have your fair share of stress. What situations are your most common sources of stress? What can you do to try to minimize the negative consequences of these specific stressors in your life? 33. You read about H.M.'s memory deficits. after removing the hippocampus and amygdala. Have you ever come across a character in a book, TV show or movie who suffered from memory deficits? How was this character similar to and different from H.M.? 34. Given the negative health consequences associated with the use of anabolic steroids, what considerations can be made in a person's decision to use them?

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Chapter 4 | sensation and perception


Chapter 4

sensation and perception

Figure 4.1 If you were standing in the middle of this street scene, you would receive and process a multitude of sensory inputs. (Credit: Modification of work by Cory Zanker)

Chapter Overview 4.1 Sensation versus Perception 4.2 Waves and Wavelengths 4.3 Vision 4.4 Hearing 4.5 The Other Senses 4.6 Form Principles of Perception

Introduction Imagine that you are standing on the corner of a city street. You might notice movement everywhere as cars and people go about their business, the sound of music from a street musician or a horn blaring in the distance, the smell of exhaust fumes or groceries being sold by a nearby vendor and much more of that hard pavement feeling underfoot. We rely on our sensory systems to provide important information about our surroundings. We use this information to successfully navigate and interact in our environment so that we can find food, seek shelter, maintain social relationships and avoid potentially dangerous situations. This chapter provides an overview of how sensory information is received and processed by the nervous system and how this affects our conscious perception of the world. We begin by learning the difference between sensation and perception. Next, we consider the physical properties of light and sound stimuli, along with an overview of the basic structure and function of the major sensory systems. The chapter ends with a discussion of a historically important theory of perception called gestalt.


Chapter 4 | sensation and perception

4.1 Sensation versus Perception Learning Outcomes At the end of this section you will be able to: • distinguish between sensation and perception • describe the concepts of absolute threshold and difference threshold • discuss the role that attention, motivation and sensory adaptation play in perception

SENSATION What does it mean to feel something? Sensory receptors are specialized neurons that respond to specific types of stimuli. When sensory information is picked up by a sensory receptor, a sensation has occurred. For example, light entering the eye causes chemical changes in the cells that line the back of the eye. These cells transmit messages in the form of action potentials (as you learned from studying biopsychology) to the central nervous system. The conversion of sensory stimulus energy into action potential is called transduction. You've probably known since elementary school that we have five senses: sight, sound (hearing), smell (smell), taste (taste), and touch (somatosensory). It turns out that this notion of five senses is an oversimplification. We also have sensory systems that provide information about balance (vestibular sense), body position and movement (proprioception and kinesthesia), pain (nociception), and temperature (thermoception). The sensitivity of a given sensory system to relevant stimuli can be expressed as an absolute threshold. The absolute threshold refers to the minimum amount of stimulus energy that must be present for the stimulus to be detected 50% of the time. Another way to think about this is to ask how dim a light can be or how quiet a sound can be and still be heard half the time. The sensitivity of our sensory receptors can be surprising. It is estimated that the most sensitive sensory cells at the back of the eye can detect a candle flame 30 miles away on a clear night (Okawa & Sampath, 2007). Under silent conditions, hair cells (the receptor cells of the inner ear) can sense a clock ticking 20 feet away (Galanter, 1962). It is also possible for us to receive messages presented below the threshold of consciousness - these are called subliminal messages. A stimulus reaches a physiological threshold when it is strong enough to excite sensory receptors and send nerve impulses to the brain: this is an absolute threshold. A message below this limit is called subliminal: we receive it, but we are not aware of it. There has been a lot of speculation over the years about the use of subliminal messages in advertisements, rock music and self-help audio programs. Research shows that people in laboratory settings can process and respond to information outside of their awareness. But that doesn't mean we obey these messages like zombies; in fact, hidden messages have little impact on behavior outside the laboratory (Art-Wilson & Zajonc, 1980; Rensink, 2004; Nelson, 2008; Radel, Sarrazin, Legrain, & Gobancé, 2009; Loersch, Durso, & Petty, 2013 ). Absolute thresholds are usually measured under incredibly controlled conditions in situations ideal for sensitivity. Sometimes we are more interested in how much difference in stimuli it takes to differentiate between them. This is called just perceptible difference (jnd) or difference threshold. In contrast to the absolute threshold, the difference threshold changes depending on the stimulus intensity. For example, imagine that you are in a very dark movie theater. When a viewer receives a text message on their cell phone that lights up their screen, many people are likely to notice the change in theater lighting. However, if the same thing happened during a basketball game in a brightly lit arena, few people would notice. Cell phone brightness does not change, but its ability to be detected as a change in lighting varies dramatically between the two contexts. Ernst Weber proposed this theory of changing the difference threshold in the 1830s, and it became known as Weber's law: the difference threshold is a constant fraction of the original stimulus, as

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Chapter 4 | sensation and perception


the example illustrates.

PERCEPTION Although our sensory receptors are constantly collecting information from the environment, it is how we interpret that information that affects our interaction with the world. Perception refers to how sensory information is organized, interpreted, and consciously experienced. Perception involves bottom-up and top-down processing. Bottom-up processing refers to the fact that perceptions are constructed from sensory information. How we interpret these sensations, on the other hand, is influenced by our available knowledge, experiences and thoughts. This is called top-down processing. One way to think about this concept is that sensation is a physical process, whereas perception is psychological. For example, if you walk into a kitchen and smell the aroma of cinnamon rolls being baked, the sensation is that the olfactory receptors detect the smell of cinnamon, but the perception might be, "Mmm, this smells like that bread that grandma did, when the family got together for the holidays." Although our perceptions are built from sensations, not all sensations lead to perceptions. In fact, we often fail to notice stimuli that remain relatively constant over time. This is known as sensory adaptation. Positions Imagine you walk into a classroom with an old analogue clock. Upon entering the room for the first time, you will hear the clock ticking; when you start chatting with classmates or hear the teacher greeting the class, you will hear that the tick is no longer true. The tick is no longer true. the clock is still ticking and this information is still affecting the sensory receptors in the auditory system. that you no longer perceive sound demonstrates sensory adaptation and shows that sensation and perception, although closely related, are different. There is another factor that influences sensation and perception: attention. Attention plays a significant role in determining what is perceived and what is perceived. Imagine you are at a party filled with music, conversation and laughter. You'll have an interesting conversation with a friend, blocking out all background noise. If someone were to interrupt you to ask what song just played, you probably wouldn't be able to answer that question.

LINK TO LEARN See for yourself how inadvertent blindness works by checking this selective attention test ( by Simons and Chabris (1999).

One of the most interesting demonstrations of how attention is important for our perception of the environment occurred in a famous study by Daniel Simons and Christopher Chabris (1999). In this study, participants watched a video of people dressed in black and white walking past basketballs. Participants were asked to count the number of times the team in white passed the ball. During the video, a person in a black gorilla costume walks between the two teams. You would think someone would notice the gorilla, right? Nearly half of the video's viewers didn't notice the gorilla, despite being clearly visible for nine seconds. Because the participants were so focused on how many times the white team passed the ball, they completely turned off other visual information. Inattentional blindness is called inadvertent blindness. In a similar experiment, researchers tested inadvertent blindness by asking participants to watch moving images on a computer screen. They were instructed to focus on white or black objects and ignore the other color. When a red cross appeared on the screen, about a third of the participants did not notice it (Figure 4.2) (Most, Simons, Scholl, & Chabris, 2000).


Chapter 4 | sensation and perception

Figure 4.2 Nearly a third of study participants did not notice a red cross on the screen because their attention was focused on black or white numbers. (Credit: Cory Zanker)

Motivation can also affect perception. Have you ever waited for a very important call, and while taking a shower, thought you heard the phone ring, only to realize it wasn't? In this case, you saw how the motivation to recognize a meaningful stimulus can alter our ability to distinguish between a real sensory stimulus and background noise. The ability to identify a stimulus when it is embedded in a disturbing background is called signal recognition theory. This could also explain why a mother is awakened by her baby's soft murmur but not by other noises that occur during sleep. Signal detection theory has practical applications, such as B. Increasing the accuracy of air traffic controllers. Air traffic controllers must be able to detect aircraft among the many blips that appear on the radar screen and follow these aircraft as they move across the sky. In fact, the original work of the researcher who developed signal detection theory focused on improving the air traffic controller's sensitivity to aircraft blips (Swets, 1964). Our perceptions can also be influenced by our beliefs, values, prejudices, expectations and life experiences. As you will see later in this chapter, individuals deprived of the experience of binocular vision at critical stages of development have difficulty perceiving depth (Fawcett, Wang, & Birch, 2005). The shared experiences of people within a given cultural context can have profound effects on perception. For example, Marshall Segall, Donald Campbell and Melville Herskovits (1963) published the results of a multinational study in which they showed that people from Western cultures were more prone to certain types of visual illusions than people from non-Western cultures, and vice versa. . versa. One such illusion that Westerners were most likely to experience was the Müller-Lyer illusion (Figure 4.3): the lines appear to be different lengths, but are actually the same length.

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Chapter 4 | sensation and perception


Figure 4.3 In the Müller-Lyer illusion, the lines appear to be different lengths even though they are identical. (a) The arrows at the ends of the lines can make the right line appear longer, even if the lines are the same length. (b) When applied to a three-dimensional image, the right line may appear longer again, even though both black lines are the same length.

These perceptual differences were consistent with differences in the types of environmental cues that people regularly experience in a given cultural context. For example, people in Western cultures have a perceptive background of buildings with straight lines, in what Segall's study called the carpenter's world (Segall et al., 1966). In contrast, people from certain non-Western cultures with an unbiased view, such as the Zulu of South Africa, whose villages are made up of round huts arranged in a circle, are less susceptible to this illusion (Segall et al., 1999). 🇧🇷 It is not just vision that is influenced by cultural factors. Indeed, research has shown that the ability to identify an odor and rate its pleasantness and intensity varies across cultures (Ayabe-Kanamura, Saito, Distel, Martínez-Gómez & Hudson, 1998). Children described as thrill seekers are more likely to show taste preferences for intensely sour flavors (Liem, Westerbeek, Wolterink, Kok & de Graaf, 2004), suggesting that fundamental aspects of personality may influence cognition. Furthermore, people who are positive about low-fat foods are more likely to rate foods labeled low-fat as being tastier than people who are less positive about these products (Aaron, Mela, and Evans , 1994).

4.2 Waves and wavelengths Learning objectives By the end of this section, you will be able to: • describe important physical properties of waveforms • show how the physical properties of light waves are related to perceptual experience • show how the physical properties of light waves Sound waves are related to perceived experience Both visual and auditory stimuli come in the form of upward waves. Although the two stimuli are very different in composition, the waveforms share similar properties that are particularly important for our visual and auditory perception. In this section, we describe the physical properties of waves and the associated perceptual experiences.

AMPLITUDE AND WAVELENGTH Two physical properties of a wave are amplitude and wavelength (Figure 4.4). The breadth of a


Chapter 4 | sensation and perception

Wave is the distance from the centerline to the highest point of the wave crest or the bottom of the valley. Wavelength refers to the length of a wave from one peak to the next.

Figure 4.4 The amplitude or height of a wave is measured from peak to trough. The wavelength is measured from peak to peak.

The wavelength is directly related to the frequency of a specific waveform. Frequency refers to the number of waves passing a specific point in a specific time period and is usually expressed in Hertz (Hz) or cycles per second. Longer wavelengths have lower frequencies and shorter wavelengths have higher frequencies (Figure 4.5).

Figure 4.5 This figure shows waves of different wavelengths/frequencies. In the figure above, the red wave has a long wavelength/short frequency. Wavelengths decrease and frequencies increase from top to bottom.

LIGHT WAVES The visible spectrum is the part of the larger electromagnetic spectrum that we can see. As Figure 4.6 shows, the electromagnetic spectrum encompasses all electromagnetic radiation found in our environment and includes gamma rays, X-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves. The visible spectrum in humans is associated with wavelengths ranging from 380 to 740 nm - a very small distance, as a nanometer (nm) is a billionth of a meter. Other species can detect other parts of the electromagnetic spectrum. For example, bees can see light in the ultraviolet range (Wakakuwa, Stavenga & Arikawa, 2007), and some snakes can see infrared radiation in addition to more traditional visual light signals (Chen, Deng, Brauth, Ding & Tang, 2012; Hartline, Kass & Loop, 1978).

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Chapter 4 | sensation and perception


Figure 4.6 Light visible to humans makes up only a small part of the electromagnetic spectrum.

In humans, the wavelength of light is linked to color perception (Figure 4.7). Within the visible spectrum, our experience is associated with red at longer wavelengths, green at intermediate wavelengths, and blue and violet at shorter wavelengths. (An easy way to remember this is the ROYGBIV mnemonic: red, orange, yellow, green, blue, indigo, violet.) The amplitude of light waves is tied to our experience of brightness or color intensity, with larger amplitudes appearing more shiny.

Figure 4.7 Different wavelengths of light are associated with our perception of different colors. (Image credit: Modification of work by Johannes Ahlmann)

SOUND WAVES Like light waves, the physical properties of sound waves are linked to many aspects of how we perceive sound. The frequency of a sound wave is related to our perception of the pitch of that sound. High-frequency sound waves are perceived as high-pitched tones, while low-frequency sound waves are perceived as low-pitched tones. The audible range of sound frequencies is between 20 and 20,000 Hz, with the highest sensitivity being for frequencies in the middle of this range. As in the visible spectrum, other species show differences in their audible ranges. For example, chickens have a very limited hearing range of 125-2000 Hz. Mice have an auditory range of 1000-91000 Hz, and the beluga whale's auditory range is between 1000-123000 Hz. Our domestic dogs and cats have audible ranges of around 70-45,000 Hz or 45-64,000 Hz (Strain, 2003). The intensity of a given sound is closely related to the amplitude of the sound wave. Higher amplitudes are associated with louder sounds. Loudness is measured in decibels (dB), a logarithmic unit of sound intensity. A typical conversation would correspond to 60 dB; a rock concert can reach 120 dB (Figure 4.8). A whisper five feet away or a rustle of leaves is at the lower end of our range of hearing; Noises like a window air conditioner, normal conversation, and even heavy traffic or a vacuum cleaner are all within tolerable limits. However, there is a possibility of hearing damage.


Chapter 4 | sensation and perception

about 80 dB to 130 dB: These are sounds from a food processor, electric lawnmower, heavy truck (25 feet away), subway train (20 feet away), live rock music, and jackhammer. The pain threshold is about 130 dB, a jet plane taking off or a gun firing at close range (Dunkle, 1982).

Figure 4.8 This figure illustrates the volume of common sounds. (Aircraft credit: artwork modified by Max Pfandl; "Crowd" credit: artwork modified by Christian Holmér; "Blender" credit: artwork modified by Jo Brodie; "Auto" credit: artwork modified by NRMA New Cars/ Flickr ; Credit "Reden": modification of work by Joi Ito; Credit "Blätter": modification of work by Aurelijus Valeiša)

Although wave amplitude is usually associated with volume, there is some interaction between frequency and amplitude in our perception of volume within the audible range. For example, a 10 Hz sound wave is inaudible regardless of the wave's amplitude. A 1000 Hz sound wave, on the other hand, would change dramatically in terms of perceived loudness as the wave's amplitude increases.

LINK TO LEARN Watch this short video ( that shows how frequency and amplitude interact in our perception of volume.

Sure, different musical instruments can play the same musical note at the same volume, but they still sound quite different. This is called timbre. Timbre refers to the purity of a sound and is affected by the complex interplay of frequency, amplitude and timing of sound waves.

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Chapter 4 | sensation and perception


4.3 Vision Learning Objectives By the end of this section, you will be able to: • describe the basic anatomy of the visual system • discuss how rods and cones contribute to different aspects of vision • describe how monocular and binocular cues are used in visual perception depth The visual system builds a mental representation of the world around us (Figure 4.9). This contributes to our ability to successfully navigate physical space and interact with meaningful people and objects around us. This section provides an overview of the basic anatomy and function of the visual system. In addition, we will explore our ability to perceive colors and depth.

Figure 4.9 Our eyes pick up sensory information that helps us make sense of the world around us. (Image credit “top left”: work modification by “rajkumar1220”/Flickr”; Image credit “top right”: work modification by Thomas Leuthard; Image credit “middle left”: work modification by Demietrich Baker; Image credit “middle right”: work modification by "kaybee07"/Flickr; credit "bottom left": work modification by "Isengardt"/Flickr; credit "bottom right": work modification by Willem Heerbaart)

ANATOMY OF THE VISUAL SYSTEM The eye is the main sensory organ involved in vision (Figure 4.10). Light waves are transmitted through the cornea and enter the eye through the pupil. The cornea is the clear covering over the eye. It serves as a barrier between the inner eye and the outer world and is involved in focusing light waves entering the eye. The pupil is the small opening in the eye through which light passes, and the size of the pupil can change as a function of light intensity and emotional arousal. When light levels are low, the pupil dilates or dilates to allow more light to enter the eye. When light levels are high, the pupil constricts or shrinks to reduce the amount of light entering the eye. The size of the pupil is controlled by muscles attached to the iris, the colored part of the eye.


Chapter 4 | sensation and perception

Figure 4.10 The anatomy of the eye is shown in this diagram.

After passing through the pupil, light passes through the lens, a curved, transparent structure that serves to create additional focus. The lens is attached to muscles that can change shape to help focus light reflected from near or far objects. In a person with normal vision, the lens focuses images perfectly onto a small depression at the back of the eye known as the fovea, which is part of the retina, the light-sensitive lining of the eye. The fovea contains densely packed specialized photoreceptor cells (Fig. 4.11). Known as cones, these photoreceptor cells are light-sensitive cells. Cones are specialized types of photoreceptors that work best in bright light. Cones are very sensitive to fine detail and offer tremendous spatial resolution. They are also directly involved in our ability to perceive colors. While cones are concentrated in the fovea, where images are normally focused, rods, another type of photoreceptor, are found in the rest of the retina. Rods are specialized photoreceptors that function well in low light, and although they lack the spatial resolution and color function of cones, they are involved in our vision in dimly lit environments, as well as our perception of movement at the periphery of our area of ​​focus. eyesight.

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Figure 4.11 The two types of photoreceptors are shown in this figure. The cones are colored green and the rods are colored blue.

We've all experienced the different sensitivity of rods and cones when moving from a brightly lit environment to a dimly lit environment. Imagine that you are watching a blockbuster movie on a clear summer day. Entering the dark theater from the brightly lit lobby, you'll find that you immediately have trouble seeing much. After a few minutes you start to get used to the darkness and can see the inside of the theater. In the bright environment, his vision was mainly dominated by cone activity. As you move into the dark environment, bat activity dominates, but there is a delay in transitioning between phases. If your rods don't convert light into nerve impulses as easily and efficiently as they should, you'll have trouble seeing in dim light, a condition known as night blindness. Rods and cones are connected (through various interneurons) to the retinal ganglion cells. The axons of retinal ganglion cells converge and exit through the fundus to form the optic nerve. The optic nerve carries visual information from the retina to the brain. There is a point in the visual field called the blind spot: even if light from a small object is focused on the blind spot, we cannot see it. We are not aware of our blind spots for two reasons: first, each eye receives a slightly different view of the visual field; therefore, the blind spots do not overlap. Second, our visual system fills the blind spot, so although we are unable to respond to visual information that appears in that part of the visual field, we also don't realize that information is missing. The optic nerve for each eye fuses just below the brain at a point called the optic chiasm. As shown in Figure 4.12, the optic chiasm is an X-shaped structure that lies just below the cerebral cortex at the front of the brain. At the site of the optic nerve crossing, information from the right visual field (from both eyes) is sent to the left side of the brain, and information from the left visual field is sent to the right side of the brain.


Chapter 4 | sensation and perception

Figure 4.12 This figure shows the optic disc at the front of the brain and the pathways to the occipital lobe at the back of the brain, where visual sensations are processed into meaningful perceptions.

Once in the brain, visual information is sent through a series of structures to the occipital lobe at the back of the brain for processing. Visual information can be processed in parallel paths that can be broadly described as the "which way" path and the "where/how" path. The “which path” is involved in object recognition and identification, while the “where/how path” has to do with position in space and interaction with a given visual stimulus (Milner & Goodale, 2008; Ungerleider & Haxby, 1994 ). 🇧🇷 For example, if you see a ball rolling down the street, the "which path" identifies the object and the "where/how path" identifies its location or movement in space.

COLOR AND DEPTH PERCEPTION We don't see the world in black and white; We also don't see it as two-dimensional (2-D) or flat (just height and width, no depth). Let's see how color vision works and how we perceive three dimensions (height, width and depth).

Color vision People with normal vision have three different types of cones that mediate color vision. Each of these cone types is maximally sensitive to a slightly different wavelength of light. According to the trichromatic theory of color vision, shown in Figure 4.13, all colors in the spectrum can be created by combining red, green, and blue. Each of the three types of cones is sensitive to one of the colors.

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Figure 4.13 This figure illustrates the different sensitivities to the three types of cones found in a person with normal vision. (Image credit: Modification of work by Vanessa Ezekowitz)

The trichromatic theory of color vision is not the only theory – another important theory of color vision is known as the counterprocess theory. According to this theory, the color is encoded in pairs of opponents: black-white, yellow-blue and green-red. The basic idea is that some cells of the visual system are excited by one of the opposing colors and inhibited by the other. Thus, a cell excited by wavelengths associated with green would be inhibited by wavelengths associated with red and vice versa. One of the implications of adversarial processing is that we don't perceive red-green or blue-yellow as colors. Another implication is that this leads to the experience of negative afterimages. An afterimage describes the persistence of a visual sensation after the stimulus is removed. For example, if you look briefly at the sun and then look away, you can still see a point of light even though the stimulus (the sun) has been removed. When color is involved in the stimulus, the color pairs identified in counterprocess theory result in a negative afterimage. You can test this concept with the flag in Figure 4-14.


Chapter 4 | sensation and perception

Figure 4.14 Stare at the white dot for 30 to 60 seconds and then move your eyes to a white piece of paper. What do you see? This is known as a negative afterimage and provides empirical support for the counterprocess theory of color vision.

But these two theories – the trichromatic theory of color vision and the counterprocess theory – are not mutually exclusive. Research has shown that they only apply to different levels of the nervous system. The trichromatic theory applies to visual processing in the retina: cones respond to three different wavelengths representing red, blue and green. However, once the signal passes through the retina on its way to the brain, the cells respond in a manner consistent with the opponent process theory (Land, 1959; Kaiser, 1997).

LINK TO LEARN Watch this video ( to learn more about color vision.

Depth Perception Our ability to perceive spatial relationships in three-dimensional (3-D) space is known as depth perception. With depth perception, we can describe things as in front of, behind, above, below, or beside other things. Our world is three-dimensional, so it makes sense that our mental representation of the world would have three-dimensional properties. We use a variety of cues in a visual scene to establish our sense of depth. Some of these are binocular cues, which means they rely on using both eyes. An example of binocular depth cue is binocular disparity, the slightly different view of the world that each of our eyes receives. To experience this slightly different view, do this simple exercise: Fully extend your arm and extend one finger and focus on that finger. Now close your left eye without moving your head, then open your left eye and close your right eye without moving your head. You'll notice that your finger appears to move when you switch between the two eyes, as each eye sees your finger slightly differently. A 3D movie works on the same principle: with special glasses you wear, you can see the two slightly different images projected onto the screen separately from your left and right eye. As your brain processes these images, you get the illusion that the jumping animal or running person is coming straight for you. While we rely on binocular cues to experience depth in our 3D world, we can also perceive depth in 2D matrices. Think of all the paintings and photographs you've seen. In general, you record the depth

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in these images, even though the visual stimulus is two-dimensional. When we do this, we rely on a series of monocular cues, or cues that only require one eye. If you think you can't see depth with one eye, note that walking with just one eye won't bump into things - and indeed, we have more monocular cues than binoculars. An example of monocular cue would be something called linear perspective. Linear perspective refers to the fact that we perceive depth when we see two parallel lines that appear to converge in an image (Figure 4.15). Some other monocular depth cues are interposition, partial overlapping of objects, and the relative size and proximity of images to the horizon.

Figure 4.15 We perceive depth in a two-dimensional picture like this one through the use of monocular cues like linear perspective, like the parallel lines that converge as the road narrows in the distance. (Image credit: Marc Dalmulder)

DIG DEEPER Stereo blindness Bruce Bridgeman was born with an extreme case of lazy eye which resulted in his stereo blindness or inability to respond to binocular depth cues. He relied heavily on monocular depth cues, but never had a real appreciation for the 3-D nature of the world around him. That all changed one night in 2012 when Bruce watched a movie with his wife. The movie the couple wanted to see was shot in 3-D, and although he thought it was a waste of money, Bruce paid for the 3-D glasses when he bought the ticket. As soon as the movie started, Bruce put on his glasses and experienced something completely new. For the first time in his life, he realized the true depth of the world around him. Remarkably, his ability to perceive depth persisted outside of film. There are cells in the nervous system that respond to binocular depth signals. Normally, these cells need to be activated during early development in order to survive, so experts familiar with Bruce's case (and others like his) theorize that Bruce must have experienced at least a fleeting moment of binocular vision at some point in his development. It was enough to ensure cell survival in the visual system attuned to binocular signals. The mystery now is why it took Bruce nearly 70 years to activate these cells (Peck, 2012).


Chapter 4 | sensation and perception

4.4 Learning Objectives Hearing By the end of this section, you will be able to: • describe the basic anatomy and function of the auditory system • explain how we encode and perceive tone • discuss how we localize sound Our auditory system converts pressure waves into meaningful signals , sounds. This leads to our ability to hear the sounds of nature, appreciate the beauty of music, and communicate with each other through spoken language. This section provides an overview of the basic anatomy and function of the auditory system. It will include a discussion of how sensory input is translated into neural impulses, where in the brain this information is processed, how we perceive pitch, and how we know where sound is coming from.

ANATOMY OF THE AUDITORY SYSTEM The ear can be divided into several sections. The outer ear includes the pinna, the visible part of the ear that protrudes from our head, the ear canal, and the eardrum or tympanic membrane. The middle ear contains three small bones known as the auditory ossicles, called the malleus (or malleus), anvil (or incus), and stirrup (or stirrup). The inner ear contains the semicircular canals involved in balance and movement (the sense of balance) and the cochlea. The cochlea is a fluid-filled, snail-shaped structure that contains the sensory receptor cells (hair cells) of the auditory system (Fig. 4.16).

Fig. 4.16 The ear is divided into external (pinna and eardrum), middle (the three ossicles: malleus, incus and stapes) and internal (cochlea and basilar membrane).

Sound waves travel through the ear canal and hit the eardrum, causing it to vibrate. This vibration causes the three ossicles to move. When the ossicles move, the stapes pushes against a thin membrane in the cochlea known as the oval window. When the stapes pushes into the oval window, the fluid in the cochlea begins to move, which in turn stimulates the hair cells, which are the inner ear's auditory receptor cells embedded in the basilar membrane. The basilar membrane is a thin strip of tissue inside the cochlea. Hair cell activation is a mechanical process: hair cell stimulation leads to this

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cell activation. When hair cells are activated, they generate neural impulses that travel along the auditory nerve to the brain. Auditory information is directed to the inferior colliculus, the medial geniculate nucleus of the thalamus, and finally to the auditory cortex in the temporal lobe of the brain for processing. As in the visual system, there is also evidence that auditory detection and localization information is processed in parallel streams (Rauschecker & Tian, ​​​​​​2000; Renier et al., 2009).

PERCEPTION OF SOUND Different frequencies of sound waves are associated with differences in our perception of the pitch of these sounds. Low frequency sounds are deeper and high frequency sounds are louder. How does hearing distinguish between different pitches? Several theories have been proposed to explain the perception of tone. We will discuss two of them here: the theory of time and the theory of place. The temporal theory of pitch perception states that pitch is encoded by the activity level of a sensory neuron. This would mean that a specific hair cell would fire action potentials related to the frequency of the sound wave. Although this is a very intuitive explanation, we see such a wide range of frequencies (20-20,000 Hz) that the frequency of action potentials triggered by hair cells cannot cover the entire range. Due to the properties of the sodium channels in the neuronal membrane involved in action potentials, there comes a point where a cell can no longer fire as quickly (Shamma, 2001). The localization theory of pitch perception suggests that different parts of the basilar membrane are sensitive to sounds of different frequencies. More specifically, the base of the basilar membrane responds best to high frequencies and the apex of the basilar membrane responds best to low frequencies. Therefore, hair cells located at the basal portion would be labeled as high-frequency receptors, while those at the apex of the basilar membrane would be labeled as low-frequency receptors (Shamma, 2001). In reality, both theories explain different aspects of pitch perception. At frequencies up to about 4000 Hz, it is clear that both the frequency and the location of the action potential contribute to our perception of tone. However, much higher frequency tones can only be encoded using place cues (Shamma, 2001).

SOUND LOCALIZATION The ability to localize sounds in our environment is an important part of hearing. Sound localization can be thought of as similar to how we perceive depth in our visual fields. Like monocular and binocular cues that provide depth information, the hearing aid uses monaural (one ear) and binaural (two ears) cues to localize sound. Each pavilion interacts differently with incoming sound waves, depending on the sound source in relation to our body. This interaction provides a monaural cue that is useful for locating sounds that occur above or below and in front of or behind us. The sound waves received by your two ears from sounds directly above, below, in front of, or behind you would be identical; Therefore, monaural cues are essential (Grothe, Pecka & McAlpine, 2010). Binaural cues, on the other hand, provide information about the position of a sound along a horizontal axis, based on differences in eardrum vibration patterns between our two ears. When a sound comes from an off-center position, it creates two types of binaural cues: interaural level differences and interaural time differences. The interaural level difference refers to the fact that a sound coming from the right side of the body is louder in the right ear than in the left ear because the sound wave is attenuated as it passes through the head. The interaural time difference refers to the small difference in time for a given sound wave to reach each ear (Figure 4.17). Specific areas of the brain monitor these differences to construct where a sound originates along a horizontal axis (Grothe et al., 2010).


Chapter 4 | sensation and perception

Figure 4.17 Sound localization involves the use of both mono and binaural cues. (Credit "Avião": Modification of the work by Max Pfandl)

HEARING LOSS Deafness is the partial or total inability to hear. Some people are born deaf, which is known as congenital deafness. Many others begin to suffer because of age, genetics, or environmental influences, including exposure to extreme noise (noise-induced hearing loss, as shown in Figure 4.18), certain illnesses (such as measles or mumps), or conductive hearing loss and toxin damage. (such as those found in certain solvents and metals).

Figure 4.18 Environmental factors that can lead to conductive hearing loss are regular exposure to loud music or construction machinery. (a) rock musicians and (b) construction workers are at risk for this type of hearing loss. (Credit a: Modification of work by Kenny Sun; Credit b: Modification of work by Nick Allen)

Given the mechanical nature by which the sound wave stimulus is transmitted from the eardrum through the ossicles to the oval window of the cochlea, some degree of hearing loss is inevitable. In conductive hearing loss, hearing problems are associated with loss of eardrum vibration and/or ossicle movement. These problems are usually treated with devices, such as hearing aids, that amplify incoming sound waves to make the eardrum vibrate and the ossicles more likely to move.

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to happen. When the hearing problem is associated with an interruption in the transmission of nerve signals from the cochlea to the brain, it is called sensorineural hearing loss. One disease that causes sensorineural hearing loss is Meniere's disease. Although not well understood, Ménière's disease causes degeneration of inner ear structures that can lead to hearing loss, tinnitus (constant buzzing or buzzing), dizziness (spinning sensation), and increased pressure in the inner ear (Semaan & Megarian, 2011). This type of loss cannot be treated with hearing aids, but some individuals may be candidates for a cochlear implant as a treatment option. Cochlear implants are electronic devices consisting of a microphone, a speech processor and an array of electrodes. The device takes incoming sound information and directly stimulates the auditory nerve to transmit information to the brain.

LINK TO LEARN Watch this video ( which describes cochlear implant surgery and how it works.

WHAT DO YOU THINK? Deaf Culture In the United States and elsewhere in the world, Deaf people have their own language, schools, and customs. It's called deaf culture. In the United States, deaf people often communicate using American Sign Language (ASL); ASL has no verbal component and is based only on visual signs and gestures. The main mode of communication is subscription. One of the values ​​of deaf culture is to continue traditions such as the use of sign language, rather than teaching deaf children to try to speak, lip-read, or undergo cochlear implant surgery. When a child is diagnosed as deaf, parents face difficult decisions. Should the child be enrolled in mainstream schools and learn to verbalize and lip read? Or should the child be sent to a school for deaf children to learn ASL and have significant exposure to Deaf culture? Do you think there might be differences in how parents approach these decisions depending on whether or not they are also deaf?

4.5 The Other Senses Learning Objectives By the end of this section you will be able to: • describe the basic functions of the chemical senses • explain the basic functions of the somatosensory, nociceptive and thermoceptive sensory systems • the basic functions of the vestibular, proprioceptive and sensory systems kinesthetics Vision and hearing have become amazing over the years and have received a lot of attention from researchers. While there is still much to learn about how these sensory systems work, we have a much better understanding of them than our other sensory modalities. In this section, we'll explore our chemical senses (taste and smell) and our bodily senses (touch, temperature, pain, balance, and posture).


Chapter 4 | sensation and perception

THE CHEMICAL SENSES Taste (taste) and smell (smell) are called chemical senses because they both have sensory receptors that respond to molecules in the food we eat or the air we breathe. There is a distinct interplay between our chemical senses. For example, when we describe the taste of a certain food, we are actually referring to the gustatory and olfactory properties of the food, working together.

Tasting You learned in elementary school that there are four basic taste groups: sweet, salty, sour, and bitter. However, research shows that we have at least six taste groups. Umami is our fifth flavor. Umami is actually a Japanese word that roughly translates to tasty and is associated with a predilection for MSG (Kinnamon & Vandenbeuch, 2009). There is also a growing body of experimental evidence suggesting that we have a taste for the fat content of a given food (Mizushige, Inoue & Fushiki, 2007). Molecules in the food and drink we consume dissolve in our saliva and interact with taste receptors in our tongue, mouth and throat. Taste buds are formed by clusters of taste receptor cells with hair-like projections that project into the central pore of the taste bud (Figure 4.19). Taste buds have a life cycle of ten days to two weeks, so even destroying a few by burning your tongue has no long-term effects; they just grow back. To that extent, taste molecules bind to receptors and cause chemical changes within the sensory cell that cause nerve impulses to travel through different nerves to the brain, depending on where the receptor is located. Gustatory information is transmitted to the medulla, thalamus, and limbic system, as well as to the gustatory cortex, located under the overlap between the frontal and temporal lobes (Maffei, Haley, & Fontanini, 2012; Roper, 2013).

Figure 4.19 (a) The taste buds are formed by a series of individual taste receptor cells that transmit information to the nerves. (b) This micrograph shows a close-up of the surface of the tongue. (Credit a: Modification of work by Jonas Töle; Credit b: Scale bar data by Matt Russell)

Odor (Olfaction) The olfactory receptor cells are located in a mucous membrane at the top of the nose. Small, hairlike extensions of these receptors serve as sites for odor molecules dissolved in mucus to interact with the chemical receptors located on these extensions (Figure 4.20). After an odorant molecule binds to a specific receptor, chemical changes within the cell cause signals to be sent to the olfactory bulb: a bulb-like structure at the top of the frontal lobe, where the olfactory nerves begin. Information is sent from the olfactory bulb to regions of the limbic system and to the primary olfactory cortex, which is very close to the gustatory cortex (Lodovichi & Belluscio, 2012; Spors et al., 2013).

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Fig. 4.20 The olfactory receptors are the hairlike parts that extend from the olfactory bulb to the mucosa of the nasal cavity.

There are huge differences in the sensitivity of the olfactory systems of different species. We often think that dogs have a much superior olfactory system than ours, and in fact, dogs can do remarkable things with their noses. There is evidence that dogs can "smell" dangerous blood sugar drops as well as cancerous tumors (Wells, 2010). The exceptional olfactory abilities of dogs may be due to the increased number of functional genes for olfactory receptors (between 800 and 1200) compared to the less than 400 observed in humans and other primates (Niimura & Nei, 2007). Many species respond to chemical messages, known as pheromones, sent by another individual (Wysocki & Preti, 2004). Pheromonal communication usually involves providing information about a potential mate's reproductive status. For example, when a female rat is ready to mate, she secretes pheromone signals that attract the attention of nearby male rats. Indeed, pheromone activation is an important component in triggering sexual behavior in male rats (Furlow, 1996, 2012; Purvis & Haynes, 1972; Sachs, 1997). There has also been much research (and controversy) about pheromones in humans (Comfort, 1971; Russell, 1976; Wolfgang-Kimball, 1992; Weller, 1998).

TOUCH, THERMOCEPTION, AND NOCICEPTION Various receptors are distributed throughout the skin to respond to various touch-related stimuli (Figure 4.21). These receptors include Meissner bodies, Pacini bodies, Merkel disks, and Ruffini bodies. Meissner's corpuscles respond to lower frequency pressure and vibration, and Pacinian corpuscles detect higher frequency transient pressure and vibration. Merkel's intervertebral discs respond to light pressure, while Ruffini's bodies feel the stretch (Abraira & Ginty, 2013).


Chapter 4 | sensation and perception

Figure 4.21 There are many types of sensory receptors in the skin, each tuned to specific touch-related stimuli.

In addition to the receptors located in the skin, there are also several free nerve endings that serve sensory functions. These nerve endings respond to a variety of different types of touch-related stimuli and serve as sensory receptors for thermoception (temperature perception) and nociception (a signal that indicates potential harm and possible pain) (Garland, 2012; Petho & Reeh, 2012 ; Spray, 1986). Sensory information collected by receptors and free nerve endings travels up the spinal cord and is transmitted to regions of the medulla, thalamus, and finally to the somatosensory cortex, located in the postcentral gyrus of the parietal lobe.

Pain perception Pain is an unpleasant experience that includes both physical and psychological components. Feeling pain is very adaptive because it alerts us to an injury and motivates us to move away from the cause of that injury. Also, pain makes us less likely to sustain additional injuries because we are kinder to our injured body parts. In general, pain can be considered neuropathic or inflammatory in nature. Pain that indicates tissue damage is called inflammatory pain. In some situations, pain results from damage to neurons in the peripheral or central nervous system. As a result, pain signals sent to the brain become exaggerated. This type of pain is called neuropathic pain. A wide range of treatment options for pain relief range from relaxation therapy to the use of analgesics and deep brain stimulation. The most effective treatment option for any particular individual depends on several considerations, including the severity and duration of pain and any medical/psychological conditions. Some people are born without the ability to feel pain. This very rare genetic disorder is known as congenital insensitivity to pain (or congenital analgesia). While those with congenital analgesia can detect differences in temperature and pressure, they do not feel pain. As a result, they often suffer serious injuries. Young children have serious injuries to their mouth and tongue from repeatedly biting themselves. Not surprisingly, individuals suffering from this disorder have a much shorter life expectancy due to injuries and secondary infections at injured sites (US National Library of Medicine, 2013).

LINK TO LEARN Watch this video ( to learn more about congenital pain insensitivity.

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VESTIBULAR SENSES, PROPRIOCEPTION, AND KINETHESIA The vestibular sense contributes to our ability to maintain balance and posture. As shown in Fig. 4.22, the most important sensory organs (utricle, saccule, and the three semicircular canals) of this system are located near the cochlea in the inner ear. The vestibular organs are filled with fluid and have hair cells, similar to those in the auditory system, which respond to head movement and gravitational forces. When these hair cells are stimulated, they send signals to the brain via the vestibular nerve. Although we may not be aware of the sensory information from our vestibular system under normal circumstances, its importance becomes apparent when we experience motion sickness and/or vertigo associated with inner ear infections (Khan & Chang, 2013).

Fig. 4.22 The most important sensory organs of the vestibular system are located near the cochlea in the inner ear. These include the utricle, the saccule, and the three semicircular canals (posterior, superior, and horizontal).

In addition to maintaining balance, the vestibular system collects important information to control movement and the reflexes that move different parts of our body to compensate for changes in body position. Therefore, both proprioception (perception of body position) and kinesthesia (perception of body movement in space) interact with the information provided by the vestibular system. These sensory systems also collect information from receptors that respond to stretching and tension in muscles, joints, skin, and tendons (Lackner & DiZio, 2005; Proske, 2006; Proske & Gandevia, 2012). Proprioceptive and kinesthetic information travels through the spine to the brain. In addition to the cerebellum, several cortical regions receive and send information to Organs sensory organs of the proprioceptive and kinesthetic systems.

4.6 Gestalt Principles of Perception Learning Objectives By the end of this section, you will be able to: • explain the figure-ground relationship • define gestalt grouping principles • describe how the perceptual set is affected by a person's characteristics and mental state Starting at No In the late 20th century, Max Wertheimer published a paper showing that people perceive motion in rapidly flashing still images - a perception he gained by using a child's toy


Chapter 4 | sensation and perception

tachistoscope. Wertheimer and his assistants, Wolfgang Köhler and Kurt Koffka, who later became his partners, believed that perception was more than the mere combination of sensory stimuli. This belief led to a new movement in the field of psychology known as Gestalt psychology. The word gestalt literally means form or pattern, but its use reflects the idea that the whole is different from the sum of its parts. In other words, the brain creates a perception that is more than just the sum of available sensory information, and it does so in predictable ways. Gestalt psychologists translated these predictable pathways into principles by which we organize sensory information. As a result, Gestalt psychology has been extremely influential in the field of sensation and perception (Rock & Palmer, 1990). A design principle is the figure-ground relationship. According to this principle, we tend to segment our visual world into figure and ground. Figure is the object or person that is the focus of the field of view, while background is the background. As Figure 4.23 shows, our perception can vary greatly between what is perceived as figure and what is perceived as ground. Presumably, our ability to interpret sensory information depends on what we call the figure and what we call the ground, although this assumption has been challenged (Peterson & Gibson, 1994; Vecera & O'Reilly, 1998).

Figure 4.23 The concept of the figure-ground relationship explains why this image can be perceived both as a vase and as a pair of faces.

Another gestalt principle for organizing sensory stimuli into meaningful cognition is proximity. This principle states that things that are close together tend to cluster together, as shown in Figure 4.24.

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Chapter 4 | sensation and perception


Figure 4.24 The gestalt principle of proximity suggests that you see (a) a block of dots on the left and (b) three columns on the right.

How we read something is another example of the concept of proximity. For example, we read this sentence like this, not as iket hiso rt. We group the letters of a given word together because there are no spaces between the letters, and we perceive words because there are spaces between the words. Here are some more examples: Cany oum akes enseo ft hiss entence? What do these words mean? We could also use the similarity principle to group things in our visual fields. According to this principle, similar things are grouped together (Figure 4.25). For example, when we watch a football game, we tend to group people based on their uniform colors. If we observe an offensive drive, we can get a picture of the two teams simply by grouping them in this dimension.

Figure 4.25 Looking at this arrangement of dots, we are likely to notice rows of alternating colors. We group these points according to the principle of similarity.

Two other gestalt principles are the law of continuity (or good continuation) and conclusion. The law of continuity suggests that we perceive continuous, smooth flowing lines rather than jagged, broken lines (Figure 4.26). The principle of closure states that we organize our perceptions into complete objects rather than a series of parts (Figure 4.27).


Chapter 4 | sensation and perception

Figure 4.26 A good continuation would indicate that we perceive this as two lines overlapping rather than four lines meeting in the middle.

The closure of Figure 4.27 suggests that we will perceive a complete circle and rectangle rather than a series of segments.

LINK TO LEARN Watch this video ( to see real illustrations of Gestalt principles.

According to gestalt theorists, our perception of patterns, or our ability to distinguish between different figures and shapes, occurs following the principles described above. You are probably sure that what you perceive corresponds exactly to the real world, but this is not always the case. Our perceptions are based on perceptual assumptions: reasoned assumptions we make when interpreting sensory information. These hypotheses are based on many factors, including our personality, experiences and expectations. We use these assumptions to generate our perceptual set. For example, research has shown that those who receive verbal priming produce a biased interpretation of complex ambiguous numbers (Goolkasian & Woodbury, 2010).

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Chapter 4 | sensation and perception

DEEPER THE DEPTHS OF PERCEPTION: BIAS, PREJUDICE, AND CULTURAL FACTORS In this chapter you learned that perception is a complex process. Constructed of sensations, but influenced by our own experiences, prejudices, prejudices and cultures, perceptions can vary greatly from person to person. Research suggests that implicit racial bias and stereotypes influence perception. For example, several studies have shown that when the gun image is paired with the image of a black person, non-black participants are more likely to identify weapons and identify non-weapons as weapons (Payne, 2001; Payne, Shimizu, and Jacobi, 2005). Furthermore, whites' decisions to shoot an armed target in a video game are made more quickly when the target is black (Correll, Park, Judd, & Wittenbrink, 2002; Correll, Urland, & Ito, 2006). This research is important given the number of well-publicized cases over the last few decades of young black men being killed by people who claimed to believe that unarmed individuals were armed and/or posed a threat to their personal safety.



Chapter 4 | sensation and perception

Key terms absolute threshold minimum amount of stimulus energy that must be present for the stimulus to be recognized 50% of the time after imaging continuation of a visual sensation after stimulus removal amplitude height of a waveform basilar membrane thin strips of tissue inside of the cochlea containing the hair cells that act as sensory receptors to serve the auditory system binaural cue binaural cue to localize sound binocular cue based on the use of both eyes binocular disparity slightly different view of the world each eye receives blind spot spot where we cannot access visual information in that part of the visual field's bottom-up processing system, where perceptions are constructed from closures of sensory input that organize our perceptions into complete objects, rather than a series of parts that make up a shaped structure fluid-filled snail shell contains the sensory receptor cells of the system a cochlear implant electronic device composed of a microphone and a speech processor and a series of electrodes to directly stimulate the auditory nerve to transmit information to the brain detects color congenital deafness deafness from birth congenital insensitivity to pain (congenital analgesia) disorder genetic that leads to inability to feel pain corneal transparent covering of the eye partial or total deafness inability to hear decibel (dB) logarithmic unit of sound intensity depth perception ability electromagnetic spectrum The total electromagnetic radiation emitted in our environment occurs in figure-background relationship segmentation of our visual world into figure and ground fovea a small depression in the retina containing cones frequency number of waves passing a given point in a given period psychic form hology area of ​​psychology based on the idea that the whole is different from the sum of its parts good continuation (also continued ity) We tend to perceive continuous and flowing lines

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Chapter 4 | sensation and perception


jagged, broken lines Hair cell Inner ear auditory receptor cell Hertz (Hz) cycles per second; Measuring the frequency of unintentional blindness Not paying attention to something fully visible due to lack of attention Incus ossicles; also known as inflammation of the incus pain Sign that some type of tissue damage has occurred interaural level difference Sound coming from one side of the body is louder in the nearest ear because the sound wave is attenuated as it passes through the head at the time a certain sound wave arrives in each ear colored part of the iris of the eye difference barely perceptible difference in stimuli needed to detect a difference between stimuli kinesthetic perception of body movement through spatial lens curved transparent structure that provides additional focus for light to enter the linear perspective of the eye perceiving depth in an image when two parallel lines appear to converge hammering the middle ear ossicles; also known as Meissner Hammer Corpuscle Touch Receiver, which responds to pressure and low-frequency vibration Merkel Disc Touch Receiver, which responds to light touch Monaural Signaling Monaural Signaling for Sound Localization Monocular Signaling Requiring Only One Eye A Meniere's disease causes degeneration of inner ear structures that can lead to hearing loss, tinnitus, dizziness and increased pressure in the inner ear Neuropathic pain Pain caused by damage to neurons in the peripheral or central nervous system Nociception Sensory signal indicating potential damage and possible pain olfactory bulb pear-like structure at the tip of the frontal lobe, where the olfactory nerves begin Olfactory receptor Sensory cell for the olfactory system Counterprocess Theory of color perception Color is coded in pairs: black-white, yellow-blue, and red-green Optic chiasm X-shaped structure located just below the ve surface ie ntral of the brain stands; represents the fusion of the optic nerves of the two eyes and the separation of information from the two sides of the visual field to the opposite side of the brain. The optic nerve carries visual information from the retina to the brain. Pacini body touch receiver that detects transient pressure and higher frequency vibrations


Chapter 4 | sensation and perception

pattern perception ability to distinguish between different shapes and shapes crest (also crest) highest point of a wave cognition way in which sensory information is interpreted and consciously experienced perceptual hypothesis educated guess about interpretation of sensory information pheromone chemical message sent by another individual photoreceptor becomes pinna light detection visible part of the ear protruding from the head perceiving the pitch of the frequency of a sound theory of perception different parts of the basilar membrane are sensitive to sounds of different frequencies closure principle organizes perceptions into whole objects rather than a set of parts proprioception perception body position proximity things that are close together tend to clump together pupil small opening in the eye through which light passes photosensitive retina retinal rod-eye coating specialized photoreceptor that works well in low light z Corpuscles of Ruffini touch receptor that detects a stretching sensation what happens when sensory information is sensed by a sensory receptor sensorineural hearing loss failure to transmit neural signals from the cochlea to the brain sensory adaptation stimuli fail perceptions that remain relatively constant over long periods of time signal recognition theory change in stimulus recognition due to similarity of current mental state things that are similar tend to be grouped together stapes middle ear ossicles; also known as stapes subliminal message message presented below the threshold of conscious awareness taste bud cluster of taste receptor cells with hair-like extensions projecting from the central pore of the taste bud temporal theory of pitch perception the frequency of the pitch is encoded by the level of activity of a sensory neuron thermoception temperature perception timbre purity of sound top-down processing Interpretation of sensations is influenced by available knowledge, experience and thinking

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Chapter 4 | sensation and perception


Transduction Conversion of sensory stimulus energy into action potential Trichromatic theory of color vision Color vision is mediated by activity in all three sets of cones across the nadir of a wave Maintain balance and posture Maintain the visible portion of the spectrum electromagnetic we can see the wavelength of a wave from one peak to the next peak

Summary 4.1 Sensation versus Perception Sensation occurs when sensory receptors perceive sensory stimuli. Perception involves the organization, interpretation, and conscious experience of these sensations. All sensory systems have absolute and difference thresholds, which refer to the minimum amount of stimulus energy, or the minimum amount of difference in stimulus energy, required to be detected about 50% of the time. Sensory adaptation, selective attention, and signal recognition theory can help explain what is and is not perceived. Furthermore, our perception is influenced by a number of factors, including beliefs, values, prejudices, culture and life experiences. 4.2 Waves and Wavelengths Both light and sound can be described by waveforms with physical properties such as amplitude, wavelength and timbre. Wavelength and frequency are inversely related, so longer waves have lower frequencies and shorter waves have higher frequencies. In the visual system, the wavelength of a light wave is generally associated with color and its amplitude with brightness. In the auditory system, the frequency of a sound is related to its pitch and its amplitude to its volume. 4.3 Vision Light waves pass through the cornea and enter the eye through the pupil. The eye's lens concentrates this light so that the image is focused on an area of ​​the retina known as the fovea. The fovea contains cones, which have high visual acuity and work best in bright light. Rods are located throughout the retina and work best in low light. Visual information leaves the eye via the optic nerve. Information from each visual field is sent to the opposite side of the brain at the intersection of the optic nerve. The visual information then travels through a series of brain sites before reaching the occipital lobe, where it is processed. Two theories explain the perception of colors. The trichromatic theory states that three different sets of cones are tuned to slightly different wavelengths of light, and it is the combination of the activity of these types of cones that drives our perception of all the colors we see. The counterprocess theory of color vision states that color is processed in counterparts and explains the interesting phenomenon of a negative afterimage. We perceive depth through a combination of monocular and binocular depth signals. 4.4 Hearing Sound waves are directed into the ear canal and make the eardrum vibrate; these vibrations move the auditory ossicles. When the ossicles move, the stapes pushes on the oval window of the cochlea, the


Chapter 4 | sensation and perception

causes the fluid in the cochlea to move. This increases the hair cells embedded in the basilar membrane, which send nerve impulses to the brain via the auditory nerve. Pitch perception and sound localization are important aspects of hearing. Our ability to perceive tone depends on both the rate of firing of hair cells on the basilar membrane and their position within the membrane. In terms of sound localization, mono and binaural cues are used to localize where sounds originate in our environment. Individuals can be born deaf or develop deafness due to age, genetics and/or environmental factors. Hearing loss that results from a failure of the eardrum to vibrate or the resulting movement of the auditory ossicles is called conductive hearing loss. A hearing loss in which the transmission of auditory nerve impulses to the brain fails is called sensorineural hearing loss. 4.5 The other senses Taste (taste) and smell (smell) are chemical senses that use receptors on the tongue and nose that connect directly to taste and smell molecules to transmit information to the brain for processing. Our ability to sense touch, temperature, and pain is mediated by a series of receptors and free nerve endings that are distributed throughout the skin and various tissues of the body. The vestibular sense helps us maintain a sense of balance through the response of hair cells in the utricle, saccule, and semicircular canals that respond to changes in head position and gravity. Our proprioceptive and kinesthetic systems provide information about the body's position and movement through receptors that detect stretch and tension in the body's muscles, joints, tendons, and skin. 4.6 Gestalt principles of perception Gestalt theorists have been incredibly influential in the fields of sensation and perception. Gestalt principles such as figure-ground relationships, grouping by proximity or similarity, the law of good continuation and closure are all used to explain how we organize sensory information. Our perceptions are not infallible and can be influenced by biases, prejudices and other factors.

Knowledge Review 1. ________ refers to the minimum amount of stimulus energy needed to be detected 50% of the time. one. absolute threshold b. difference limit c. only noticeable difference d. streaming

4. ________ occurs when sensory information is consciously organized, interpreted, and experienced. one. feeling b. perception c. transmission D. sensory adaptation

2. Decreased sensitivity to a fixed stimulus is referred to as ________. one. transfer b. difference limit c. sensory adaptation d. inattentional blindness

5. Which of the following statements correctly matches our pattern of perceiving colors as we move from short to long wavelengths? one. red to orange to yellow b. yellow to orange to red c. yellow to red to orange d. orange to yellow to red

3. ________ involves the conversion of sensory stimulus energy into neural impulses. one. sensory adaptation b. accidental blindness c. difference limit d. streaming

6. The visible spectrum includes light in the range of approximately ________. one. 400-700 nm b. 200-900 nm c. 20-20000Hz d. 10-20dB

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Chapter 4 | sensation and perception


7. The electromagnetic spectrum includes ________. one. radio waves b. X-rays c. infrared light d. all of the above

14. Hair cells near the base of the basilar membrane respond best to ________ sounds. one. low frequency b. high frequency c. low amplitude d. high amplitude

8. The audible range for humans is ________. one. 380-740 Hz b. 10-20dB c. less than 300dB d. 20-20,000 Hertz

15. The three ossicles in the middle ear are known as the ________. one. hammer, anvil and stirrup b. Hammer, anvil and stirrup c. Auricle, cochlea and utricle d. Not just A but also B

9. The quality of a sound, which is affected by the frequency, amplitude and time of the sound wave, is known as ________. one. pitch b. clay c. electromagnetic d. timbre

16. Hearing aids can be effective in treating ________. one. Meniere's disease b. sensorineural hearing loss c. conductive hearing loss d. interaural time differences

10. The ________ is a small depression in the retina that contains cones. one. optic chiasm b. optic nerve c. fovea d. iris

17. Cues that require two ears are called ________ cues. one. monocular b. monophonic c. D. binaural binoculars

11. ________ work best in bright light. one. cone b. rods c. retinal ganglion cells d. striped cortex

18. The chemical messages, often sent between two members of a species to communicate something about the reproductive state, are called ________. one. hormones b. pheromones c. Merkel disks d. Meissner corpuscles

12. ________ Depth cues require the use of both eyes. one. monocular b. binoculars c. linear perspective d. accommodating 13. If you looked at a green dot for a relatively long time and then shifted your gaze to a blank white screen, you would see a ________ negative afterimage. one. blue b. yellow c. black d. red

19. What flavor is associated with MSG? one. sweet b bitter c. umami d. acid 20. ________ serve as sensory receptors for temperature and pain stimuli. one. free nerve endings b. pacinian bodies c. Bodies of Ruffini d. Meissner corpuscles


21. Which of the following factors is involved in maintaining balance and posture? one. auditory nerve B. nociceptors c. olfactory bulb D. vestibular system 22. According to the ________ principle, objects that are close together tend to be grouped together. one. similarity b. good continuation c. near d. close

Chapter 4 | sensation and perception

24. According to the Law of ________, we are more likely to perceive smooth flowing lines than jagged or jagged lines. one. closure b. good continuation c. near d. Similarity 25. The main focus in a visual display is known as ________. one. closure b. perception set c. floor D. Number

23. Our tendency to perceive things as complete objects rather than a series of parts is known as the ________ principle. one. closure b. good continuation c. near d. resemblance

Critical Thinking Issues 26. Not everything that gets noticed gets noticed. Do you think there could be a case where something could be perceived without being felt? 27. Generate a new example of how a barely perceptible difference can change as a function of stimulus intensity. 28. Why do you think other species have such different levels of sensitivity to visual and auditory stimuli compared to humans? 29. Why do you think people are particularly sensitive to sounds with frequencies in the middle of the audible range? 30. Compare the two theories of color perception. Are they completely different? 31. Color is not a physical property of our environment. What function (if any) do you think color vision has? 32. Given what you've read about sound localization, how does sound localization facilitate survival from an evolutionary perspective? 33. How can the theories of time and space be used to explain our ability to perceive the pitch of sound waves with frequencies up to 4000 Hz? 34. Many people feel nauseous when traveling by car, plane or boat. How can this be explained in terms of sensory interaction?

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Chapter 4 | sensation and perception


35. If you heard someone say that they would do anything to avoid the pain associated with a serious injury, how would you react to what you just read? 36. Do you think women feel pain differently than men? Why do you think this is? 37. The central tenet of Gestalt psychology is that the whole is distinct from the sum of its parts. What does this mean in the context of perception? 38. Observe the figure below. How could you influence whether people see a duck or a rabbit?

Figure 4.28

Personal Application Questions 39. Think of a time when you failed to notice something around you because your attention was elsewhere. If someone pointed this out, were you surprised that you didn't notice it right away? 40. If you grew up with a pet, you've probably noticed that they often seem to hear things you don't. After reading this section, you will probably have some idea why this might happen. How would you explain this to a friend who never had the opportunity to take such a course? 41. View some of your personal photos or artwork. Can you find examples of linear perspective as a potential depth indication? 42. If you had to choose between losing your eyesight or your hearing, which would you choose and why? 43. As mentioned earlier, the taste of a food is an interplay of taste and smell information. Think about the last time you had a severe cold due to a cold or the flu. What changes did you notice in the taste of the foods you ate during this time? 44. Have you ever heard a song on the radio and sang along only to find out you sang the wrong lyrics? Did your perception of the song change after you found the right lyrics?


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Chapter 4 | sensation and perception

Chapter 5 | states of consciousness


chapter 5

states of consciousness

Figure 5.1 Sleep, which we all experience, is a silent and mysterious lull in our daily lives. Two sleeping children are depicted in this 1895 oil painting entitled Two Sleeping Girls on the Stove Bench by Swiss painter Albert Anker.

Chapter 5.1 Overview What is conscience? 5.2 Sleep and why we sleep 5.3 Stages of sleep 5.4 Sleep problems and disorders 5.5 Substance use and abuse 5.6 Other states of consciousness

Introduction Our lives involve regular and dramatic changes in the degree to which we are aware of our environment and our internal states. While awake, we feel awake and aware of the many important things happening around us. Our experiences change dramatically while we are in deep sleep and again when we are dreaming. This chapter discusses states of consciousness with a particular focus on sleep. The different stages of sleep are identified and sleep disorders are described. The chapter ends with discussions of altered states of consciousness induced by psychoactive drugs, hypnosis, and meditation.


Chapter 5 | states of consciousness

5.1 What is conscience? Learning objectives By the end of this section, you will be able to: • understand what consciousness means • explain how circadian rhythms are involved in regulating the sleep-wake cycle and how circadian cycles can be disrupted • discuss the concept of debt consciousness sleep describes our awareness to internal and external stimuli. Awareness of internal stimuli includes feeling pain, hunger, thirst, drowsiness, and awareness of our thoughts and emotions. Awareness of external stimuli includes seeing sunlight, feeling the heat in a room, and hearing a friend's voice. We regularly experience different states of consciousness and different levels of consciousness. We could even describe consciousness as a continuum from full consciousness to deep sleep. Sleep is a state characterized by relatively little physical activity and reduced sensory perception, distinct from periods of rest that occur during wakefulness. Alertness is characterized by a high level of sensory perception, thinking and behavior. Between these extremes are states of consciousness associated with daydreaming, states of intoxication resulting from alcohol or drug use, meditative states, hypnotic states, and altered states of consciousness following sleep deprivation. We can also experience unconscious states through drug-induced anesthesia for medical purposes. Often, we are not fully aware of our surroundings, even when we are fully awake. For example, have you ever had a dream while driving home from work or school without really thinking about the drive itself? They were able to take on all the complex tasks involved in driving a motor vehicle without even realizing it. Many of these processes, like much psychological behavior, are rooted in our biology.

BIOLOGICAL RHYTHMS Biological rhythms are internal rhythms of biological activity. A woman's menstrual cycle is an example of a biological rhythm - a cyclical, recurring pattern of bodily changes. A full menstrual cycle lasts about 28 days – a lunar month – but many biological cycles are much shorter. For example, body temperature varies cyclically over a 24-hour period (Figure 5.2). Alertness is associated with higher body temperatures and drowsiness with lower body temperatures.

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Chapter 5 | states of consciousness


Figure 5.2 This graph illustrates the circadian change in body temperature over 28 hours in a group of eight young men. Body temperature rises throughout the day, peaking in the afternoon and dropping during sleep, with the lowest point occurring in the early morning hours.

This pattern of temperature fluctuations that repeats itself every day is an example of a circadian rhythm. A circadian rhythm is a biological rhythm that occurs over a period of approximately 24 hours. Our sleep-wake cycle, linked to the natural light-dark cycle of our environment, is perhaps the most obvious example of a circadian rhythm, but we also have daily fluctuations in heart rate, blood pressure, blood sugar and body temperature. Some circadian rhythms play a role in changes in our state of consciousness. If we have biological rhythms, is there some kind of biological clock? In the brain, the hypothalamus, which sits above the pituitary gland, is an important center of homeostasis. Homeostasis is the tendency to maintain an optimal balance or level within a biological system. The brain clock mechanism is located in an area of ​​the hypothalamus known as the suprachiasmatic nucleus (SCN). The axons of photosensitive neurons in the retina provide information to the SCN based on the amount of light present, allowing this internal clock to be synchronized with the outside world (Klein, Moore, & Reppert, 1991; Welsh, Takahashi, & Kay, 2010) ( Figure 5.3).


Chapter 5 | states of consciousness

Figure 5.3 The suprachiasmatic nucleus (SCN) functions as the engine of the brain. The watch adjusts itself using light information received through retinal projections.

PROBLEMS WITH CIRCADIAN RHYTHMS In general, and for most people, our circadian cycles are aligned with the outside world. For example, most people sleep at night and are awake during the day. An important regulator of the sleep-wake cycle is the hormone melatonin. The pineal gland, an endocrine structure in the brain that releases melatonin, is thought to be involved in regulating various biological rhythms and the immune system during sleep (Hardeland, Pandi-Perumal & Cardinali, 2006). Melatonin release is stimulated by darkness and inhibited by light. There are individual differences in our sleep-wake cycle. For example, some people would describe themselves as morning people, while others would describe themselves as night people. These individual differences in circadian activity patterns are known as a person's chronotype, and research shows that morning and night people differ in terms of sleep regulation (Taillard, Philip, Coste, Sagaspe, & Bioulac, 2003). Sleep regulation refers to the brain's control over the alternation between sleep and wakefulness and the coordination of this cycle with the outside world.

LINK TO LEARN Watch this short video ( that describes circadian rhythms and their impact on sleep.

Disruptions in Normal Sleep Whether it's a lark, an owl, or something in between, there are times when a person's circadian clock is out of sync with the external environment. One way to achieve this is by crossing multiple time zones. When we do this, we often experience jet lag. Jet lag is a collection of symptoms that result from the discrepancy between our internal circadian cycles and our environment. These symptoms include fatigue, sluggishness, irritability, and insomnia (ie, persistent difficulty falling asleep or staying asleep at least three nights a week for a month) (Roth, 2007). Individuals who work rotating shifts are also prone to disruptions in their circadian cycles.

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Chapter 5 | states of consciousness


Rotating shift work means a work schedule that changes from morning to evening on a daily or weekly basis. For example, a person can work from 7 am to 3 pm. on Monday, from 3:00 am to 11:00 am on Tuesday and from 11:00 am to 7:00 pm on Wednesday. In these cases, the person's schedule changes so often that it becomes difficult to maintain a normal circadian rhythm. This often leads to trouble sleeping and can lead to signs of depression and anxiety. These types of schedules are common among people working in health care and service sectors and are associated with persistent feelings of exhaustion and excitement, which can make a person more likely to make mistakes at work (Gold et al., 1992; Presser, 1995). Rotating shift work has far-reaching implications for the lives and experiences of those employed in this type of work, which is clearly illustrated in stories reported in a qualitative study that examined the experiences of middle-aged nurses working rotating shifts. (West, Boughton and Byrnes, 2009). Several of the nurses interviewed indicated that their working hours affected their relationships with their families. One of the nurses said: If you had a partner who works a regular 9-5 hour shift. 🇧🇷 🇧🇷 the ability to spend quality time with them when you're not feeling downright exhausted. 🇧🇷 🇧🇷 this would be one of the problems I encountered. (West et al., 2009, p. 114) While circadian rhythm disruptions can have negative consequences, there are things we can do to help us realign our biological clocks with the external environment. Some of these approaches, such as using a bright light as shown in Figure 5.4, have been shown to alleviate some of the problems faced by those suffering from jet lag or the effects of changing shifts. Since the biological clock is controlled by light, exposure to bright light during work shifts and exposure to dim light outside of work can help combat insomnia and symptoms of anxiety and depression (Huang, Tsai, Chen, and Hsu, 2013).

Figure 5.4 Devices like this are designed to be exposed to bright light to help people maintain a regular circadian cycle. They can be useful for people who work night shifts or are affected by seasonal fluctuations in light.

LINK TO LEARN Watch this video ( for tips on overcoming jet lag.

Inadequate Sleep When people have difficulty falling asleep due to work or the demands of daily living, they create a sleep deficit. A person with a chronic sleep deficit does not get enough sleep. Consequences of lack of sleep include reduced alertness and mental performance. curiously since


Chapter 5 | states of consciousness

With the advent of electric light, the amount of sleep people get has decreased. While we certainly appreciate the convenience of having the dark illuminated, we also suffer the consequences of reduced sleep because we are more active than our ancestors during the night. As a result, many of us sleep less than 7-8 hours a night and accumulate sleep debt. While there are huge differences in sleep needs for each person, the National Sleep Foundation (undated) cites research to estimate that newborns need more sleep (between 12 and 18 hours a night) and that amount drops to just 7 to 9 hours a day. the time we are adults decreases. If you lie down for a nap and fall asleep very easily, you probably have sleep debt. Given that college students are notorious for being severely sleep-deprived (Hicks, Fernandez & Pelligrini, 2001; Hicks, Johnson & Pelligrini, 1992; Miller, Shattuck & Matsangas, 2010), it is likely that you and your colleagues who deal with sleep regularly deal with debt problems. In 2015, the National Sleep Foundation updated its sleep durations to better reflect individual differences. Table 5.1 shows the new recommendations, which describe the "recommended", "may be appropriate", and "not recommended" sleep durations. Sleep needs at different ages



may be appropriate

Not recommended

0–3 fun

14-17 hours

11-13 hours 18-19 hours

Less than 11 hours More than 19 hours

4–11 fun

12-15 hours

10-11 hours 16-18 hours

Less than 10 hours More than 18 hours

1-2 years

11-14 hours

9-10 hours 15-16 hours

Less than 9 hours More than 16 hours

3-5 years

10-13 hours

8-9 hours 14 hours

Less than 8 hours More than 14 hours

6-13 years

9-11 hours

7-8 hours 12 hours

Less than 7 hours More than 12 hours

14-17 years old

8-10 hours

7 hours 11 hours

Less than 7 hours More than 11 hours

18-25 years

7-9 hours

6 hours 10-11 hours

Less than 6 hours More than 11 hours

26-64 years old

7-9 hours

6 hours 10 hours

Less than 6 hours More than 10 hours

≥65 years

7-8 hours

5-6 hours 9 hours

Less than 5 hours More than 9 hours

Table 5.1

Sleep deficit and sleep deprivation have significant negative psychological and physiological consequences Figure 5.5. As mentioned earlier, lack of sleep can lead to decreased mental alertness and cognitive function. Furthermore, sleep deprivation often leads to depression-like symptoms. These effects may occur as a result of accumulated sleep deprivation or in response to more acute periods of sleep deprivation. It might surprise you to learn that sleep deprivation is linked to obesity, high blood pressure, and high blood pressure.

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Chapter 5 | states of consciousness


levels of stress hormones and reduced immune function (Banks & Dinges, 2007). A sleep-deprived person will usually fall asleep faster than if they were not sleep-deprived. Some sleep-deprived individuals have difficulty staying awake when they stop moving (eg, sitting down watching TV or driving). Because of this, sleep-deprived people can also put themselves and others at risk by driving cars or operating dangerous machinery. Some research suggests that sleep deprivation impairs cognitive and motor function as much, if not more, than alcohol intoxication (Williamson & Feyer, 2000).

Figure 5.5 This figure illustrates some of the negative consequences of sleep deprivation. While cognitive deficits are the most obvious, many bodily systems are negatively affected by lack of sleep. (Image credit: modification of work by Mikael Häggström)

LINK TO LEARN To assess your own sleep habits, read this article ( on sleep needs.

The amount of sleep we get varies throughout our lives. When we are young, we spend up to 16 hours a day sleeping. The older we get, the less we sleep. In fact, a meta-analysis, a study that combines the results of many related studies conducted over the past decade, shows that at age 65 we sleep on average less than 7 hours a day (Ohayon, Carskadon, Guilleminault & Vitiello, 2004). As the amount of sleep we sleep varies throughout our lives, our sleep debt would likely adjust accordingly.


Chapter 5 | states of consciousness

5.2 Sleep and why we sleep Learning objectives By the end of this section you will be able to: • describe the areas of the brain involved in sleep • understand the hormone secretions related to sleep • describe various theories that aim to explain the function of the sleep we experience About than a third of our life is sleeping. Since the average life expectancy of US citizens is between 73 and 79 years (Singh & Siahpush, 2006), we can expect to spend about 25 years of our lives sleeping. Some animals never sleep (for example, many species of fish and amphibians); other animals can go without sleep for long periods of time without obvious negative consequences (eg dolphins); However, some animals (eg rats) die after two weeks of sleep deprivation (Siegel, 2008). Why do we dedicate so much time to sleep? Is it absolutely necessary that we sleep? This section addresses these questions and examines various explanations for why we sleep.

WHAT IS SLEEP? You read that sleep is characterized by low physical activity and reduced sensory perception. As discussed by Siegel (2008), a definition of sleep should also include mention of the interaction of circadian and homeostatic mechanisms that regulate sleep. Homeostatic regulation of sleep is evidenced by sleep rebound after sleep deprivation. Sleep rebound refers to the fact that a sleep-deprived person tends to take less time to fall asleep on subsequent occasions to sleep. Sleep is characterized by certain patterns of brain activity that can be visualized using electroencephalography (EEG), and different stages of sleep can also be distinguished using EEG (Fig. 5.6).

Figure 5.6 This is a segment of a polysomnogram (PSG), a recording of multiple body variables during sleep. The x-axis shows the passage of time in seconds; This log contains 30 seconds of data. The position of the electrode arrays that produced each signal is marked on the y-axis. The red box includes the EEG output and the waveforms are characteristic of a specific sleep stage. Other curves show other sleep-related data, such as body temperature, muscle activity, and heart rate.

Sleep-wake cycles seem to be controlled by multiple brain areas that work in conjunction with each other. Some of these areas include the thalamus, hypothalamus, and pons. As mentioned earlier, the hypothalamus contains the SCN – the body's biological clock – among other nuclei that work in conjunction with the thalamus to regulate deep sleep. The bridge is important in regulating the rapid eye

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Motion sleep (REM) (National Institutes of Health, n.d.). Sleep is also associated with the secretion and regulation of various hormones from various endocrine glands, including: melatonin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), and growth hormone (National Institutes of Health, n.d.). You read that the pineal gland releases melatonin during sleep (Figure 5.7). Melatonin is believed to be involved in the regulation of various biological rhythms and the immune system (Hardeland et al., 2006). During sleep, the pituitary gland secretes FSH and LH, which are important in regulating the reproductive system (Christensen et al., 2012; Sofikitis et al., 2008). The pituitary gland also secretes growth hormones during sleep, which play a role in physical growth and maturation and other metabolic processes (Bartke, Sun, & Longo, 2013).

Figure 5.7 The pineal and pituitary glands secrete a variety of hormones during sleep.

WHY DO WE SLEEP? Given the central role that sleep plays in our lives and the number of negative consequences associated with sleep deprivation, one would think that we would have a clear understanding of why we sleep. Unfortunately, this is not the case; However, several hypotheses have been proposed to explain the function of sleep.

Adaptive Function of Sleep A popular hypothesis about sleep incorporates the perspective of evolutionary psychology. Evolutionary psychology is a discipline that studies how universal patterns of behavior and cognitive processes evolved over time as a result of natural selection. Variations and adaptations in cognition and behavior make individuals more or less successful in reproducing and passing on their genes to offspring. A hypothesis in this perspective could argue that sleep is essential to recover the resources used during the day. Just as bears hibernate in the winter when resources are scarce, humans can sleep at night to reduce energy consumption. While this is an intuitive explanation of sleep, there is little research to support this explanation. Indeed, it has been suggested that there is no reason to believe that periods of rest and inactivity cannot meet energy needs (Frank, 2006; Rial et al., 2007), and some research has actually found a negative correlation between energy needs and sleep duration (Capellini, Barton, McNamara, Preston, & Nunn, 2008). Another sleep evolutionary hypothesis holds that our sleep patterns evolved as an adaptive response to predatory risks that increase in the dark. Therefore, we sleep in safe areas to reduce the chance of damage. Again, this is an intuitive and compelling explanation of why we sleep. Maybe our ancestors passed


Chapter 5 | states of consciousness

longer periods of sleep to reduce potential predators' attention on themselves. However, comparative research shows that the relationship between predation risk and sleep is very complex and ambiguous. Some research suggests that species at higher risk of predation sleep fewer hours than other species (Capellini et al., 2008), while other researchers suggest that there is no association between the time a given species spends in deep sleep and its risk of predation. (Lesku, Roth, Amlaner & Lima, 2006). It is entirely possible that sleep does not serve a single universal adaptive function and that different species have evolved different sleep patterns in response to their unique evolutionary pressures. While we have discussed the negative consequences of sleep deprivation, it should be noted that there are many benefits associated with adequate sleep. Some of these benefits, listed by the National Sleep Foundation (n.d.), include maintaining a healthy weight, reducing stress levels, improving mood and increasing motor coordination, as well as a host of benefits related to cognition and memory formation. .

Cognitive function of sleep Another theory about why we sleep relates to the importance of sleep for cognitive function and memory formation (Rattenborg, Lesku, Martinez-Gonzalez & Lima, 2007). In fact, we know that sleep deprivation leads to cognitive impairment and memory deficits (Brown, 2012), leading to impairments in our ability to sustain attention, make decisions, and retrieve long-term memories. Furthermore, these deficiencies increase with increasing sleep deprivation (Alhola & Polo-Kantola, 2007). Furthermore, slow sleep after learning a new task can improve resulting performance on that task (Huber, Ghilardi, Massimini, & Tononi, 2004) and appears to be essential for effective memory formation (Stickgold, 2005). Understanding how sleep affects cognitive function should help you understand that studying all night for a test may not be effective and may even be counterproductive.

LINK TO LEARN Watch this short video ( describing sleep deprivation in college students. Here's another short video ( detailing sleep tips for college students.

Sleep has also been linked to other cognitive benefits. Research shows that these potential benefits include increased capacity for creative thinking (Cai, Mednick, Harrison, Kanady & Mednick, 2009; Wagner, Gais, Haider, Verleger & Born, 2004), language learning (Fenn, Nusbaum & Margoliash, 2003 ; Gómez , Bootzin & Nadel, 2006) and inferential judgments (Ellenbogen, Hu, Payne, Titone & Walker, 2007). Certain aspects of sleep may even influence the processing of emotional information (Walker, 2009).

LINK TO LEARN Watch this short video ( that describes the relationship between sleep and memory.

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5.3 Stages of Sleep Learning Objectives By the end of this section, you will be able to: • Distinguish between REM and non-REM sleep • Describe the differences between the four stages of non-REM sleep • Understand the role of REM sleep and non-REM sleep REM sleep Sleep Game in Learning and Memory Sleep is not a uniform state. Rather, sleep consists of several different phases that can be distinguished from one another by the patterns of brain wave activity that occur during each phase. These changes in brain wave activity can be displayed on the EEG and differ in both frequency and amplitude of the brain waves (Fig. 5.8). Sleep can be divided into two different general phases: REM sleep and non-REM sleep (NREM). REM (Rapid Eye Movement) sleep is characterized by sudden eye movements with the eyelids closed. Brain waves during REM sleep appear to be very similar to brain waves during wakefulness. In contrast, non-REM sleep (NREM) is divided into four phases, which differ from each other and from the waking state by characteristic brain wave patterns. The first four stages of sleep are NREM sleep, while the fifth and final stage of sleep is REM sleep. In this section, we'll discuss each of these sleep stages and the brainwave activity patterns associated with them.

Figure 5.8 Brainwave activity changes dramatically at different stages of sleep. (Credit "Sleeping": Modification of work by Ryan Vaarsi)

STAGES OF NREM SLEEP The first phase of NREM sleep is known as stage 1 sleep. Stage 1 sleep is a transition phase between wakefulness and sleep, the moment when we fall asleep. During this period, both the respiratory rate and the heartbeat slow down. Additionally, Stage 1 sleep involves a significant decrease in overall muscle tone and core body temperature. In terms of brainwave activity, stage 1 sleep is associated with alpha and theta waves. The first part of stage 1 sleep produces alpha waves of relatively low frequency (8 to 13 Hz), high amplitude patterns of electrical activity (waves) that become synchronized (Figure 5.9). This pattern of brainwave activity is similar to that of a person who is very relaxed but still awake. As a person goes through stage 1 sleep, theta wave activity increases. Theta waves are an even lower frequency (4-7 Hz), higher amplitude brain waves than alpha waves. It's relatively easy to wake someone offstage.


Chapter 5 | states of consciousness

1 sleep; In fact, when awakened during stage 1 sleep, people often report not having slept at all.

Figure 5.9 Brainwave activity changes dramatically across stages of sleep.

When we move into stage 2 sleep, the body enters a state of deep relaxation. Theta waves still dominate brain activity, but they are punctuated by short bursts of activity known as sleep spindles (Figure 5.10). A sleep spindle is a rapid burst of high-frequency brain waves that may be important for learning and memory (Fogel & Smith, 2011; Poe, Walsh & Bjorness, 2010). In addition, the occurrence of K-complexes is often associated with stage 2 sleep. A K-complex is a very high-amplitude pattern of brain activity that, in some cases, can occur in response to environmental stimuli. Therefore, K-complexes could serve as a bridge to higher levels of arousal in response to what is happening in our environment (Halász, 1993; Steriade & Amzica, 1998).

Figure 5.10 Stage 2 sleep is characterized by the appearance of sleep spindles and K complexes.

Stages 3 and 4 of sleep are often called deep sleep or deep sleep because these stages are characterized by low-frequency (up to 4 Hz) and high-amplitude delta waves (Figure 5.11). During this time, a person's heart rate and breathing slow down dramatically. It's much harder to wake up

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someone awakens during stage 3 and stage 4 than in the previous stages. Interestingly, individuals who have increased alpha brain wave activity during stages 3 and 4 (most commonly associated with alertness and the transition to stage 1 sleep) report not feeling refreshed upon waking, regardless of how long they slept ( Stone, Taylor, McCrae, Kalsekar & Lichtstein, 2008).

Figure 5.11 (a) Delta waves, which are of low frequency and high amplitude, characterize (b) slow waves in stages 3 and 4 of sleep.

REM SLEEP As mentioned earlier, REM sleep is characterized by rapid eye movements. The brain waves associated with this sleep stage are very similar to those observed when a person is awake, as shown in Figure 5.12, and it is in this sleep stage that dreams occur. It is also associated with paralysis of the body's muscular systems, except those that allow circulation and breathing. Therefore, no voluntary muscle movement occurs in a normal individual during REM sleep; Due to this combination of high brain activity and lack of muscle tone, REM sleep is often referred to as paradoxical sleep. Like NREM sleep, REM sleep has been linked to various aspects of learning and memory (Wagner, Gais, & Born, 2001), although there is disagreement within the scientific community as to the importance of both NREM and REM sleep for normal sleep. learning and memory (Siegel, 2001).

Figure 5.12 (a) A period of rapid eye movements is marked by the short red line segment. The brain waves associated with REM sleep, highlighted in the red box in (a), look very similar to those observed during wakefulness (b).

If people are deprived of REM sleep and then sleep undisturbed, they will spend more


Chapter 5 | states of consciousness

Time spent in REM sleep in an apparent attempt to make up for time lost in REM sleep. This is known as REM rebound and suggests that REM sleep is also homeostatically regulated. In addition to the role that REM sleep may play in learning and memory processes, REM sleep may also be involved in emotional processing and regulation. In these cases, REM rebound may actually represent an adaptive response to stress in non-depressed individuals, suppressing the emotional significance of aversive events that occurred while they were awake (Suchecki, Tiba, & Machado, 2012). Although sleep deprivation is generally associated with a range of negative consequences (Brown, 2012), the consequences of REM deprivation appear to be less profound (as discussed in Siegel, 2001). In fact, some have suggested that REM withdrawal may actually be beneficial in certain circumstances. For example, REM sleep deprivation has been shown to improve symptoms in people with major depression, and many effective antidepressants suppress REM sleep (Riemann, Berger, & Volderholzer, 2001; Vogel, 1975). It should be noted that some literature reviews question this finding and suggest that sleep deprivation, not limited to REM sleep, is as effective or more effective in alleviating depressive symptoms in some patients suffering from depression. In either case, it is not fully understood why sleep deprivation improves the mood of some patients (Giedke & Schwärzler, 2002). Recently, however, some have suggested that sleep deprivation may alter emotional processing such that various stimuli are perceived as more positive in nature (Gujar, Yoo, Hu, & Walker, 2011). The following hypnogram (Figure 5.13) shows a person's progression through the stages of sleep.

Figure 5.13 A hypnogram is a diagram of the stages of sleep as they occur during a period of sleep. This hypnogram illustrates how a person goes through the different stages of sleep.

LINK TO LEARN Watch this video ( that describes the different stages of sleep.

Dreams The meaning of dreams varies between cultures and times. By the end of the 19th century

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The German psychiatrist Sigmund Freud believed that dreams represent a way to access the unconscious. Freud thought that by analyzing dreams, people could increase their self-esteem and gain valuable information that would help them deal with the problems they faced in their lives. Freud distinguished between manifest and latent content of dreams. Manifest content is the actual content or plot of a dream. Latent content, on the other hand, refers to the hidden meaning of a dream. For example, if a woman dreams of being chased by a snake, Freud may have argued that this represents a woman's fear of sexual intimacy, with the snake serving as a symbol of a man's penis. Freud was not the only theorist to focus on the content of dreams. The 20th-century Swiss psychiatrist Carl Jung believed that dreams allow us to tap into the collective unconscious. The collective unconscious, as described by Jung, is a theoretical repository of information that he believed was shared by all. According to Jung, certain symbols in dreams reflect universal archetypes with similar meanings for all people, regardless of culture or location. However, sleep and dream researcher Rosalind Cartwright believes that dreams simply reflect life events that are important to the dreamer. Unlike Freud and Jung, Cartwright's ideas about dreaming found empirical support. For example, she and her colleagues published a study in which women who were getting divorced were asked multiple times over a five-month period to report how much they thought of their ex-spouses. The same women were awakened during REM sleep to provide a detailed account of the content of their dreams. There was a significant positive correlation between the degree to which women thought about their ex-spouses during their waking hours and the frequency with which their ex-spouses appeared as figures in their dreams (Cartwright, Agargun, Kirkby, & Friedman, 2006). Recent research (Horikawa, Tamaki, Miyawaki, and Kamitani, 2013) has uncovered new techniques that allow researchers to effectively detect and classify visual images that occur during dreaming, using fMRI for neural measurement of brain activity patterns, paving the way for further research. paving in this area. Recently, neuroscientists have also become interested in why we dream. For example, Hobson (2009) suggests that dreaming may represent a state of protoconsciousness. In other words, dreaming means building a virtual reality in our mind that we can use to help us while we are awake. Among a plethora of neurobiological evidence, John Hobson cites research on lucid dreaming as an opportunity to better understand dreams in general. Lucid dreams are dreams in which certain aspects of the waking state are maintained during a dream state. In a lucid dream, a person becomes aware of the fact that he is dreaming and thus can control the dream content (LaBerge, 1990).

5.4 Sleep problems and disorders Learning objectives At the end of this section, you will be able to: • describe insomnia symptoms and treatments • recognize symptoms of different parasomnias • describe sleep apnea symptoms and treatments • recognize risk factors Associated with Sudden Infant Death Syndrome (SIDS) and Measures to Prevent It • Describe the symptoms and treatments for narcolepsy Many people suffer from insomnia at some point in their lives. Depending on the population studied and the sleep disorder, between 30% and 50% of the population will experience a sleep disorder at some point in their lives (Bixler, Kales, Soldiers, Kaels & Healey, 1979; Hossain & Shapiro, 2002; Ohayon , 1997, 2002; Ohayon & Roth, 2002). This section describes various sleep disorders and some of their treatment options.


Chapter 5 | states of consciousness

INSOMNIA Insomnia, a persistent difficulty falling or staying asleep, is the most common sleep disorder. Individuals with insomnia often experience long delays between going to bed and actually falling asleep. Also, these individuals may wake up several times during the night only to find that they are having trouble falling back asleep. As mentioned earlier, one of the criteria for insomnia is having these symptoms at least three nights a week for at least one month (Roth, 2007). It is not uncommon for people suffering from insomnia to experience an increased level of anxiety due to not being able to fall asleep. This becomes a self-perpetuating cycle, as increased anxiety leads to increased arousal, and higher levels of arousal make the prospect of falling asleep even less likely. Chronic insomnia is almost always associated with fatigue and may be associated with depressive symptoms. There can be many factors that contribute to insomnia, including age, drug use, exercise, mental state and bedtime routines. Not surprisingly, treating insomnia can take a number of different approaches. People suffering from insomnia may want to limit their use of stimulants (such as caffeine) or increase their physical activity during the day. Some people may turn to over-the-counter (OTC) or prescription sleep aids to help them sleep, but this should be done in moderation because many sleep aids are addictive and alter the nature of the sleep cycle, and can increase insomnia over time. Those who continue to experience insomnia, particularly if it affects their quality of life, should seek professional care. Some forms of psychotherapy such as Treatments such as cognitive behavioral therapy can help patients with insomnia. Cognitive-behavioral therapy is a form of psychotherapy that focuses on cognitive processes and problem behaviors. Treatment for insomnia would likely include stress management techniques and changes in problem behaviors that may contribute to insomnia (eg, spending more time awake in bed). Cognitive-behavioral therapy has been shown to be very effective in treating insomnia (Savard, Simard, Ivers, & Morin, 2005; Williams, Roth, Vatthauer, & McCrae, 2013).

Parasomnias A parasomnia belongs to a group of sleep disorders in which unwanted and disturbing motor activities and/or sleep experiences play a role. Parasomnias can occur in REM or NREM sleep phases. Sleepwalking, restless legs syndrome and night terrors are examples of parasomnias (Mahowald & Schenck, 2000).

Sleepwalking In sleepwalking, or somnambulism, the sleeper exhibits relatively complex behaviors ranging from wandering to driving a car. During sleepwalking, sleepers often have their eyes open, but they do not respond to attempts to communicate with them. Sleepwalking is most common during deep sleep, but it can occur in some patients at any time during sleep (Mahowald & Schenck, 2000). Historically, sleepwalking has been treated with a variety of pharmacotherapies, from benzodiazepines to antidepressants. However, the success rate of such treatments is questionable. Guilleminault et al. (2005) found that sleepwalking was not alleviated by the use of benzodiazepines. However, all of his sleepwalking patients who also suffered from sleep-related breathing problems showed a significant decrease in sleepwalking when their breathing problems were effectively treated.

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DIG DEEPER A sleepwalking defense? On January 16, 1997, Scott Falater sat down to dinner with his wife and children and told them about the difficulties he was having with a project at work. After dinner, he prepared some materials for leading a church youth group the next morning, then tried to fix the family pool pump before going to bed. The next morning, he woke up to dogs barking and unfamiliar voices downstairs. When he went to see what was going on, he was greeted by a group of police officers who arrested him for the murder of his wife (Cartwright, 2004; CNN, 1999). Yarmila Falater's body was found in the family pool with 44 stab wounds. A neighbor called the police after seeing Falater standing over his wife's body before dragging her into the pool. During a search of the scene, police found bloodstained clothing and a bloody knife in the trunk of Falater's car, and he had bloodstains on his neck. Notably, Falater insisted that he did not remember hurting his wife in any way. His children and his wife's parents agreed that Falater had an excellent relationship with his wife, and they could think of no reason that would provide any motive for murdering her (Cartwright, 2004). Scott Falater had regular sleepwalking episodes as a child and even once behaved violently towards his sister when she tried to stop him from leaving the house in his pajamas during a sleepwalking episode. He did not suffer from apparent anatomical brain abnormalities or mental disorders. It appeared that Scott Falater had killed his wife in her sleep, or at least that was the defense he used when accused of his wife's murder (Cartwright, 2004; CNN, 1999). In the Falater case, a jury found him guilty of first-degree murder in June 1999 (CNN, 1999); However, there are other murder cases where the sleepwalking defense has been used successfully. As frightening as it sounds, many sleep researchers believe that homicidal sleepwalking is possible in individuals suffering from the types of sleep disorders described below (Broughton et al., 1994; Cartwright, 2004; Mahowald, Schenck & Cramer Bornemann, 2005; Pressman, 2007).

REM sleep behavior disorder (RBD) REM sleep behavior disorder (RBD) occurs when the muscle paralysis associated with the REM sleep phase does not occur. Individuals suffering from RBD engage in high levels of physical activity during REM sleep, particularly during disturbing dreams. These behaviors vary widely, but can include kicking, hitting, scratching, screaming, and acting like a scared or attacked animal. People suffering from this disorder can hurt themselves or their sleep partners if they engage in these behaviors. Furthermore, these behaviors end up interrupting sleep, even if the affected individuals have no recollection of the occurrence of these behaviors (Arnulf, 2012). This disorder is linked to a number of neurodegenerative diseases such as Parkinson's disease. In fact, this relationship is so robust that some see the presence of RBD as a potential aid in the diagnosis and treatment of a variety of neurodegenerative diseases (Ferini-Strambi, 2011). Clonazepam, an anti-anxiety drug with sedative properties, is most commonly used to treat RBD. It is given alone or in conjunction with doses of melatonin (the hormone secreted by the pineal gland). As part of treatment, the sleeping environment is often modified to make it a safer place for patients with RCD (Zangini, Calandra-Buonaura, Grimaldi, & Cortelli, 2011).

Other Parasomnias A person with Restless Legs Syndrome has uncomfortable sensations in the legs during periods of inactivity or when trying to fall asleep. This discomfort is alleviated by conscious movement of the legs, which, unsurprisingly, contributes to difficulty falling or staying asleep. Restless legs syndrome is widespread and has been linked to several other medical diagnoses, such as chronic kidney disease and diabetes (Mahowald & Schenck, 2000). There are a variety of medications used to treat restless legs syndrome:


Chapter 5 | states of consciousness

Benzodiazepines, opiates, and anticonvulsants (Restless Legs Syndrome Foundation, undated). Night terrors make the patient feel panicky and are often accompanied by screaming and attempts to flee the immediate area (Mahowald & Schenck, 2000). Although individuals suffering from night terrors appear to be awake, they often have no recollection of the events that occurred, and attempts to comfort them are ineffective. People who suffer from night terrors usually go back to sleep within a short time. Night terrors seem to occur during the NREM sleep phase (Provini, Tinuper, Bisulli & Lagaresi, 2011). Generally, treatment for night terrors is unnecessary unless there is an underlying medical or psychological condition that contributes to the night terrors (Mayo Clinic, n.d.).

SLEEP APNEA Sleep apnea is defined as episodes in which the sleeper stops breathing. These episodes can last 10 to 20 seconds or longer and are usually associated with brief periods of arousal. Individuals suffering from sleep apnea may not be aware of these repeated sleep disruptions, but they do experience increased levels of fatigue. Many people diagnosed with sleep apnea first seek treatment because their sleep partners report that they snore loudly and/or stop breathing for long periods of time during sleep (Henry & Rosenthal, 2013). Sleep apnea is significantly more common in overweight people and is often associated with loud snoring. Surprisingly, sleep apnea can worsen cardiovascular disease (Sánchez-de-la-Torre, Campos-Rodriguez & Barbé, 2012). While sleep apnea is less common in thin people, anyone, regardless of weight, who snores loudly or gasps in their sleep should be screened for sleep apnea. Although people are often unaware of their sleep apnea, they are aware of some of the adverse effects of insufficient sleep. Imagine a patient who believes that because of his sleep apnea he “had three car accidents in six weeks. They were all my fault. Only later did I learn that he was involved in two of them” (Henry & Rosenthal, 2013, p. 52). It is not uncommon for people with undiagnosed or untreated sleep apnea to worry that their careers will be affected by lack of sleep, illustrated by another patient's statement: "I have a job that makes mental alertness particularly important. I was very sleepy... and having difficulty concentrating... It got to a bit of a scary point" (Henry & Rosenthal, 2013, p. 52). There are two types of sleep apnea: obstructive sleep apnea and central sleep apnea. Obstructive sleep apnea occurs when a person's airways become blocked during sleep, preventing air from entering the lungs. In central sleep apnea, a disruption in the signals sent by the brain that regulate breathing causes periods of interrupted breathing (White, 2005). One of the most common treatments for sleep apnea is the use of a special device while sleeping. A Continuous Positive Airway Pressure (CPAP) machine includes a m mask that fits over the sleeper's nose and mouth, which is connected to a pump that forces air into the person's airway and forces it to remain open, as shown in Figure 5.14. Some newer CPAP masks are smaller and only cover the nose. This treatment option has been shown to be effective in people with mild to severe sleep apnea (McDaid et al., 2009). However, alternative treatment options are being explored as consistent adherence by CPAP machine users is an issue. Recently, a new EPAP (Expiratory Positive Air Pressure) device has shown promise as an alternative in double-blind trials (Berry, Kryger & Massie, 2011).

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Figure 5.14 (a) A typical CPAP device used to treat sleep apnea is (b) attached to the head with loops and a mask covering the nose and mouth.

SIDS In sudden infant death syndrome (SIDS), a child stops breathing while sleeping and dies. Babies younger than 12 months appear to be at greater risk of SIDS, and boys are at greater risk than girls. Several risk factors have been associated with SIDS, including prematurity, domestic smoking and hyperthermia. There may also be differences in both brain structure and function in infants who die from SIDS (Berkowitz, 2012; Mage & Donner, 2006; Thach, 2005). Extensive research on SIDS has resulted in a series of recommendations for parents to protect their children (Figure 5.15). On the one hand, research suggests that babies should be placed on their backs to sleep and their cribs should not contain items that pose a choking hazard, such as blankets, pillows or quilted pads (pillows that cover the rails of a crib). 🇧🇷 Babies should not wear hats when lying down to avoid overheating, and those living in the child's home should avoid smoking in the home. Recommendations such as these have helped reduce infant mortality from SIDS in recent years (Mitchell, 2009; Task Force on Sudden Infant Death Syndrome, 2011).

Figure 5.15 The Safe to Sleep campaign educates the public on how to minimize risk factors associated with SIDS. This campaign is sponsored in part by the National Institute of Child Health and Human Development.

NARCOLEPSY Unlike the other sleep disorders described in this section, a person with narcolepsy cannot resist falling asleep at inconvenient times. These sleep episodes are often associated with cataplexy, which is a lack of muscle tone or muscle weakness, and in some cases involves complete paralysis of voluntary muscles. This is similar to the type of paralysis that healthy individuals experience during REM sleep (Burgess & Scammell, 2012; Hishikawa & Shimizu, 1995; Luppi et al., 2011). Narcoleptic episodes take on other features of REM sleep. For example, about one-third of people diagnosed with narcolepsy experience vivid, dream-like hallucinations during narcoleptic attacks (Chokroverty, 2010). Surprisingly, narcoleptic episodes are often triggered by states of heightened arousal or stress. The typical episode can last from one or two minutes to half an hour. After waking up from a narcoleptic attack, people report feeling refreshed (Chokroverty, 2010). Of course, regular narcoleptic episodes can impair the ability to do work or school, and in some situations narcolepsy can result.


Chapter 5 | states of consciousness

result in significant damage and injury (for example, driving or operating machinery or other potentially dangerous equipment). Generally, narcolepsy is treated with psychomotor stimulants such as amphetamines (Mignot, 2012). These drugs promote increased neural activity. Narcolepsy is associated with reduced levels of the hypocretin signaling molecule in some areas of the brain (De la Herrán-Arita & Drucker-Colín, 2012; Han, 2012), and traditional stimulants do not directly affect this system. Therefore, it is very likely that new drugs under development for the treatment of narcolepsy will target the hypocretin system. There is enormous variability among patients, both in how the symptoms of narcolepsy manifest themselves and in the effectiveness of currently available treatment options. This is illustrated by McCarty's (2010) case study of a 50-year-old woman who sought help for several years of excessive sleepiness during normal waking hours. She reported falling asleep at inappropriate or dangerous times, including while eating, hanging out with friends, and driving. During phases of emotional arousal, the woman complained of a certain weakness on the right side of her body. Although she did not experience dream-like hallucinations, she was diagnosed with narcolepsy based on sleep tests. In her case, the fact that her cataplexy was confined to the right side of her body was quite unusual. Early attempts to treat her condition with a stimulant alone were unsuccessful. However, when a stimulant was taken along with a popular antidepressant, her condition dramatically improved.

5.5 Substance Use and Abuse Learning Objectives By the end of this section, you will be able to: • describe the diagnostic criteria for substance use disorders • identify the neurotransmitter systems that are affected by different categories of drugs • describe how different categories of Drugs Affect Behavior and Experience We all regularly experience altered states of consciousness in the form of sleep, some people use drugs and other substances that also cause altered states of consciousness. This section contains information about the use of various psychoactive drugs and problems associated with their use. This is followed by brief descriptions of the effects of some of the best known drugs in common use today.

SUBSTANCE USE DISORDERS The Fifth Edition of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) is used by physicians to diagnose individuals who suffer from various mental disorders. Substance use disorders are addictive disorders, and criteria for specific substance (drug) use disorders are described in the DSM-5. A person suffering from a substance use disorder often uses more of the substance than they originally intended and continues to use that substance despite having significant adverse consequences. In individuals diagnosed with a substance use disorder, there is a compulsive pattern of drug use often associated with physical and psychological dependence. Physical dependence involves changes in normal bodily functions - the user will experience withdrawal from the drug after stopping use. In contrast, a person with psychological dependence has an emotional rather than a physical need for the drug and may use the drug to relieve psychological stress. Tolerance is associated with physiological dependence and occurs when a person requires increasing amounts of medication to achieve effects previously experienced at lower doses. Tolerance can cause the user to increase this

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Amount of drug consumed to a dangerous level - to the point of overdose and death. Drug withdrawal encompasses a range of negative symptoms that occur when drug use is stopped. These symptoms are often the opposite of the drug's effects. For example, withdrawal from sedatives often leads to uncomfortable excitement and excitement. In addition to withdrawal, many individuals diagnosed with substance use disorders also develop tolerance to these substances. Psychological dependency or drug dependence is a new addition to the diagnostic criteria for substance use disorders in the DSM-5. This is an important factor as we can develop tolerance and withdrawal from any number of drugs that we do not abuse. In other words, physical dependence itself is of limited use in determining whether or not someone has a substance use disorder.

DRUG CATEGORIES All psychoactive drugs work through their interactions with our endogenous neurotransmitter systems. Many of these drugs and their relationships are shown in Figure 5.16. As you've learned, drugs can act as agonists or antagonists to a particular neurotransmitter system. An agonist facilitates the activity of a neurotransmitter system and antagonists prevent the activity of the neurotransmitter.

Figure 5.16 This figure illustrates different drug categories and their overlap. (Credit: Modification of work by Derrick Snider)

Alcohol and other depressants Ethanol, which we commonly refer to as alcohol, belongs to a class of psychoactive drugs known as depressants.


Chapter 5 | states of consciousness

(Figure 5.17). A sedative is a drug that tends to suppress central nervous system activity. Other tranquilizers include barbiturates and benzodiazepines. What these drugs have in common is that they can act as agonists of the gamma-aminobutyric acid (GABA) neurotransmitter system. Since GABA has a calming effect on the brain, GABA agonists also have a calming effect; These types of medications are often prescribed to treat anxiety and insomnia.

Figure 5.17 The GABA-gated chloride (Cl-) channel is embedded in the cell membrane of certain neurons. The channel has several receptor sites where alcohol, barbiturates, and benzodiazepines bind to exert their effects. The binding of these molecules opens the chloride channel, allowing negatively charged chloride ions (Cl-) to enter the cell body of the neuron. Shifting its charge to a negative direction pulls the neuron away from firing; Therefore, activating a GABA neuron has a calming effect on the brain.

Acute alcohol administration leads to a variety of changes in consciousness. At very low doses, alcohol consumption is associated with feelings of euphoria. As the dose increases, people report feeling sedated. In general, alcohol is associated with a decrease in reaction time and visual acuity, reduced alertness, and reduced behavioral control. With excessive alcohol consumption, a person may experience a complete loss of consciousness and/or have difficulty remembering events that occurred while intoxicated (McKim & Hancock, 2013). Furthermore, if a pregnant woman consumes alcohol, her child may be born with a cluster of birth defects and symptoms collectively known as fetal alcohol spectrum disorder (FASD) or fetal alcohol syndrome (FAS). With repeated use of many central nervous system depressants, such as alcohol, the person becomes physically dependent on the substance and shows signs of tolerance and withdrawal. Psychological dependence on these drugs is also possible. Therefore, the abuse potential of CNS depressants is relatively high. Drug withdrawal is often an aversive experience and can be a life-threatening process in individuals with a long history of using very high doses of alcohol and/or barbiturates. This is so concerning that people trying to break addiction to these substances should only do so under medical supervision.

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Stimulants Stimulants are drugs that tend to increase the general level of neural activity. Many of these drugs act as agonists on the dopamine neurotransmitter system. Dopamine activity is often associated with reward and desire; Therefore, drugs that affect dopamine neurotransmission are often subject to abuse. Drugs in this category include cocaine, amphetamines (including methamphetamines), cathinones (ie bath salts), MDMA (ecstasy), nicotine and caffeine. Cocaine can be ingested in several ways. Although many users snort cocaine, intravenous injection and ingestion are also common. The freebase version of cocaine, known as crack, is a strong, smokeable version of the drug. Like many other stimulants, cocaine tortures the dopaminergic neurotransmitter system by blocking the reuptake of dopamine at the neuronal synapse.

GO FURTHER Crack Cocaine Crack (Figure 5.18) is often considered more addictive than cocaine itself because it can be smoked and reaches the brain very quickly. Crack is often cheaper than other forms of cocaine; As such, it tends to be a more accessible drug for individuals from impoverished sectors of society. In the 1980s, many drug laws were rewritten to penalize crack users more severely than cocaine users. This resulted in discriminatory sentences, with low-income inner-city minorities receiving the harshest sentences. The wisdom of these laws has recently been questioned, particularly in light of research suggesting that crack may not be more addictive than other forms of cocaine, as previously thought (Haasen & Krausz, 2001; Reinerman, 2007).

Figure 5.18 Crack rocks like this are smoked to get high. Compared to other routes of administration, smoking a drug can reach the brain more quickly, which can often improve the user experience. (Credit: US Department of Justice Work Amendment)

LINK TO LEARN Read this interesting newspaper article ( that details the myths about crack.

Amphetamines have a very similar mechanism of action to cocaine in that they block the reuptake of dopamine and, in addition, stimulate its release (Figure 5.19). Although amphetamines are often abused, they are also commonly prescribed to children who have been diagnosed with Attention Deficit Hyperactivity Disorder (ADHD).


Chapter 5 | states of consciousness

It may seem counterintuitive that stimulants are prescribed to treat a disorder associated with hyperactivity, but the therapeutic effect comes from an increase in neurotransmitter activity in specific areas of the brain associated with impulse control.

Fig. 5.19 As one of their mechanisms of action, cocaine and amphetamines block the reuptake of dopamine from the synapse into the presynaptic cell.

In recent years, methamphetamine (methamphetamine) use has become more widespread. Methamphetamine is a type of amphetamine that can be made from readily available ingredients (such as drugs that contain pseudoephedrine, a compound found in many over-the-counter cold and flu remedies). Despite recent legislative changes designed to make pseudoephedrine more difficult to obtain, methamphetamine remains an easily accessible and relatively inexpensive drug option (Shukla, Crump, and Chrisco, 2012). Users of cocaine, amphetamines, cathinones and MDMA seek euphoria, feelings of intense euphoria and joy, especially in users who inject or smoke the drug intravenously. Repeated use of these stimulants can have significant adverse consequences. Users may experience physical symptoms such as nausea, increased blood pressure and increased heart rate. Furthermore, these drugs can cause anxiety, hallucinations and paranoia (Fiorentini et al., 2011). Normal brain function is altered after repeated use of these drugs. For example, repeated use can lead to a general depletion of monoamine neurotransmitters (dopamine, norepinephrine, and serotonin). People may compulsively use these stimulating substances, in part to try to restore normal levels of these neurotransmitters (Jayanthi & Ramamoorthy, 2005; Rothman, Blough, & Baumann, 2007). Caffeine is another stimulant. Although it is probably the most widely used drug in the world, the potency of this particular drug is negligible compared to the other stimulants discussed in this section. In general, people use caffeine to maintain high levels of alertness and arousal. Caffeine is found in many common pharmaceuticals (e.g., weight loss medications), beverages, foods, and even cosmetics (Herman & Herman, 2013). Although caffeine may have some indirect effects on dopamine neurotransmission, its main mechanism of action involves antagonism of adenosine activity (Porkka-Heiskanen, 2011).

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Although caffeine is generally considered a relatively safe drug, high levels of caffeine in the blood can cause insomnia, restlessness, muscle spasms, nausea, irregular heartbeat, and even death (Reissig, Strain, and Griffiths, 2009; Wolt, Ganetsky, and Babu, 2012). 🇧🇷 In 2012, Kromann and Nielson reported a case study of a 40-year-old woman who was experiencing significant adverse effects from her caffeine consumption. The woman historically used caffeine to improve her mood and provide energy, but over the course of several years, she increased her caffeine intake to the point of consuming three liters of soda a day. Despite taking a prescribed antidepressant, her depression symptoms continued to worsen and she began to suffer physically, showing clear signs of cardiovascular disease and diabetes. Upon admission to an outpatient clinic for treatment of mood disorders, she met all diagnostic criteria for substance dependence and was advised to drastically limit her caffeine intake. Once she was able to limit her consumption to less than 12 ounces of soda a day, her mental and physical health gradually improved. Despite the prevalence of caffeine use and the large number of people professing to suffer from caffeine dependence, this was the first published description of soda dependence to appear in the scientific literature. Nicotine is highly addictive and the use of tobacco products is associated with an increased risk of heart disease, stroke and a variety of cancers. Nicotine exerts its effects through its interaction with acetylcholine receptors. Acetylcholine functions as a neurotransmitter in motor neurons. In the central nervous system, it plays a role in arousal and reward mechanisms. Nicotine is most commonly used in the form of tobacco products such as cigarettes or chewing tobacco; Therefore, there is a great deal of interest in developing effective techniques for quitting smoking. To date, people have used a variety of nicotine replacement therapies, as well as various psychotherapeutic options for stopping the use of tobacco products. In general, smoking cessation programs can be effective in the short term, but it is unclear whether these effects last (Cropley, Theadom, Pravettoni, & Webb, 2008; Levitt, Shaw, Wong, & Kaczorowski, 2007; Smedslund, Fisher , Boles , & Liechtenstein, 2004).

Opioids An opioid belongs to a category of drugs that includes heroin, morphine, methadone, and codeine. Opioids have analgesic properties; that is, they reduce pain. Humans have an endogenous opioid neurotransmitter system – the body produces small amounts of opioid compounds that bind to opioid receptors, relieving pain and inducing euphoria. Therefore, opioid drugs that mimic this endogenous analgesia mechanism have an extremely high potential for abuse. Natural opioids, called opiates, are derived from opium, a natural compound found in the poppy plant. There are now several synthetic versions of opiates (properly called opiates) that have very powerful analgesic effects, and are often abused. For example, the National Institutes on Drug Abuse has sponsored research suggesting that misuse and abuse of the prescription pain relievers hydrocodone and oxycodone is a significant public health problem (Maxwell, 2006). In 2013, the U.S. Tighter Food and Drug Administration controls over its medicinal uses. Historically, heroin has been one of the main opioids of abuse (Figure 5.20). Heroin can be snorted, smoked, or injected intravenously. Like the stimulants described above, heroin use is associated with an initial feeling of euphoria, followed by periods of excitement. Because heroin is often given by intravenous injection, users often have needle marks on their arms and, like all injecting drug users, are at increased risk of contracting tuberculosis and HIV.


Chapter 5 | states of consciousness

Figure 5.20 (a) Utensils commonly used in the preparation and use of heroin are shown here in a needle exchange kit. (b) Heroin is cooked in a spoon over a candle. (Credit to: Modification of work by Todd Huffman)

In addition to their usefulness as analgesics, opioid-type compounds are commonly found in cough suppressants, anti-nausea, and diarrhea medications. Given that drug withdrawal often involves experiencing the opposite of drug effects, it should come as no surprise that opioid withdrawal feels like a bad case of the flu. Although opioid withdrawal can be extremely uncomfortable, it is not life threatening (Julien, 2005). However, people suffering from opioid withdrawal may be given methadone to make withdrawal from the drug less difficult. Methadone is a synthetic opioid that is less euphoric than heroin and similar drugs. Methadone clinics help people who have previously struggled with opioid addiction to manage methadone withdrawal symptoms. Other medications, including the opioid buprenorphine, have also been used to relieve opiate withdrawal symptoms. Codeine is a relatively low potency opioid. It is often prescribed for mild pain and is available over the counter in some other countries. Like all opioids, codeine has potential for abuse. Indeed, prescription opioid medication abuse is becoming a major problem worldwide (Aquina, Marques-Baptista, Bridgeman, and Merlin, 2009; Casati, Sedefov, and Pfeiffer-Gerschel, 2012).

Hallucinogens A hallucinogen belongs to a class of drugs that produce profound changes in sensory and perceptual experiences (Figure 5.21). In some cases, users experience vivid visual hallucinations. It is also common for these types of drugs to cause hallucinations of bodily sensations (for example, feeling like a giant) and a distorted perception of the passage of time.

Figure 5.21 Psychedelic images like this are often associated with hallucinogenic compounds. (Credit: Work modification by "new 1lluminati"/Flickr)

As a group, hallucinogens are incredibly diverse in terms of the neurotransmitter systems they affect. Mescaline and LSD are serotonin agonists, and PCP (angel dust) and ketamine (animal anesthetic) act as NMDA glutamate receptor antagonists. It is generally believed that these drugs do not have the same abuse potential as other classes of drugs discussed in this section.

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LINK TO LEARN To learn more about some of the most common prescription and abused drugs, see the Table of Commonly Abused Drugs ( and the Table of Commonly Abused Prescription Drugs ( and the Table of Commonly Abused Prescription Drugs ( /openstax .org/l/Rxabuse) from the National Institute on Drug Abuse.

DURING FURTHER Medical Marijuana While the possession and use of marijuana is illegal in most states, it is now legal in Washington and Colorado to possess limited amounts of recreational marijuana (Figure 5.22). In contrast, medical marijuana use is now legal in nearly half of the United States and the District of Columbia. Medical marijuana is marijuana that is prescribed by a doctor to treat a health condition. For example, people undergoing chemotherapy are often given marijuana to stimulate their appetite and prevent excessive weight loss due to side effects of chemotherapy treatment. Marijuana may also show promise in treating a variety of conditions (Mather, Rauwendaal, Moxham-Hall, and Wodak, 2013; Robson, 2014; Schicho and Storr, 2014).

Figure 5.22 Medical marijuana stores are becoming more common in the United States. (Image credit: Laurie Avocado) Although medical marijuana laws have been passed state by state, federal laws still classify it as an illegal substance, making conducting research into the potentially beneficial medicinal uses of marijuana problematic. There is some controversy in the scientific community about the extent to which marijuana may have medicinal benefits due to the lack of large-scale controlled research (Bostwick, 2012). As a result, many scholars have urged the federal government to allow current marijuana laws and classifications to be relaxed to allow for a more comprehensive study of the drug's effects (Aggarwal et al., 2009; Bostwick, 2012; Kogan & Mechoulam, 2007). . Until recently, the US Department of Justice routinely arrested participants and seized marijuana used in medical facilities. However, in the fall of 2013, the US Department of Justice issued statements indicating that it would no longer challenge state medical marijuana laws. This policy change may be a response to recommendations from the scientific community and/or reflect changing public opinion on marijuana.



Chapter 5 | states of consciousness

5.6 Learning Objectives for Other States of Consciousness By the end of this section, you will be able to: • define hypnosis and meditation • understand the similarities and differences between hypnosis and meditation Our states of consciousness change as we transition from wakefulness to sleep . We also alter our consciousness through the use of various psychoactive drugs. In this final section, hypnotic and meditative states are considered as additional examples of altered states of consciousness experienced by some individuals.

HYPNOSIS Hypnosis is a state of extreme self-focus and attention in which minimal attention is paid to external stimuli. In the therapeutic setting, a clinician can use relaxation and suggestion to try to change a patient's thoughts and perceptions. Hypnosis has also been used to extract information believed to be deeply buried in a person's memory. For individuals who are particularly open to the power of suggestion, hypnosis can be a very effective technique, and brain imaging studies have shown that hypnotic states are associated with global changes in brain function (Del Casale et al., 2012; Guldenmund, Vanhaudenhuyse, Boly , Laureys & Soddu, 2012). In the past, hypnosis was viewed with some suspicion because of its portrayal in popular media and entertainment (Figure 5.23). It is therefore important to distinguish between hypnosis as an empirically based therapeutic approach and as a form of entertainment. Contrary to popular belief, people who undergo hypnosis often have clear memories of the hypnotic experience and are in control of their own behavior. While hypnosis can be useful for improving memory or a skill, these improvements are inherently very modest (Raz, 2011).

Figure 5.23 Popular accounts of hypnosis have led to some common misconceptions.

How exactly does a hypnotist bring a participant into a state of hypnosis? While there are variations, there are four parts that seem consistent in bringing people into the state of suggestibility associated with hypnosis (National Research Council, 1994). These components include:

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• The participant is told to concentrate on one thing, such as the hypnotist's words or the ticking of a clock. • The participant is put at ease and instructed to be relaxed and sleepy. • The participant is asked to be open to the hypnosis process, to trust the hypnotist and to let go. • The participant is encouraged to use their imagination.

These steps lead to being open to the increased suggestibility of hypnosis. People vary in their ability to be hypnotized, but a review of available research suggests that most people are at least moderately hypnotizable (Kihlstrom, 2013). Hypnosis, in conjunction with other techniques, is used for a variety of therapeutic purposes and has been shown to be at least somewhat effective in controlling pain, managing depression and anxiety, smoking cessation, and weight loss (Alladin, 2012; Elkins, Johnson, & Fisher, 2012; Golden, 2012; Montgomery, Cord, & Kravits, 2012). Some researchers are working to determine whether the power of suggestion can affect cognitive processes such as learning to use hypnosis in educational settings (Wark, 2011). In addition, there is evidence that hypnosis can alter processes previously considered automatic and beyond the reach of voluntary control, such as: B. reading (Lifshitz, Aubert Bonn, Fischer, Kashem, & Raz, 2013; Raz, Shapiro, Fan, & Poner, 2002). However, it should be noted that others have suggested that the automatism of these processes remains intact (Augustinova & Ferrand, 2012). How does hypnosis work? Two theories try to answer this question: one theory sees hypnosis as dissociation and the other as social role awareness. From a dissociation point of view, hypnosis is effectively a dissociated state of consciousness, similar to our earlier example where you may be driving to work but are minimally aware of the act of driving because your attention is elsewhere. This theory is supported by Ernest Hilgard's research on hypnosis and pain. In Hilgard's experiments, he put participants in a state of hypnosis and immersed their arms in ice water. Participants were told that they would not feel pain, but could push a button if they did; Although they did not report pain, they did press the button, suggesting a dissociation of consciousness during the hypnotic state (Hilgard & Hilgard, 1994). Sociocognitive theory of hypnosis takes a different approach to explaining hypnosis and sees people in hypnotic states fulfilling the social role of a hypnotized person. As you will learn as you study social roles, people's behavior can be shaped by their expectations of how they should behave in a given situation. Some see a hypnotized person's behavior not as an altered or dissociated state of consciousness, but as a fulfillment of social expectations for that role.

MEDITATION Meditation is the act of focusing on a single target (such as the breath or a repeated sound) to increase awareness of the moment. While hypnosis is usually achieved through the interaction of a therapist and the person being treated, a person can meditate on their own. However, people who want to learn to meditate are often trained in techniques for achieving a meditative state. A meditative state, as the EEG recordings of new practitioners show, is not an altered state of consciousness per se; however, brain wave patterns displayed by experienced meditators may represent a unique state of consciousness (Fell, Axmacher, & Haupt, 2010). Although several different techniques are used, the core feature of any meditation is clearing the mind to achieve a state of relaxed mindfulness and focus (Chen et al., 2013; Lang et al., 2012). Mindfulness meditation has recently become popular. Variations on meditation focus the meditator's attention on an internal process or external object (Zeidan, Grant, Brown, McHaffie, & Coghill, 2012). Meditative techniques have their roots in religious practices (Fig. 5.24), but their use is gaining popularity among practitioners of alternative medicine. Research suggests that meditation can help lower blood pressure, and the American Heart Association suggests that meditation can be used


Chapter 5 | states of consciousness

Association with more traditional treatments as a way to treat hypertension, although there is not enough data to make a recommendation (Brook et al., 2013). Like hypnosis, meditation shows promise in managing stress, improving sleep (Caldwell, Harrison, Adams, Quin & Greeson, 2010), treating mood and anxiety disorders (Chen et al., 2013; Freeman et al. , 2010; Vøllestad, Nielsen & Nielsen, 2012) and pain control (Reiner, Tibi & Lipsitz, 2013).

Figure 5.24 (a) This is a statue of a meditating Buddha, representing one of the many religious traditions in which meditation plays a role. (b) People who practice meditation may experience a different state of consciousness. (credit a: modification of work by Jim Epler; credit b: modification of work by Caleb Roenigk)

LINK TO LEARN Feeling stressed? Do you think meditation can help? This instructional video ( teaches you how to use Buddhist meditation techniques to reduce stress.

LINK TO LEARN Watch this video ( which describes the results of a brain imaging study on people who underwent certain meditative mindfulness techniques.

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Key Terms Alpha wave A type of brain wave of relatively low frequency and relatively high amplitude that is synchronized; characteristic of sleep onset stage 1 biological rhythm internal circuitry of biological activity cataplexy lack of muscle tone or muscle weakness, in some cases complete paralysis of voluntary muscles central sleep apnea sleep disorder with intermittent interruption of breathing due to disturbances in signals sent by the brain that regulate breathing circadian rhythm biological rhythm lasting about 24 hours relatively low potency codeinopiate commonly prescribed for mild pain cognitive behavioral therapy psychotherapy focusing on cognitive processes and problem behaviors sometimes used to treat sleep disorders such as insomnia collective unconscious theoretical archive of information, shared by all people in all cultures, as described by Carl Jung Awareness Awareness of internal and external stimuli CPAP (Continuous Positive Airway Pressure) machine to treat sleep apnea; includes a mask that fits over the sleeper's nose and mouth, which is connected to a pump that pumps air into the person's airways, forcing them to remain open Sedative drug that tends to suppress central nervous system activity euphoria intense feeling of euphoria and intense joy drug use Evolutionary psychological discipline that studies how universal patterns of behavior and cognitive processes have evolved over time as a result of natural selection Hallucinogens A class of drugs that produce profound changes in sensory and perceptual experiences, often with vivid hallucinations Homeostasis Tendency to maintain an optimal balance or level within a biological system Hypnosis State of extreme self-focus and attention in which minimal attention is paid to external stimuli Insomnia Persistent difficulty getting in or out D sleeping at least three nights a week for a month jet lag collection of symptoms caused by traveling one time difference to another resulting from the discrepancy between our internal circadian cycles and the latent content of our environment in response to environmental stimuli hidden meaning of a According to Sigmund Freud on the function of dreams, lucid dreamers become aware that they are dreaming and can control the content of the dream


Chapter 5 | states of consciousness

Manifest the content of the plot of events that occur during a dream, according to Sigmund Freud's view of the function of dreams, meditation to clear the mind to reach a state of relaxed attention and focus meta-analysis of the sleep-wake cycle- Study combining results from several related studies Synthetic methadone opioid less euphoric than heroin and similar drugs; used to treat withdrawal symptoms in opiate users Methadone The Clinic uses methadone to treat withdrawal symptoms in opiate users Methamphetamine Type of amphetamine that can be made from pseudoephedrine, an over-the-counter drug; widespread and abused narcolepsy sleep disorder in which the patient cannot resist falling asleep at inappropriate times sleep disturbance outside of REM (rapid eye movement) sleep obstructive sleep apnea sleep disorder defined by episodes in which breathing during sleep is caused by an obstruction of the airways exposes opiates / opioid belongs to a category of drugs with strong analgesic properties; Opiates are made from the resin of the opium poppy; includes heroin, morphine, methadone, and codeine Pineal gland endocrine structure within the brain that releases melatonin dependence psychological more emotional than physical need for a drug that can be used to relieve psychological stress REM (rapid eye movement) sleep period of sleep caused by brain waves that are very similar to those during wakefulness and by fluttering eye movements with closed eyelids REM sleep behavior disorder (RBD) A sleep disorder in which the muscle paralysis associated with the REM sleep phase does not occur; Sleepers have high levels of physical activity during REM sleep, especially during disturbing dreams. Restless Legs Syndrome Sleep disorder in which the patient has uncomfortable sensations in the legs when trying to fall asleep, which is relieved by moving the legs early to late daily or weekly Sleep condition characterized by relatively little physical activity and reduced sensory perception characterized and distinct from periods of rest that occur during wakefulness

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Sleep apnea A sleep disorder defined by episodes in which breathing stops during sleep Sleep debt A consequence of chronic sleep deprivation Sleep rebound Individuals with sleep deprivation experience shorter sleep latencies during subsequent opportunities for sleep regulation and sleep control brain about switching between sleep and wakefulness and coordinating this cycle with the outside world sleep spindle rapid burst of high-frequency brain waves during stage 2 sleep, which can be important for learning and memory sleepwalking (also known as sleepwalking) such as sleepwalking) sleep disorder in which the sleeper exhibits relatively complex behaviors stage 1 sleep stage 1 sleep; transition phase between wakefulness and sleep; the period during which a person enters sleep stage 2, sleep stage, sleep stage 2; the body goes into deep relaxation; characterized by the appearance of sleep spindles stage 3 sleep stage 3 sleep; deep sleep characterized by low-frequency, high-amplitude delta waves stage 4 sleep stage 4 sleep; Deep sleep, characterized by low-frequency, high-amplitude delta waves, a stimulant drug that tends to increase the overall level of neural activity; includes caffeine, nicotine, amphetamines, and cocaine Sudden Infant Death Syndrome (SIDS) Infant (one year of age or younger) with no apparent illness dies suddenly in sleep Suprachiasmatic Nucleus (SCN) Area of ​​the hypothalamus that houses the body's biological clock Theta - Low-frequency, high-amplitude wave-like brain wave characteristic for the stage 1 and 2 sleep-tolerance condition, requiring increasing amounts of the drug to produce the desired effect of the negative symptoms that occur when drug use is discontinued

Summary 5.1 What is conscience? States of consciousness change throughout the day and throughout our lives. Important factors in these changes are the biological rhythms and, in particular, the circadian rhythms generated by the suprachiasmatic nucleus (SCN). Normally, our body clocks are in line with our external environment, and light is often an important cue for adjusting that clock. When people travel across multiple time zones or work rotating shifts, they can experience disruptions to their circadian cycle, which can lead to insomnia, drowsiness, and decreased alertness. Light therapy has shown promise in treating circadian disorders. Going without sleep for extended periods of time creates a sleep debt and potentially a host of adverse psychological and physiological consequences.


Chapter 5 | states of consciousness

5.2 Sleep and why we sleep We dedicate a large part of our time to sleep, and our brain has complex systems that control various aspects of sleep. During sleep, several important hormones for growth and physical maturation are released. Although the reason why we sleep remains a mystery, there is some evidence that sleep is very important for learning and memory. 5.3 Stages of sleep The different stages of sleep are characterized by the brain wave patterns associated with each stage. When a person transitions from being awake to falling asleep, alpha waves are replaced by theta waves. Sleep spindles and K-complexes arise during stage 2 sleep. Stages 3 and 4 are described as slow wave sleep characterized by a predominance of delta waves. REM sleep involves rapid eye movements, paralysis of voluntary muscles and dreaming. Both NREM and REM sleep appear to play important roles in learning and memory. Dreams can represent life events that are important to the dreamer. Alternatively, dreaming may represent a state of proto-consciousness or a virtual reality in the mind that helps a person while he is conscious. 5.4 Sleep Problems and Disturbances Many people experience some type of sleep disorder or disturbance at some point in their lives. Insomnia is a common experience where people have difficulty falling asleep or staying asleep. Parasomnias involve unwanted motor behaviors or experiences throughout the sleep cycle and include RBD, sleepwalking, restless legs syndrome, and night terrors. Sleep apnea occurs when people stop breathing in their sleep, and in the case of cot death, babies stop breathing in their sleep and die. Narcolepsy involves an overwhelming desire to fall asleep during waking hours and is often associated with cataplexy and hallucinations. 5.5 Substance Use and Abuse A substance use disorder is defined in the DSM-5 as a compulsive pattern of drug use despite adverse outcomes. Both physical and psychological dependence are important components of this disorder. Alcohol, barbiturates, and benzodiazepines are central nervous system depressants that affect GABA neurotransmission. Cocaine, amphetamine, cathinones and MDMA are all central nervous system stimulants that agonize dopamine neurotransmission, while nicotine and caffeine affect acetylcholine and adenosine, respectively. Opiates act as potent analgesics through their effects on the endogenous opioid neurotransmitter system, and hallucinogenic drugs cause marked alterations in sensory and perceptual experiences. Hallucinogens vary in terms of the specific neurotransmitter systems they affect. 5.6 Other States of Consciousness Hypnosis is a focus on the self that involves suggested behavioral and experiential changes. Meditation involves relaxed but focused awareness. Both hypnotic and meditative states can involve altered states of consciousness, which have potential application for treating a variety of physical and mental disorders.

Knowledge review 1. The body's biological clock is on ________. one. hippocampus b. thalamus c. hypothalamus D. pituitary

2. ________ occurs with chronic sleep deprivation. one. jet lag b. work shift change c. circadian rhythm d. sleep debt

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3. ________ cycles occur approximately every 24 hours. one. biological b. circadian c. deliberately turning D.

10. Sleep spindles and K-complexes are most commonly associated with ________ sleep. one. Phase 1b. Stage 2 c. Phase 3 and Phase 4 d. WITHOUT

4. ________ is one way people can help reset their body clock. one. light-dark exposure b. coffee consumption c. alcohol consumption D. siesta

11. ________ symptoms may improve with REM withdrawal. one. schizophrenia b. Parkinson's disease c. depression D. generalized anxiety disorder

5. Growth hormone is secreted by the ________ while we sleep. one. pineal b. thyroid c. pituitary D. pancreas

12. The ________ content of a dream is related to the true meaning of the dream. one. latent b. manifest c. collective unconscious d. important

6. The ________ plays a role in controlling slow-wave sleep. one. hypothalamus b. thalamus c. Pons d. Not just A but also B

13. ________ is a loss of muscle tone or muscle control often associated with narcolepsy. one. hydrographic district b. CPAP c. cataplexy d. insomnia

7. ________ is a hormone secreted by the pineal gland that plays a role in regulating biological rhythm and immune function. one. growth hormone B. melatonin c. LH d. FSH

14. A person can have ________ if there is a disturbance in the brain signals sent to the muscles that regulate breathing. one. central sleep apnea b. obstructive sleep apnea c. narcolepsy D. SIDS

8. ________ appears to be particularly important for improving performance on newly learned tasks. one. melatonin b. slow wave sleep c. sleep deprivation d. growing hormone

15. The most common treatment for ________ involves taking amphetamine-like drugs.

9. ________ is (are) described as slow-wave sleep. one. Phase 1b. Stage 2 c. Phase 3 and Phase 4 d. REM sleep

one. B. ç. d.

Sleep Apnea RBD SIDS Narcolepsy

16. ________ is another word for sleepwalking. one. insomnia b. sleepwalking c. cataplexy d. narcolepsy


17. ________ Occurs when a drug user requires increasing amounts of a given drug to experience the same drug effects. one. resign b. psychological dependence c. tolerance D. Resumption 18. Cocaine blocks the resumption of ________. one. GABA b. glutamate c. acetylcholine D. Dopamine 19. ________ refers to craving for drugs. one. psychological dependence b. antagonism c. agonism d. physical dependence 20. LSD affects ________ neurotransmission. one. dopamine b. serotonin c. acetylcholine D. noradrenaline

Chapter 5 | states of consciousness

21. ________ is most effective with people who are very open to the power of suggestion. one. hypnosis b. meditation c. conscious awareness d. cognitive therapy 22. ________ has its roots in religious practice. one. hypnosis b. meditation c. cognitive therapy d. Behavior Therapy 23. Meditation can be helpful with _______. one. pain control b. stress management c. Influenza treatment d. both a and b 24. Research suggests that cognitive processes such as B. Learning can be influenced by ________. one. hypnosis b. meditation c. conscious awareness d. progressive relaxation

Critical Thinking Issues 25. Health professionals often work in rotating shifts. Why is this problematic? What can be done to solve possible problems? 26. In general, humans are considered diurnal, meaning that we are awake during the day and sleep at night. Many rodents, on the other hand, are nocturnal. Why do you think different animals have such different sleep-wake cycles? 27. If the theories that claim sleep is necessary for recovery and recovering from daily energy demands are correct, what do you predict about the relationship that would exist between people's total sleep duration and their activity level? 28. How can researchers determine whether certain brain areas are involved in sleep regulation? 29. Differentiate between evolutionary theories of sleep and defend the one with the most convincing evidence. 30. Freud believed that dreams provide important insights into the unconscious. He claimed that the manifest content of a dream could provide clues to a person's unconscious. What are possible criticisms of this particular perspective? 31. Some people claim that sleepwalking and sleep talking make people act out their dreams. Why is this particular explanation unlikely?

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32. One of the recommendations therapists will make to people with insomnia is to spend less time awake in bed. Why do you think spending hours awake in bed can interfere with your ability to fall asleep later? 33. How is narcolepsy with cataplexy different from REM sleep? 34. The negative health consequences of alcohol and tobacco are well documented. On the other hand, a drug like marijuana is generally considered to be just as, if not more, safe than these legal drugs. Why do you think marijuana use remains illegal in many parts of the United States? 35. Why are programs to educate people about the dangers of using tobacco products as important as developing programs to stop smoking? 36. What are the merits of researching the potential health benefits of hypnosis? 37. What types of studies would be most convincing regarding the effectiveness of meditation in treating physical or mental disorders?

Personal Application Issues 38. We experience changes in our circadian clocks in the fall and spring of each year, with time changes associated with daylight saving time. Is it easier for you to adjust to jumping ahead or staying behind, and why do you think this is? 39. What do you do to adjust to differences in your daily routine during the week? Do you have a sleep debt when Daylight Saving Time starts or ends? 40. Have you (or anyone you know) ever experienced significant periods of sleep deprivation due to simple insomnia, high stress, or a side effect of a medication? What were the consequences of lack of sleep? 41. Researchers believe that an important function of sleep is to facilitate learning and memory. How does this knowledge help you in your studies? What changes could you make to your study and sleep habits to maximize your mastery of the material covered in class? 42. What factors might contribute to your own insomnia experience? 43. Many people experiment with some type of psychoactive substance at some point in their lives. Why do you think people are motivated to use mind-altering substances? 44. Under what circumstances would you be willing to consider hypnosis and/or meditation as a treatment option? What kind of information do you need before deciding to use these techniques?


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Chapter 6


Figure 6.1 Loggerhead turtle hatchlings are born knowing how to find the ocean and how to swim. Unlike sea turtles, humans have to learn to swim (and surf). (Turtle Credit: Modified work by Becky Skiba, USFWS; Surfer Credit: Modified work by Mike Baird)

Chapter overview 6.1 What is learning? 6.2 Classical conditioning 6.3 Operant conditioning 6.4 Observational learning (modeling)

Introduction The summer sun shines brightly on a secluded stretch of beach. Suddenly, a small gray head emerges from the sand, then another and another. Soon the beach is teeming with loggerhead turtle hatchlings (Figure 6.1). Even though they are only a few minutes old, the puppies know exactly what to do. Their fins aren't very efficient at navigating the hot sand, but they instinctively keep moving. Some are quickly picked up by gulls circling overhead, and others become lunch for hungry ghost crabs crawling out of their holes. Despite these dangers, chicks are driven to leave the safety of their nest and find the ocean. Not far from the same beach, Ben and his son Julian paddle out to sea on surfboards. A wave approaches. Julian crouches down on his board, then jumps and rides the wave for a few seconds before losing his balance. He climbs out of the water just in time to see his dad ride the wave. Unlike baby sea turtles, who know how to find the ocean and swim without parental help, we are not born knowing how to swim (or surf). We humans are proud of our ability to learn. In fact, over thousands of years and across cultures, we have created institutions dedicated solely to learning. But have you ever wondered how exactly we learn? What processes occur when we know what we know? This chapter focuses on the main ways in which learning takes place.


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6.1 What is learning? Learning Objectives By the end of this section, you will be able to: • Explain how learned behavior differs from instincts and reflexes • Define learning • Identify and define three basic forms of learning – classical conditioning, operant conditioning, and observational learning Birds build nests and migrate when sewing winter. Babies suck on their mother's breast. Dogs shake water off their wet fur. Salmon swim upstream to spawn and spiders spin intricate webs. What do these seemingly unrelated behaviors have in common? They are all unlearned behaviors. Both instincts and reflexes are innate behaviors that organisms are born with. Reflexes are a motor or neural response to a specific stimulus in the environment. They tend to be simpler than instincts, involving the activity of specific parts and systems of the body (eg spinal cord and medulla). In contrast, instincts are innate behaviors that are triggered by a wider range of events, such as aging and the change of seasons. These are more complex patterns of behavior, involving movements of the organism as a whole (eg, sexual activity and migration) and involving higher brain centers. Both reflexes and instincts help an organism to adapt to its environment and do not need to be learned. For example, every healthy human baby has a sucking reflex that is present from birth. Babies are born knowing that they can suck on a teat, whether artificial (from a bottle) or human. No one teaches a baby to nurse any more than anyone teaches a sea turtle to move toward the ocean. Learning, like reflexes and instincts, allows an organism to adapt to its environment. But unlike instincts and reflexes, learned behaviors involve change and experience: learning is a relatively permanent change in behavior or knowledge that results from experience. In contrast to the innate behaviors discussed above, learning involves acquiring knowledge and skills through experience. Looking back on our surfing scene, Julian needs to spend a lot more time training with his board before he learns to ride the waves like his dad. Learning to surf, like any complex learning process (eg learning the subject of psychology) involves a complex interplay of conscious and unconscious processes. Learning has traditionally been studied in terms of its simplest components - the associations our brains automatically make between events. Our minds have a natural tendency to connect events that occur together or one after the other. Associative learning occurs when an organism makes connections between stimuli or events that occur together in the environment. You will see that associative learning is central to all three of the basic learning processes discussed in this chapter; Classical conditioning tends to involve unconscious processes, operant conditioning tends to involve conscious processes, and observational learning adds social and cognitive layers to all basic associative processes, both conscious and unconscious. These learning processes are discussed in detail later in this chapter, but it is helpful to have a brief overview of each as you begin to examine how learning is understood from a psychological perspective. In classical conditioning, also known as Pavlovian conditioning, organisms learn to associate events - or stimuli - that occur repeatedly together. We experience this process in the course of our daily lives. For example, during a thunderstorm, you might see lightning in the sky and then hear a loud thunderclap. The sound of thunder naturally makes you jump (loud sounds have this reflexive effect). Since lightning reliably predicts oncoming lightning, when you see lightning, you can associate the two and jump. Psychological researchers study this associative process by focusing on what can be seen and measured - behaviors. Researchers ask if a stimulus elicits a reflex, can we train another stimulus to elicit the same reflex? In turn, in operant conditioning, organisms learn to associate events – a behavior and its consequence (reinforcement or punishment). An enjoyable episode encourages more

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of this behavior in the future, while punishment deters the behavior. Imagine teaching your dog Hodor to sit. You tell Hodor to sit down and give him a treat when he does. After repeated experiences, Hodor begins to associate sitting with receiving a treat. He learns that sitting results in getting a dog biscuit (Figure 6.2). On the other hand, if the dog is punished when it exhibits a behavior, it will be conditioned to avoid that behavior (for example, receiving a small shock when crossing the boundary of an invisible electric fence).

Figure 6.2 In operant conditioning, a response is associated with a consequence. This dog has learned that certain behaviors will result in receiving a treat. (Image credit: Crystal Rolfe)

Observational learning expands the scope of classical and operant conditioning. Unlike classical and operant conditioning, where learning occurs only through direct experience, observational learning is the process of observing others and then imitating what they do. Much of learning in humans and other animals is based on observational learning. To get an idea of ​​the additional effective reach that observational learning brings, consider Ben and his son Julian from the beginning. How can observation help Julian learn to surf instead of just learning through trial and error? By watching his father, he can imitate the steps that bring success and avoid the steps that lead to failure. Can you think of something you learned after watching someone else? All of the approaches discussed in this chapter are part of a specific tradition in psychology called behaviorism, which we will discuss in the next section. However, these approaches do not represent the whole study of learning. Separate learning traditions have emerged in different areas of psychology, such as memory and cognition, so you will find that other chapters will complement your understanding of the subject. Over time, these traditions tend to grow together. For example, in this chapter you will see how cognition plays a major role in behaviorism, whose most extreme adherents insisted that behaviors are triggered by the environment without the intervention of thought.

6.2 Classical Conditioning Learning Objectives By the end of this section, you will be able to: • explain how classical conditioning works • summarize the processes of acquisition, extinction, spontaneous recovery, generalization and discrimination Are you familiar with the name Ivan Pavlov? Even if you're new to the study of psychology, you've probably heard of Pavlov and his famous dogs.


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Pavlov (1849-1936), a Russian scientist, did extensive research on dogs and is best known for his experiments in classical conditioning (Figure 6.3). As we briefly discussed in the previous section, classical conditioning is a process by which we learn to associate stimuli and, consequently, to anticipate events.

Figure 6.3 Ivan Pavlov's research on the canine digestive system unexpectedly led to the discovery of the learning process now known as classical conditioning.

Pavlov came to his conclusions about how learning happens completely at random. Pavlov was a physiologist, not a psychologist. Physiologists study the vital processes of organisms, from the molecular level to the level of cells, organ systems and entire organisms. Pavlov's area of ​​interest was the digestive system (Hunt, 2007). In his dog studies, Pavlov surgically implanted tubes into the dogs' cheeks to collect saliva. Then he measured the amount of saliva produced in response to different foods. Over time, Pavlov (1927) observed that dogs began to drool not only at the taste of food, but also at the sight of food, at the sight of an empty food bowl, and even at the sound of laboratory workers. ' steps. The flow of saliva for eating in the mouth is reflexive, so no learning is involved. However, dogs don't drool at the sight of an empty bowl or the sound of footsteps. Fascinated by these unusual reactions, Pavlov wondered what was responsible for what he called the "psychic secretions" of dogs (Pavlov, 1927). To study this phenomenon objectively, Pavlov designed a series of carefully controlled experiments to see which stimuli would make dogs salivate. He was able to train the dogs to salivate in response to stimuli clearly unrelated to food, such as the sound of a bell, a light and a tap on the leg. Through his experiments, Pavlov realized that an organism has two types of responses to its environment: (1) unconditional (not learned) responses or reflexes and (2) conditioned (learned) responses. In Pavlov's experiments, dogs salivated whenever they were presented with powdered meat. The meat powder in this situation was an unconditional stimulus (UCS): a stimulus that elicits a reflexive response in an organism. The dogs' salivation was an unconditioned response (UCR): a natural (not learned) response to a given stimulus. Before conditioning, imagine the dog's stimulus and response as follows: Meat Powder (UCS) → Salivation (UCR) In classical conditioning, a neutral stimulus is presented immediately before an unconditional stimulus. Pavlov made a sound (like ringing a bell) and then fed the powdered meat to the dogs (Figure 6.4). The tone was the neutral stimulus (NS), a stimulus that does not naturally elicit a response. Before conditioning, the dogs did not salivate when they just heard the sound because the sound had no connection to the dogs. Very simply, this pairing means: Clay (NS) + Meat Powder (UCS) → Salivation (UCR) When Pavlov paired Clay with Meat Powder repeatedly, the previously neutral stimulus was

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(the sound) also started to make the dogs salivate. Thus, the neutral stimulus became the conditioned stimulus (CS), a stimulus that elicits a response after being repeatedly paired with an unconditioned stimulus. Finally, the dogs began to drool at the sound alone, just as they had previously drooled at the sound of the assistants' footsteps. The behavior caused by the conditioned stimulus is called a conditioned response (CR). In the case of Pavlov's dogs, they learned to associate tone (CS) with eating and began to salivate (CR) in anticipation of food. Tone (CS) → Salivation (CR)

Figure 6.4 Before conditioning, an unconditioned stimulus (food) elicits an unconditioned response (salivation) and a neutral stimulus (bell) elicits no response. During conditioning, the unconditioned stimulus (eating) is repeatedly presented immediately after the neutral stimulus (bell) is presented. After conditioning, the neutral stimulus alone produces a conditioned response (salivation) and thus becomes a conditioned stimulus.

LINK TO LEARN Now that you've learned the classical conditioning process, do you think you can condition Pavlov's dog? Visit this website ( to play.

LINK TO LEARN Watch this video ( to learn more about Pavlov and his dogs.

REAL APPLICATIONS OF CLASSICAL CONDITIONING How does classical conditioning work in the real world? Let's say you have a cat named Tiger who is quite finicky. They keep the food in a separate cupboard and have a special electric can opener for that too.


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They only use it to open cans of cat food. With each meal, Tiger hears the characteristic sound of the electric can opener ("zzhzhz") and then takes his food. Tiger quickly realizes that she is about to be fed when she hears "zzhzhz". What do you think Tiger does when he hears the electric can opener? She will probably get excited and run to where you are preparing her food. This is an example of classical conditioning. What are UCS, CS, UCR and CR in this case? What if the cupboard with Tiger's food creaks? In this case, Tiger hears "squeak" (the cupboard), "zzhzhz" (the electric can opener), and then she reaches for her food. Tiger will learn to get emotional when he hears the "creak" of the closet. The pairing of a new neutral stimulus (“squeak”) with the conditioned stimulus (“zzhzhz”) is called higher-order or second-order conditioning. This means that you use the conditioned stimulus of the can opener to condition another stimulus: the noisy closet (Figure 6.5). It's hard to get anything beyond second-order conditioning. For example, if you ring a bell, open the cupboard ("squeak"), use the can opener ("zzhzhz"), and feed Tiger, Tiger will probably never get excited when he hears the bell alone.

Figure 6.5 In higher-order conditioning, an established conditioned stimulus is paired with a new neutral stimulus (the second-order stimulus) so that the new stimulus eventually elicits the conditioned response as well, without presenting the initial conditioned stimulus.

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DAILY CONNECTION Classic conditioning in Stingray City Kate and her husband Scott recently vacationed in the Cayman Islands and booked a boat trip to Stingray City, where they were able to feed and swim with southern stingrays. The boat captain explained how the normally solitary stingrays got used to dealing with people. About 40 years ago, fishermen started cleaning fish and clams (mandatory response) on a certain sandbar next to a barrier reef, and large numbers of stingrays came in to eat (mandatory response), which the fishermen threw into the Water; it was like that for years. In the late 1980s, word of the large group of stingrays spread among divers, who began hand-feeding them. Over time, the area's southern stingrays became classically conditioned, much like Pavlov's dogs. Upon hearing the sound of a boat engine (neutral stimulus that becomes a conditioned stimulus), they know they are going to eat (conditioned response). Once Kate and Scott arrived in Stingray City, more than two dozen stingrays surrounded their tour boat. The pair waded into the water with bags full of squid, the stingray's favorite treat. The school of stingrays nudged and rubbed their legs like hungry cats (Figure 6.6). Kate and Scott fed, petted and (thankfully) even kissed these amazing creatures. Then all the squid were gone and so were the stingrays.

Figure 6.6 Kate holds a southern stingray in Stingray City, Cayman Islands. These stingrays have been classically conditioned to associate the sound of a boat engine with food provided by tourists. (Credit: Kathryn Dumper)

Classical conditioning also applies to humans, even babies. For example, Sara buys baby formula in blue jars for her six-month-old daughter, Angelina. Whenever Sara takes a container of milk, Angelina becomes agitated, tries to get the food and probably salivates. Why does Angelina get upset when she sees the formula can? What are UCS, CS, UCR and CR here? All the examples so far have involved food, but classical conditioning goes beyond the basic need to be fed. Consider our earlier example of a dog whose owners install an invisible electric dog fence. A small electric shock (unconditional stimulus) triggers discomfort (unconditional response). When the unconditional stimulus (shock) is paired with a neutral stimulus (yard edge), the dog associates the discomfort (unconditioned response) with the yard edge (conditioned stimulus) and stays within established limits. In this example, the edge of the yard provokes fear and restlessness in the dog. Fear and worry are the conditioned response.

LINK TO LEARN For a humorous look at conditioning, watch this video clip ( from the television show The Office, in which Jim Dwight conditions each time Jim's computer performs a specific statement makes, expect a minty sound.


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GENERAL PROCESSES IN CLASSICAL CONDITIONING Now that you know how classical conditioning works and have seen some examples, let's look at some of the general processes involved. In classical conditioning, the initial learning phase is called acquisition, when an organism learns to associate a neutral stimulus and an unconditional stimulus. During acquisition, the neutral stimulus begins to elicit the conditioned response, and eventually the neutral stimulus becomes a conditioned stimulus capable of eliciting the conditioned response itself. Timing is important for conditioning to take place. Normally, there should be only a short interval between the presentation of the conditioned stimulus and the unconditional stimulus. Depending on what is being conditioned, this interval is sometimes as little as five seconds (Chance, 2009). With other types of conditioning, however, the interval can be several hours. Taste aversion is a form of conditioning in which a gap of several hours may elapse between the conditioned stimulus (something eaten) and the unconditional stimulus (nausea or illness). Here's how it works: Between classes, you and a friend grab a quick lunch at a food truck on campus. You share a dish of chicken curry and move on to the next class. A few hours later, you feel queasy and queasy. Even though your friend is fine and you realize you have the flu (food isn't to blame), you've developed an aversion to taste; The next time you're at a restaurant and someone orders curry, you're going to feel nauseous. Although the chicken dish didn't make you sick, you experience a taste aversion: you've been conditioned to have an aversion to the food after a single negative experience. How does this happen – conditioning based on a single event and with a longer period of time between the event and the negative stimulus? Research on taste aversion suggests that this response may be an evolutionary adaptation designed to help organisms quickly learn to avoid harmful foods (Garcia & Rusiniak, 1980; Garcia & Koelling, 1966). Not only can this contribute to the survival of the species through natural selection, but it can also help us create strategies to face challenges such as & Wismer, 2007; Skolin et al., 2006). Once we've made the connection between the unconditioned stimulus and the conditioned stimulus, how can we break that connection and get the dog, cat, or child to stop responding? In the case of Tigre, imagine what would happen if you stopped using the electric can opener on food and started using it only on human food. Now Tiger listened to the can opener but couldn't get any food. In classical conditioning, you would give the conditioned stimulus but not the unconditioned stimulus. Pavlov explored this scenario in his experiments with dogs: getting the pitch right without giving the dogs powdered meat. Soon the dogs stopped responding to the sound. Extinction is the diminution of the conditioned response when the unconditioned stimulus is no longer presented with the conditioned stimulus. If the conditioned stimulus were presented alone, the dog, cat, or other organism would show an increasingly weaker response, and eventually no response at all. In terms of classical conditioning, there is a gradual weakening and disappearance of the conditioned response. What happens when learning is not used for a while - when what has been learned is dormant? As just discussed, Pavlov found that when he repeatedly presented the bell (conditioned stimulus) without the powdered meat (conditioned stimulus), extinction occurred; the dogs stopped salivating at the sound of the bell. However, after a few hours of recovery from this extinction training, the dogs started drooling again when Pavlov rang the bell. What do you think would happen to Tiger's behavior if your electric can opener broke and you didn't use it for several months? When you finally got it fixed and started opening Tiger's food again, Tiger remembered the connection between the can opener and her food - she would get excited and run to the kitchen when she heard the sound. The behavior of Pavlov's dogs and tigers illustrates a concept Pavlov calls spontaneous recovery: the return of a previously extinguished conditioned response after a period of rest (Figure 6.7).

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Figure 6.7 This is the acquisition, absorbance and spontaneous recovery curve. The rising curve shows that the conditioned response rapidly increases in strength through repeated pairing of the conditioned stimulus and the unconditional stimulus (acquisition). Then the curve decreases, showing how the conditioned response weakens when only the conditioned stimulus is presented (extinction). After an interruption or pause in conditioning, the conditioned response reappears (spontaneous recovery).

Of course, these processes apply to humans as well. For example, let's say that every day, when you go to campus, an ice cream truck passes your way. Day after day you listen to the truck music (neutral stimulus), then eventually you stop and buy a chocolate ice cream bar. You take a bite (conditioned stimulus) and then your mouth waters (conditioned response). This initial learning phase is called acquisition, when you begin to associate the neutral stimulus (the sound of the truck) and the unconditional stimulus (the taste of chocolate ice cream in your mouth). During acquisition, the conditioned response becomes progressively stronger through repeated pairings of the conditioned stimulus and the unconditioned stimulus. A few days (and ice cream bars) later, you start salivating (conditioned response) to the musical sound of the truck - before you even bite into the ice cream bar. Then one day you're walking down the street. You hear the truck music (conditioned stimulus) and your mouth waters (conditioned response). However, when he arrives at the truck, he realizes that they are all out of ice. You leave disappointed The next few days, you pass the truck and listen to the music, but you don't stop to buy an ice cream shop because you're late for class. You start salivating less and less when you hear the music, until by the end of the week your mouth isn't watering when you hear the music. This illustrates extinction. The conditioned response decreases when only the conditioned stimulus (the sound of the truck) is presented without being followed by the unconditional stimulus (chocolate ice cream in the mouth). Then comes the weekend. You don't have to go to class, so don't drive past the truck. Monday morning arrives and you take your usual route to campus. You turn the corner and hear the truck again. What do you think happened? Your mouth starts watering again. Because? After a break from conditioning, the conditioned response reappears, indicating spontaneous recovery. Acquisition and extinction involve strengthening and weakening, respectively, of a learned association. Two other learning processes—stimulus discrimination and stimulus generalization—are involved in distinguishing which stimuli trigger the learned association. Animals (including humans) must discriminate between stimuli – for example, between sounds that predict a threatening event and sounds that do not – in order for them to respond appropriately (for example, flee if the sound is threatening). When an organism learns to react differently to different similar stimuli, we speak of stimulus discrimination. In the classical language of conditioning, the organism shows the conditioned response only to the conditioned stimulus. Pavlov's dogs distinguished between the root tone that sounded before feeding and other tones (e.g., the bell) because the other tones were unpredictable.


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the arrival of the food. Similarly, the cat Tiger distinguished between the sound of the can opener and the sound of the mixer. When the electric blender is running, Tiger isn't being fed, so she doesn't run to the kitchen looking for food. On the other hand, when an organism exhibits the conditioned response to stimuli that resemble the condition stimulus, this is called stimulus generalization, the opposite of stimulus discrimination. The more similar a stimulus is to the conditional stimulus, the more likely the organism is to give the conditioned response. For example, if the noise of the electric blender is very similar to that of the electric can opener, the Tiger may come running at the sound of it. But if you don't feed her the sound of the electric blender and continue to consistently feed her the sound of the electric can opener, she will quickly learn to distinguish between the two sounds (assuming they are so different that you can tell them apart). 🇧🇷 Classical conditioning can sometimes lead to habituation. Habituation occurs when we learn not to respond to a stimulus that is presented repeatedly without change. As the stimulus keeps coming back, we learn not to focus our attention on it. Imagine, for example, that your neighbor's or roommate's TV is constantly on. This background noise is distracting and makes it difficult to concentrate while studying. But over time, you get used to the excitement of TV noise and at some point you hardly notice it anymore.

BEHAVIORISM John B. Watson, shown in Figure 6.8, is considered the founder of behaviorism. Behaviorism is a school of thought that emerged in the first half of the 20th century and incorporates elements of Pavlov's classical conditioning (Hunt, 2007). In stark contrast to Freud, who kept the reasons for behavior hidden in the unconscious, Watson proposed the idea that all behavior can be studied as a simple stimulus-response response, without regard to internal processes. Watson argued that for psychology to become a legitimate science, it must turn its attention away from internal mental processes, since mental processes cannot be seen or measured. Instead, he asserted that psychology should focus on externally observable behavior that can be measured.

Figure 6.8 John B. Watson used the principles of classical conditioning in the study of human emotions.

Watson's ideas were influenced by Pavlov's work. According to Watson, human behavior, like animal behavior, is primarily the result of conditioned responses. While Pavlov's work with dogs involved reflex conditioning, Watson believed that the same principles could be extended to human emotional conditioning (Watson, 1919). Thus began Watson's work with his student Rosalie Rayner and a baby named Little Albert. Through their experiments with little Albert, Watson and Rayner (1920) showed how fear can be conditioned. In 1920, Watson was chair of the psychology department at Johns Hopkins University. Through his position at the university, he met little Albert's mother, Arvilla Merritte, who worked on a campus

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hospital (DeAngelis, 2010). Watson offered her a dollar so that her son could be the subject of her classic conditioning experiments. Through these experiments, little Albert was exposed to certain things and conditioned to fear certain things. First, he was presented with a variety of neutral stimuli, including a rabbit, a dog, a monkey, masks, cotton wool, and a white mouse. He wasn't afraid of any of those things. Then, with Rayner's help, Watson conditioned little Albert to associate these stimuli with an emotion—fear. For example, Watson gave little Albert the white mouse, and little Albert liked to play with it. Watson then made a loud noise by hitting a metal rod hanging behind Little Albert's head with a hammer each time Little Albert touched the mouse. Little Albert was startled by the noise - he showed a reflex fear of sudden loud noises - and began to cry. Watson repeatedly paired the loud sound with the white mouse. Soon little Albert alone was afraid of the white mouse. What are UCS, CS, UCR and CR in this case? Days later, little Albert showed stimulus generalization – he became afraid of other furry things: a rabbit, a furry coat, and even a Santa Claus mask (Figure 6.9). Watson was able to condition a fear response in Little Albert, demonstrating that emotions can become conditioned responses. Watson's intention was to create a phobia - a persistent and excessive fear of a particular object or situation - through conditioning alone, thus contradicting Freud's view that phobias are caused by deep, hidden conflicts in the mind. However, there is no evidence that little Albert has had phobias in recent years. Little Albert's mother moved out and ended the experiment. While Watson's research provided new insight into conditioning, it would be considered unethical by today's standards.

Figure 6.9 Through stimulus generalization, little Albert began to fear furry things, including Watson in a Santa Claus mask.

LINK TO LEARN View footage from John Watson's experiment ( in which little Albert was conditioned to react anxiously to furry objects. As you watch the video, pay close attention to Little Albert's responses and the way Watson and Rayner present the pre- and post-conditioning stimuli. Based on what you see, would you reach the same conclusions as the researchers?

DAILY CONNECTION Advertising and Associative Learning Advertisers are professionals in applying the principles of Associative Learning. Think of the car commercial you saw on TV. Many of them have an attractive model. By associating the model with the advertised car, you see the car as desirable (Cialdini, 2008). You might be wondering if this advertising technique really works? According to Cialdini (2008), men who saw a car ad with an attractive model later rated the car as faster, more attractive and better.


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conceived as men who watched an advertisement for the same car without the model. Have you ever noticed how quickly advertisers terminate contracts with a famous athlete after a scandal? From the advertiser's perspective, this athlete is no longer associated with positive feelings; Therefore, the athlete cannot be used as an unconditional stimulus to condition the audience to associate positive feelings (the unconditional response) with your product (the conditioned stimulus). Now that you understand how associative learning works, see if you can find examples of this type of advertising on TV, in magazines, or on the Internet.

6.3 Learning Objectives for Operant Conditioning By the end of this section, you will be able to: • define operant conditioning • explain the difference between reinforcement and punishment • distinguish between reinforcement schedules The previous section of this chapter focused on the type of associative learning known as conditioning classic. Remember that in classical conditioning, something in the environment automatically triggers a reflex, and researchers train the body to respond to a different stimulus. We now turn to the second type of associative learning, operant conditioning. In operant conditioning, organisms learn to associate behavior and its consequences (Table 6.1). A pleasant consequence makes it more likely that this behavior will be repeated in the future. For example, Spirit, a dolphin at the National Aquarium in Baltimore, does a somersault in the air when its trainer blows the whistle. The result is that she gets a fish. A Comparison of Classical and Operant Conditioning

classical conditioning

operant conditioning

conditioning approach

An unconditional stimulus (eg food) is paired with a neutral stimulus (eg a bell). The neutral stimulus eventually becomes the conditioned stimulus, which elicits the conditioned response (salivation).

The target behavior is followed by reinforcement or punishment to reinforce or weaken it so that the student is more likely to exhibit the desired behavior in the future.

Stimulus Timing

The stimulus occurs immediately before the response.

The stimulus (reinforcement or punishment) occurs shortly after the response.

Table 6.1

Psychologist B.F. Skinner saw that classical conditioning is limited to existing behaviors that are reflexively triggered and does not take into account new behaviors such as riding a bicycle. He proposed a theory of how such behaviors happen. Skinner believed that behavior is motivated by the consequences we receive for behavior: the reinforcements and punishments. His idea that learning is the result of

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Consequences is based on the law of effect first proposed by psychologist Edward Thorndike. According to the law of effect, behaviors followed by satisfactory results for the organism are more likely to be repeated, and behaviors followed by unpleasant results are less likely to be repeated (Thorndike, 1911). Essentially, when an organism does something that leads to a desired result, the organism is more likely to do it again. If an organism does something that does not produce the desired result, the organism is less likely to do it again. An example of the law of action is employment. One of the reasons (and often the main reason) we show up for work is because we get paid for it. If we don't get paid more, we probably won't come back - even if we love our work. Using Thorndike's law of action as a basis, Skinner began conducting scientific experiments on animals (mainly rats and pigeons) to determine how organisms learn through operant conditioning (Skinner, 1938). He placed these animals in an operant conditioning chamber that became known as a "Skinner box" (Figure 6.10). A Skinner box contains a lever (for rats) or disc (for pigeons) that the animal can push or peck to receive a food reward through the dispenser. Speakers and lights can be assigned specific behaviors. A recorder counts the number of animal responses.

Figure 6.10 (a) B. F. Skinner developed operant conditioning to systematically study how behaviors are reinforced or weakened depending on their consequences. (b) In a Skinner box, a rat presses a lever in an operant conditioning chamber to receive a food reward. (Credit to: Modification of work by "Silly Rabbit"/Wikimedia Commons)

LINK TO LEARN To learn more about operant conditioning, watch this short video clip ( Skinner is interviewed and operant conditioning of pigeons is demonstrated.

When discussing operant conditioning, we use several everyday words – positive, negative, reinforcement and punishment – ​​in specific ways. In operant conditioning, positive and negative do not mean good and bad. Instead, positive means you are adding and negative means you are taking away. Reinforcement means you reinforce a behavior and punishment means you decrease a behavior. Reinforcement can be positive or negative, and punishment can also be positive or negative. All reinforcers (positive or negative) increase the likelihood of a behavioral response. All punishers (positive or negative) decrease the likelihood of a behavioral response. Now let's combine these four terms: positive reinforcement, negative reinforcement, positive punishment, and negative punishment (Table 6.2).


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Positive and negative reinforcement and punishment




Something is added to increase the likelihood of a behavior.

Something is added to reduce the likelihood of a behavior.


Something is removed to increase the likelihood of a behavior.

Something is removed to reduce the likelihood of a behavior.

Table 6.2

REINFORCEMENT The most effective way to teach a person or animal a new behavior is through positive reinforcement. In positive reinforcement, a desired stimulus is added to reinforce a behavior. For example, you tell your five-year-old son, Jerome, that if he cleans his room, he will get a toy. Jerome quickly tidies up his room because he wants a new art set. Let's stop for a moment. Some people might say, “Why should I reward my child for doing what is expected?” But the truth is, we are constantly and consistently rewarded in our lives. Our paychecks are rewards, just like good grades and admission to our favorite school. Praise for good work and passing driving tests are also a reward. Positive reinforcement as a learning tool is extremely effective. It turned out that one of the most effective ways to improve performance in underperforming school districts was to pay children to read. Specifically, second graders in Dallas were paid $2 each time they read a book and passed a short test about the book. The result was a significant increase in reading comprehension (Fryer, 2010). What do you think of this program? If Skinner were alive today, he would probably think it was a great idea. He was a strong advocate of using operant conditioning principles to influence student behavior in school. In fact, in addition to the Skinner box, he also invented what he called a teaching machine designed to reward small steps in learning (Skinner, 1961) – an early forerunner of computer-assisted learning. His Teaching Machine tested students' knowledge as they worked on various school subjects. If students answered the questions correctly, they received immediate positive confirmation and could continue; if they answered incorrectly, they received no reinforcements. The idea was that students would spend more time studying the material to increase their chance of being strengthened next time (Skinner, 1961). Negative reinforcement removes an unwanted stimulus to reinforce a behavior. For example, car manufacturers use the principle of negative reinforcement in their seat belt systems, which go "beep, beep, beep" until you buckle your seat belt. The annoying noise stops when you engage in the desired behavior, making it more likely that you'll buckle up in the future. Negative reinforcement is also commonly used in horse training. Riders apply pressure — tugging on the reins or pinching the legs — and then release the pressure when the horse performs a desired behavior, such as stopping. B. turn or accelerate. Pressure is the negative stimulus the horse wants to remove.

PUNISHMENT Many people confuse negative reinforcement with punishment in operant conditioning, but they are two very different mechanisms. Remember that reinforcement, even if it is negative, always reinforces a behavior. In contrast, punishment always mitigates behavior. With positive punishment, you add an unwanted stimulus to decrease a behavior. An example of positive punishment is scolding a student to stop texting during class. In this case, a stimulus (the scolding) is added to reduce the behavior (texting in class). With negative punishment, you remove a pleasurable stimulus to decrease the behavior. For example, if a child misbehaves, a parent might take away a favorite toy. In this case, a stimulus (the toy) is removed to reduce the behavior.

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Punishment, especially when done immediately, is a way to reduce unwanted behavior. For example, imagine that your four-year-old son, Brandon, hits his younger brother. They make Brandon write "I won't hit my brother" (positive punishment) 100 times. He probably won't repeat this behavior. While strategies like these are common today, in the past children were often physically punished, such as spanking. It is important to be aware of some disadvantages when children are physically punished. First, punishment can teach fear. Brandon might be afraid of the street, but he might also be afraid of the person who administered the punishment - you, his father. Likewise, children who are punished by teachers may fear the teacher and try to avoid school (Gershoff et al., 2010). Consequently, most schools in the United States have banned corporal punishment. Second, punishment can cause children to become more aggressive and more prone to antisocial behavior and delinquency (Gershoff, 2002). make angry and frustrated. For example, because you hit Brenda when you're mad at her for her mistake, she might start hitting her friends if they don't share her toys. While positive punishment can be effective in some cases, Skinner suggested that the use of punishment must be balanced against possible negative effects. Psychologists and parenting experts today prefer reinforcement to punishment - they recommend that you catch your child doing good and reward him.

Modeling In his operant conditioning experiments, Skinner often used an approach called modeling. Rather than just rewarding target behavior, in modeling we reward successive approximations of a target behavior. Why is modeling necessary? Remember that for reinforcement to work, the organism must first exhibit the behavior. Modeling is necessary because it is extremely unlikely that an organism will spontaneously exhibit anything other than the simplest behaviors. Modeling breaks down behaviors into many small, achievable steps. The specific steps used in the process are as follows: 1. Reinforce any response that resembles the desired behavior. 2. Then reinforce the response that most closely resembles the desired behavior. you won't anymore

amplify the previously amplified response. 3. Then start reinforcing the response that most closely resembles the desired behavior. 4. Continue to reinforce closer and closer approximations to the desired behavior. 5. Finally, reinforce only the behavior you want.

Modeling is often used to teach a complex behavior or chain of behaviors. Skinner used modeling to teach pigeons not only relatively simple behaviors like pecking a disc in a Skinner box, but also many unusual and fun behaviors like spinning in circles, walking on figure eights and even playing table tennis. The technique is now commonly used by animal trainers. An important part of modeling is stimulus differentiation. Remember Pavlov's dogs - he taught them to respond to the sound of a bell, and not similar tones or noises. This distinction is also important in operant conditioning and behavior design.

LINK TO LEARN Here is a short video ( of Skinner's pigeons playing table tennis.

It's easy to see how effective modeling is for teaching animals behaviors, but how does modeling work with this?


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People? Consider parents whose goal is for their children to learn to tidy their rooms. They use modeling to help you master the steps towards the goal. Rather than running the entire task, they lay out those steps and reinforce each step. First he cleans a toy. Second, he cleans five toys. Third, he decides whether to pick up ten toys or put away his books and clothes. Fourth, he cleans all but two toys. Finally, he cleans the entire room.

PRIMARY AND SECONDARY REINFORCEMENTS Rewards such as stickers, praise, money, toys, and more can be used to reinforce learning. Let's go back to Skinner's rats. How did the rats learn to pull the lever on Skinner's box? They were rewarded with food every time they pushed the lever. For animals, food would be an obvious reinforcer. What would be a good booster for humans? For her daughter Sydney, tidying her room was the promise of a toy. How about Joaquin the football player? If you gave Joaquin a candy every time he scores, you would use a primary reinforcer. Primary reinforcers are reinforcers that have innate reinforcing qualities. These types of reinforcers are not learned. Water, food, sleep, protection, sex, and touch are among the primary reinforcers. Joy is also a primary reinforcer. Organisms don't lose the urge to do these things. For most people, jumping into a cool lake on a very hot day would be invigorating, and the cool lake would be inherently invigorating - the water would refresh one (a physical need) and also be pleasurable. A secondary reinforcer has no inherent value and only has reinforcing properties when coupled with a primary reinforcer. Praise along with affection is an example of secondary reinforcement, like when you shouted "Great shot!" Every time Joaquin scored a goal. As another example, money is only worth something if you can use it to buy other things—be it things that meet basic needs (food, water, shelter—all primary reinforcers) or other secondary reinforcers. If you were on a remote island in the middle of the Pacific Ocean and you had a lot of money, the money would be useless if you couldn't spend it. What about the stickers on the behavior chart? They are also secondary reinforcers. Sometimes a token is used instead of stickers in a sticker chart. Tokens, which are also secondary boosters, can be exchanged for rewards and prizes. Entire behavior management systems known as token economies are based on the use of these types of token reinforcers. Token economies have proven to be very effective in changing behavior in a variety of settings such as schools, prisons and mental hospitals. For example, a study by Cangi and Daly (2013) found that the use of a token economy increased socially appropriate behaviors and reduced inappropriate behaviors in a group of autistic schoolchildren. Autistic children are prone to disruptive behaviors such as pinching and hitting. When children in the study behaved appropriately (no hitting or pinching), they received a "steady hand" signal. If they hit or pinched, they lost a token. Children could then exchange specified amounts of tokens for minutes of play.

DAILY CONNECTION Behavior Modification in Children Parents and teachers often use behavior modification to change a child's behavior. Behavior modification uses the principles of operant conditioning to achieve behavioral change so that undesirable behaviors are replaced with socially acceptable ones. Some teachers and parents create a sticky card listing various behaviors (Figure 6.11). Sticker charts are a form of token savings as described in the text. Each time the children perform the behavior they receive a sticker and after a certain number of stickers they receive a reward or reinforcement. The goal is to promote acceptable behavior and reduce misconduct. Remember, it's better to reinforce desired behaviors rather than punish them. In the classroom, the teacher can reinforce a wide range of behaviors, from students raising their hands to silently walking down the hall to turning in homework. At home, parents can create a behavior chart that rewards children for things like putting

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Put away toys, brush teeth and help with dinner. For behavior change to be effective, reinforcement must be related to the behavior; reinforcement must be important to the child and consistent.

Figure 6.11: Sticker charts are a form of positive reinforcement and a behavior change tool. Once this little girl earns a certain number of stickers for desired behavior, she will be rewarded with a visit to the Ice Cream Shop. (Photo Credit: Abigail Batchelder) Timeout is another popular method of behavior modification in children. It works on the principle of negative punishment. When a child engages in undesirable behavior, he is excluded from the desired activity (Figure 6.12). Suppose Sophia and her brother Mario are playing with building blocks. Sophia throws some blocks at her brother, so you warn her that if she does it again, she'll lose time. A few minutes later, she throws more blocks at Mario. You remove Sophia from the room for a few minutes. When she comes back, she doesn't throw blocks. There are several important points to be aware of when planning to implement time-out as a behavior change technique. First, make sure the child is taken away from a desirable activity and placed in a less desirable location. If the activity is undesirable for the child, this technique will backfire as the child will be more comfortable being removed from the activity. Second, the length of downtime is important. The general rule is one minute for each year of the child's life. Sophia is five years old; so she's on a five minute break. Setting a timer helps kids know how long they need to sit during downtime. Finally, as a caregiver, there are some guidelines to keep in mind during time-out: remain calm when instructing your child to give time-out; Ignore your child during downtime (because caregiver attention can reinforce bad behavior) and give the child a hug or a kind word when the break is over.

Figure 6.12 Punishment is a popular form of negative punishment used by nurses. When a child misbehaves, he or she is removed from a desirable activity to reduce the undesirable behavior. For example (a) a child might be playing with friends on the playground and pushing another child; (b) the misbehaving child would then be removed from the activity for a short period of time. (Credit a: work modification by Simone Ramella; Credit b: work modification by JefferyTurner/Flickr)



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REINFORCEMENT SCHEMES Remember that the best way to teach a person or animal a behavior is to use positive reinforcement. For example, Skinner used positive reinforcement to teach rats to push a lever in a Skinner box. First, the mouse could randomly push the lever while exploring the box and a pellet of food would come out. What do you think the hungry mouse did after eating the pellet? He pressed the lever again and received another pellet of food. Each time the mouse pressed the lever, a ball of food came out. When an organism receives a reinforcer every time it exhibits a behavior, this is called continuous reinforcement. This reinforcement schedule is the fastest way to teach someone a behavior and is especially effective for training a new behavior. Let's remember the dog that learned to sit at the beginning of this chapter. Now you give him a treat every time he sits down. Timing is important here: you will be more successful if you present the reinforcer immediately after sitting so that he can make a connection between the target behavior (sitting down) and the consequence (getting a treat).

LINK TO LEARN Watch this video clip ( where veterinarian Dr. Sophia Yin shapes a dog's behavior using the steps outlined above.

Once a behavior is trained, researchers and trainers often turn to a different type of reinforcement schedule—partial reinforcement. In partial reinforcement, also known as intermittent reinforcement, the person or animal is not reinforced every time it performs the desired behavior. There are different types of partial reinforcement planes (Table 6.3). These schemes are described as fixed or variable and as ranges or ratios. Fixed refers to the number of responses between reinforcers, or the amount of time between reinforcers, which is fixed and unchanging. Variable refers to the number of responses or time between reinforcements that vary or change. Interval means the schedule is based on the time between reinforcers and Ratio means the schedule is based on the number of responses between reinforcers. reinforcement plans

reinforcement plan




halftime festivities

Booster is given at predictable time intervals (eg after 5, 10, 15 and 20 minutes).

Moderate response rate with significant pauses after reinforcement

Hospitalized patient uses doctor-timed, patient-controlled pain relief

Interval Variables

Reinforcements are delivered at unpredictable time intervals (for example, after 5, 7, 10, and 20 minutes).

Moderate but steady response rate

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reinforcement plans

reinforcement plan




constant ratio

Reinforcement is provided after a predictable number of responses (for example, after 2, 4, 6, and 8 responses).

High response rate with pauses after reinforcement

Piecework - factory workers who are paid for x number of items produced

variable ratio

Reinforcement is provided after an unpredictable number of responses (eg, after 1, 4, 5, and 9 responses).

High and steady response rate


Table 6.3

Now let's combine these four terms. A fixed-interval reinforcement schedule is when the behavior is rewarded after a set period of time. For example, June has major surgery at a hospital. She is expected to be in pain during her recovery and will need prescription medication for pain relief. June is given an intravenous drip with a patient-controlled pain reliever. Her doctor will set a limit: one dose per hour. June presses a button when the pain gets too bad and she is given a dose of medicine. Since the reward (pain relief) only occurs at a fixed interval, there is no point in exhibiting the behavior if it is not rewarded. With a variable interval reinforcement schedule, the person or animal receives reinforcement based on variable periods of time that cannot be predicted. Suppose Manuel is the manager of a fast food restaurant. Every once in a while someone from quality control comes into Manuel's restaurant. If the restaurant is clean and the service is fast, everyone on that shift earns a $20 bonus. Manuel never knows when the quality controller is going to show up, so he always tries to keep the restaurant clean and makes sure his team provides quick and efficient service. polite. His productivity in terms of fast service and clean restaurant is constant because he wants his team to earn the bonus. In a fixed-ratio schedule of reinforcement, there are a set number of responses that must occur before the behavior is rewarded. Carla sells glasses at an optician and earns a commission every time she sells a pair of glasses. She is always trying to sell people more glasses, including prescription glasses or a spare pair of glasses, so she can increase her commission. She doesn't care if the person really needs the prescription glasses, Carla just wants her bonus. The quality of what Carla sells does not matter, as her commission is not based on quality; it is based solely on the number of pairs sold. This energy quality distinction can help determine which method of reinforcement is best for a given situation. Fixed rates are more suitable for optimizing production quantity, while a fixed interval, where the reward is not quantified, can lead to higher quality production. In a variable-ratio reinforcement schedule, the number of responses required for a reward varies. This is the strongest partial reinforcement plan. An example of the variable ratio reinforcement schedule is gambling. Imagine Sarah - usually a smart, frugal woman - visiting Las Vegas for the first time. She's not a gambler, but out of curiosity she puts a coin in the slot machines and then another and another. Nothing happens. Two dollars and twenty-five cents later, her curiosity is waning and she's about to give up. But then the machine lights up, the bells ring, and Sarah gets 50 coins back. It's more like that! Sarah goes to insert coins with renewed interest, and a few minutes later she has used up all of her winnings and is down to $10 in the hole. Now might be a reasonable time to stop. And yet she keeps putting money into it


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at the slot machines because she never knows when the next backup will come. She keeps thinking that she could make $50 or $100 or even more in the next quarter. Since the winning table in most types of gambling has a variable ratio table, people keep trying and hoping that next time they will win big. This is one of the reasons why the game is so addictive - and so resistant to extinction. In operant conditioning, extinction of a reinforced behavior occurs some time after reinforcement ends, and the rate at which this occurs depends on the schedule of reinforcement. In a plane of varying proportion, the point of extinction occurs very slowly, as described above. But on other schedules of reinforcement, extinction can occur quickly. For example, if June pushes the painkiller button before the doctor approves the allotted time, no medication will be administered. It has a fixed-interval booster schedule (dosed hourly), so extinction occurs quickly if boosters don't come at the expected time. Among the reinforcement schedules, the variable ratio is the most productive and the most resistant to extinction. Fixed ranges are the least productive and the easiest to delete (Figure 6.13).

Figure 6.13 The four reinforcement schedules result in different response patterns. The variable ratio schedule is unpredictable, resulting in high and constant reaction rates with little or no post-reinforcement pause (e.g., players). A fixed-proportion schedule is predictable and results in a high response rate, with a short pause after reinforcement (eg, eyeglasses saleswoman). The variable interval schedule is unpredictable and results in a moderate and constant response rate (eg, restaurant manager). The fixed-interval schedule produces a clipped response pattern that reflects a significant pause after reinforcement (eg, surgical patient).

CONNECT THE CONCEPTS CONNECT THE CONCEPTS Gambling and the Brain Skinner (1953) stated, "If the gambling establishment cannot persuade a customer to hand over cash inconsiderately, it can achieve the same effect by taking a share of the customer's money." variable rate plan” (p. 397). Skinner uses the game as an example of the power and effectiveness of conditioning behaviors based on a variable-rate reinforcement schedule. In fact, Skinner was so confident in his knowledge of gambling addiction that he claimed he could turn a dove into a pathological gambler ("Skinner's Utopia," 1971). Aside from variable ratio gain power, gambling appears to affect the brain in the same way as some addictive drugs. The Illinois Institute for Addiction Recovery (n.d.) reports evidence suggesting that pathological gambling is an addiction similar to chemical addiction (Figure 6.14). In particular, gambling can activate the brain's reward centers, just like cocaine. Research has shown that some pathological gamblers have lower levels of the neurotransmitter (brain chemical) known as norepinephrine than normal gamblers (Roy, et al., 1988). According to a study conducted by Alec Roy and colleagues, norepinephrine is released when a person feels stressed, agitated or emotional; Pathological gamblers use gambling to increase their levels of this neurotransmitter. Another researcher, neuroscientist Hans Breiter, has done extensive research on gambling and its effects on the brain. Breiter (cited in Franzen, 2001) reports that “cash rewards produced in a game-like experiment

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Brain activation very similar to that observed in a cocaine addict receiving a cocaine infusion” (paragraph 1). A lack of serotonin (another neurotransmitter) can also contribute to compulsive behaviors, including compulsive gambling. It could be that the brains of pathological gamblers are different from those of other people, and perhaps this difference somehow led to gambling addiction, as these studies seem to suggest. However, it is very difficult to determine the cause, as it is impossible to conduct a real experiment (it would be unethical to try to turn randomly selected participants into problem gamblers). So it could be that causality is actually moving in the opposite direction – perhaps the act of gambling somehow alters the levels of neurotransmitters in some players' brains. It's also possible that an overlooked factor or confounding variable played a role in both gambling addiction and differences in brain chemistry.

Figure 6.14 Some research suggests that pathological gamblers use gambling to compensate for abnormally low levels of the stress-related hormone norepinephrine, which is released during times of excitement and excitement. (Image credit: Ted Murphy)

KNOWLEDGE AND LATENT LEARNING Although strict behaviorists like Skinner and Watson refused to believe that cognition (such as thoughts and expectations) plays a role in learning, another behaviorist, Edward C. Tolman, disagreed. Tolman's experiments with rats showed that organisms can learn without receiving immediate reinforcement (Tolman & Honzik, 1930; Tolman, Ritchie & Kalish, 1946). This finding was at odds with the then-dominant notion that reinforcement must be immediate for learning to occur, suggesting a cognitive aspect of learning. In experiments, Tolman put hungry rats through a maze without rewarding them for finding their way through the maze. He also studied a comparison group that was rewarded with food at the end of the maze. As unreinforced rats explored the maze, they developed a cognitive map: a mental image of the maze's layout (Figure 6.15). After 10 sessions in the maze without reinforcement, the food was placed in a target box at the end of the maze. Once the rats sensed the food, they ran through the maze just as quickly as the comparison group, which had been rewarded with food the entire time. This is called latent learning: learning that occurs but is not observable in behavior until there is a reason to demonstrate it.


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Figure 6.15 Psychologist Edward Tolman discovered that rats use cognitive maps to navigate a maze. Have you ever worked on different levels in a video game? You've learned when to turn left or right, go up or down. In this case, you relied on a cognitive map, like mice in a maze. (Source: Modification of the work by "FutUndBeidl"/Flickr)

Latent learning also occurs in humans. Children can learn by watching their parents' actions, but only demonstrate it later when what they have learned is needed. For example, suppose Ravi's father drives him to school every day. That's how Ravi learns his way from home to school, but he's never been there, so he hasn't had a chance to show he's learned the way. One morning, Ravi's father had to leave early for a meeting so he couldn't take Ravi to school. Instead, Ravi takes the same route on his bicycle that his father would have taken in the car. This shows latent learning. Ravi had learned his way to school, but he didn't have to prove that knowledge first.

DAILY CONNECTION This place is like a maze Ever got lost in a building and couldn't find your way out? While this can be frustrating, you're not alone. At some point we all get lost in places like museums, hospitals or university libraries. Whenever we go to a new place, we make a mental representation—or cognitive map—of the place, just as Tolman's rats made a cognitive map of their labyrinth. However, some buildings are confusing as they span too many areas that look the same or have short lines of sight. Because of this, it's often difficult to predict what's around the corner or decide whether to turn left or right to exit a building. Psychologist Laura Carlson (2010) suggests that what we fit into our cognitive map can affect our success in navigating cognitive structures.

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Proximity. She suggests paying attention to certain features when entering a building, such as a picture on the wall, a fountain, a statue or an escalator add information to our cognitive map that can be used later to find our way out of the building.

LINK TO LEARN Watch this video ( to learn more about Carlson's studies on cognitive maps and indoor navigation.

6.4 Observational learning (modeling) Learning objectives By the end of this section, you will be able to: • Define observational learning • Discuss the steps in the modeling process • Explain the prosocial and antisocial effects of observational learning Classical and operant conditioning, which are forms of associative learning. In observational learning, we learn by observing others and then mimicking or mimicking what they do or say. Individuals who perform the imitated behavior are called models. Research suggests that this imitative learning involves a specific type of neuron called a mirror neuron (Hickock, 2010; Rizzolatti, Fadiga, Fogassi & Gallese, 2002; Rizzolatti, Fogassi & Gallese, 2006). Humans and other animals are capable of learning by observation. As you will see, the expression "monkey see, monkey do" is indeed accurate (Figure 6.16). The same could be said about other animals. For example, in a study of social learning in chimpanzees, researchers gave juice boxes with straws to two groups of captive chimpanzees. The first group dipped the straw into the juice box and then sucked a small amount of juice from the end of the straw. The second group sucked straight through the straw and got a lot more juice. When the first group, the "dippers", observed the second group, "the suckers", what do you think happened? All "shells" in the first group switched directly to sucking through straws. By simply observing other chimpanzees and imitating their behavior, they learned that this was a more efficient method of obtaining sap (Yamamoto, Humle, and Tanaka, 2013).


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Figure 6.16 This spider monkey learned to drink water from a plastic bottle by seeing the behavior imitated by a human being. (Credit: US Air Force Senior Airman Kasey Close)

Imitation is much more obvious in humans, but is imitation really the sincerest form of flattery? Consider Claire's experience with observational learning. Claire's nine-year-old son, Jay, got into trouble at school and was defiant at home. Claire feared that Jay would end up like his brothers, two of whom were in prison. One day, after another bad day at school and another bad grade from the teacher, Claire, not knowing what to do, hit her son with a belt to make him behave. Later that night, as she was putting her children to bed, Claire saw her four-year-old daughter, Anna, grab a belt on her teddy bear and whip it. Claire was shocked to realize that Anna was impersonating her mother. Claire knew then that she wanted to discipline her children in other ways. Like Tolman, whose experiments on rats suggested a cognitive component to learning, psychologist Albert Bandura's ideas about learning differed from those of strict behaviorists. Bandura and other researchers have proposed a form of behaviorism called social learning theory, which takes cognitive processes into account. According to Bandura, pure behaviorism cannot explain why learning can occur without external reinforcement. He believed that internal mental states also played a role in learning and that observational learning involved much more than imitation. In imitation, a person simply copies what the model is doing. Observational learning is much more complex. According to Lefrançois (2012), there are several forms of observational learning: 1. You learn a new reaction. After seeing his colleague being ridiculed by his boss for coming

If you're going to be late, start leaving the house 10 minutes early so you're not late. 2. You decide whether or not you want to imitate the model based on what happened to the model.

Do you remember Julian and his father? Learning to surf, Julian was able to watch his father successfully surface on his board and then try to do the same. On the other hand, Julian might learn not to touch a hot stove after watching his father burn himself on the stove. 3. You will learn a general rule that you can apply to other situations.

Bandura identified three types of models: living, verbal and symbolic. A live model personally demonstrates the behavior when Ben stood up on his surfboard so Julian could see him doing it. A verbal instructional model does not demonstrate the behavior, but it explains or describes the behavior, much like a football coach telling his young players to kick the ball with the side of their foot, not their toe. A symbolic model can be fictional characters or real people demonstrating behaviors in books, movies, TV shows, video games, or Internet resources (Figure 6.17).

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Figure 6.17 (a) Yoga students learn through observation as their yoga teacher demonstrates correct posture and movement for their students (live model). (b) Models do not need to be present for learning to occur: through symbolic modeling, this child can learn a behavior by watching someone demonstrate it on television. (Credit a: Modification of work by Tony Cecala; Credit b: Modification of work by Andrew Hyde)

LINK TO LEARNING Latent learning and modeling are used constantly in the world of marketing and advertising. This commercial ( ran for months in the New York, New Jersey and Connecticut areas. Derek Jeter, an award-winning baseball player for the New York Yankees, promotes a Ford. The commercial aired in a part of the country where Jeter is an incredibly well-known athlete. He is wealthy and is considered to be very loyal and handsome. What message are advertisers sending when they show you in their ad? How effective do you think it is?

STEPS IN THE MODELING PROCESS Of course, we don't learn a behavior just by watching a model. Bandura described specific steps in the modeling process that must be followed for learning to be successful: attention, retention, reproduction, and motivation. First, you need to focus on what the model is doing - you need to pay attention to it. Next, you must be able to retain or recall what you observed; that's retention. Then you should be able to perform the behavior you observed and memorized; this is reproduction. Finally, you must have motivation. You must want to copy the behavior, and whether you're motivated or not depends on what happened to the model. Once you see the reinforced behavior model, you will be more motivated to copy them. This is called vicarious reinforcement. On the other hand, if you watched the model being punished, you would be less motivated to copy her. This is called vicarious punishment. For example, imagine four-year-old Allison watching her older sister Kaitlyn act out her mom's makeup, and then watching Kaitlyn take a break when her mom walked in. After her mom left the room, Allison was tempted to put on makeup but didn't want to take a break from her mom. What do you think she did? After you actually demonstrate the new behavior, the reinforcement you receive plays a role in whether or not you repeat the behavior. Bandura explored the modeling of behavior, particularly the childhood modeling of aggressive and violent adult behavior (Bandura, Ross & Ross, 1961). He conducted an experiment with a 5-foot-tall inflatable doll, which he dubbed the Bobo doll. In the experiment, the children's aggressive behavior was influenced by the fact that the teacher was punished for his behavior. In one scenario, a teacher aggressively handled the doll, hitting, throwing, and even hitting the doll while a child looked on. There were two types of children's reactions to the teacher's behavior. When the teacher was punished for her bad behavior, the children


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lessened her tendency to behave the way she used to. When the teacher was praised or ignored (rather than punished for her behavior), the children imitated what she did and even what she said. They punched, kicked and screamed at the doll.

LINK TO LEARN Watch this video clip ( to see part of the famous Bobo puppet experiment, including an interview with Albert Bandura.

What are the implications of this study? Bandura concluded that we watch and we learn, and that learning can have both prosocial and antisocial effects. Prosocial (positive) role models can be used to encourage socially acceptable behavior. Parents, in particular, should take note of this discovery. If you want your children to read, read to them. Let her see you reading. Keep the books in your home. Talk about your favorite books. If you want your children to be healthy, let them see that you eat well, exercise, and spend time together in fitness activities. The same goes for qualities like friendliness, politeness, and honesty. The main idea is that children watch and learn from their parents, even their parents' morals, so be consistent and throw out the old adage "do as I say, not as I do" because children tend to copying what you do instead of doing what you say. In addition to parents, many public figures such as Martin Luther King Jr. and Mahatma Gandhi, are considered pro-social role models capable of inspiring global social change. Can you think of anyone who has been a prosocial role model in their life? The antisocial effects of observational learning are also worth mentioning. As you saw in Claire's example at the beginning of this section, her daughter saw Claire's aggressive behavior and copied it. Research suggests this may help explain why abused children often become bullies (Murrell, Christoff & Henning, 2007). In fact, about 30% of abused children become abusive parents (US Department of Health and Human Services, 2013). We tend to do what we know. Abused children, who see their parents dealing with anger and frustration through violent and aggressive actions, often learn how to behave. Unfortunately, it's a vicious circle that's hard to break. Some studies suggest that violent TV shows, movies, and video games can also have antisocial effects (Figure 6.18), although more research is needed to understand the correlative and causal aspects of violence and media behavior. Some studies have found an association between children's perceptions of violence and aggression (Anderson & Gentile, 2008; Kirsch, 2010; Miller, Grabell, Thomas, Bermann, & Graham-Bermann, 2012). These results are perhaps not surprising, given that a child graduating from high school was exposed to approximately 200,000 acts of violence, including murder, robbery, torture, bombing, beating, and rape through various forms of media (Huston et al., 1992). Not only can seeing violence in the media influence aggressive behavior, teaching people how to behave in real-life situations, but it has also been suggested that repeated exposure to acts of violence also desensitizes people. Psychologists are working to understand this dynamic.

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Figure 6.18 Can video games make us violent? Psychological researchers deal with this topic. (Image credit: "woodleywonderworks"/Flickr)

LINK TO LEARN Watch this video ( to hear Brad Bushman, a psychologist who has published extensively on human aggression and violence, discuss his research.



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Key terms Acquisition phase of early learning in classical conditioning, in which a human or animal begins to associate a neutral stimulus and an unconditional stimulus in such a way that the neutral stimulus begins to elicit the conditioned response or events that occur together in the environment ( classical and operant conditioning) classical conditioning learning in which the stimulus or experience occurs before the behavior and is then paired with or associated with the behavior cognitive map mental image of the arrangement of the environment conditioned response (CR) Response elicited by the conditioned stimulus conditioned stimulus (CS) Stimulus that elicits a response because it is paired with an unconditional stimulus continuous reinforcement rewarding a behavior each time extinction occurs decrease in the conditioned response when the unconditional stimulus is no longer paired with the conditioned stimulus us fixed-interval reinforcement schedule the behavior is rewarded after a time specified fixed-ratio reinforcement schedule a defined number of responses that must occur before a behavior is rewarded (also second-order conditioning) using a conditioned stimulus to condition a neutral stimulus instinct unlearned knowledge that includes complex patterns of behavior; Instincts are thought to be more common in lower animals than humans, but latent learning does occur, but it may not be obvious until there is a reason to demonstrate that satisfying organism is repeated and repeated behaviors follow unpleasant consequences. learning is discouraged change in behavior or knowledge that is the result of the person experiencing model performing an exemplary behavior (in observational learning) negative punishment removing a pleasant stimulus to decrease or interrupt a behavior negative reinforcement removing an unwanted stimulus to increase a non-behavioral stimulus (NS) stimulus that initially elicits no response observational learning type of learning that occurs by observing other operant conditioning type of learning in which stimulus/experience after behavior occurs, reinforcing behavior only partially rewarding is shown at the moment

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Positive Punishment Adding an undesirable stimulus to stop or reduce a behavior Positive Reinforcement Adding a desirable stimulus to reinforce a behavior Primary reinforcer has innate reinforcing properties (e.g., food, water, shelter, sex) Punishment Implementing a consequence to decrease a behavior unlearned reflex, an organism's automatic response to a stimulus in the environment reinforcement implementing a consequence to reinforce a behavior secondary reinforcement has no intrinsic value by itself and only has value in conjunction with something else (e.g. money, gold stars) reinforcing properties, poker chips) Form Successively rewarding approach to a target behavior Spontaneous recovery Return of a previously extinguished conditioned response Stimulus discrimination Ability to respond differently to similar stimuli Stimulus generalization Demonstration of conditioned n Response to stimuli similar to conditioned stimulus unconditioned response (UCR) natural (unlearned) behavior to a given stimulus unconditioned stimulus (UCS) stimulus that elicits a reflexive response variable interval reinforcement schedule behavior is rewarded after unpredictable periods of time elapsed Variable ratio Schedule of reinforcement reinforcement The number of responses differs before the behavior occurs Rewarded vicarious punishment process in which the observer sees the model being punished, making the observer less likely to imitate the model's behavior

Summary 6.1 What is learning? Instincts and reflexes are innate behaviors - they occur naturally and do not involve learning. In contrast, learning is a change in behavior or knowledge that results from experience. There are three main types of learning: classical conditioning, operant conditioning and observational learning. Both classical and operant conditioning are forms of associative learning that involve making associations between events that occur together. Observational learning is exactly what it sounds like: learning by observing others. 6.2 Classical Conditioning Pavlov's pioneering work with dogs contributed significantly to what we know about learning. His experiments examined the type of associative learning we now call classical conditioning. In classical conditioning, organisms learn to associate recurring events, and researchers study how a reflex response to one stimulus can be mapped to another stimulus – training an association between the two stimuli. Pavlov's experiments show how stimulus-response linkages are formed. Watson, the founder of behaviorism, was heavily influenced by Pavlov's work. He tested humans by conditioning fear in a child named Little Albert. His results suggest that classical conditioning may explain how some fears work.


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develops. 6.3 Operant conditioning Operant conditioning is based on the work of B.F. Skinner. Operant conditioning is a form of learning in which the motivation for a behavior occurs after the behavior has been demonstrated. An animal or human receives a consequence after performing a certain behavior. The consequence is either a reinforcer or a punisher. Any reinforcement (positive or negative) increases the likelihood of a behavioral response. Any punishment (positive or negative) reduces the likelihood of a behavioral response. Different types of reinforcement schedules are used to reward behavior depending on a fixed or variable time period. 6.4 Observational Learning (Modeling) According to Bandura, learning can take place by observing others and then modeling what they do or say. This is called observational learning. There are certain steps in the modeling process that must be followed for learning to be successful. These steps include attention, retention, reproduction, and motivation. Through modeling, Bandura showed that children learn many things, good and bad, simply by watching their parents, siblings, and others.

Knowledge review 1. Which of the following is an example of a reflex that occurs at some point in a person's development? one. child riding a bicycle b. youth socialization c. Baby sucking a nipple d. Child walking 2. Learning is best defined as a relatively permanent change in behavior that ________. one. is congenital b. occurs as a result of experience c. occurs only in humans d. happens by watching others 3. Two forms of associative learning are ________ and ________. one. classical conditioning; operant conditioning b. classical conditioning; Pavlovian conditioning c. operant conditioning; observational learning d. operant conditioning; Learning Conditioning 4. In ________, the stimulus or experience occurs before the behavior and is then paired with the behavior. one. associative learning b. observational learning c. operant conditioning d. classical conditioning

5. A stimulus that initially produces no response in an organism is a ________. one. unconditional stimulus b. neutral stimulus c. conditioned stimulus d. Unconditional response 6. In Watson and Rayner's experiments, little Albert was conditioned to fear a white mouse and then began to fear other white furry objects. This shows ________. one. Higher Order Conditioning b. acquisition c. stimulus discrimination d. Stimulus generalization 7. Extinction occurs when ________. one. the conditioned stimulus is presented repeatedly without being paired with an unconditional stimulus b. the unconditional stimulus is presented repeatedly without being paired with a conditioned stimulus c. neutral stimulus is presented repeatedly without being paired with an unconditional stimulus d. Neutral stimulus is presented repeatedly without being paired with a conditioned stimulus

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8. In Pavlov's work with dogs, psychic secretions were ________. one. unconditional responses b. conditioned responses c. unconditional charms d. conditioned stimuli

13. The person who performs an exemplary behavior is called a ________. one. teacher b model c instructor D. Trainer

9. ________ is when you withdraw a pleasurable stimulus to interrupt a behavior. one. positive reinforcement b. negative reinforcement c. positive punishment d. negative punishment

14. In the study of the Bobo de Bandura doll, when children who observed the aggressive model were taken into a room with the doll and other toys, they ________. one. ignored the doll b. played well with the doll c. played with handmade toys d. kicked and threw the doll

10. Which of the following statements is not an example of a primary reinforcer? one. food b. money c. water D. Sex 11. The reward for successive approaches to a target behavior is ________. one. forms b. extinction c. positive reinforcement d. negative reinforcement 12. Slot machines reward players with money in what reinforcement scheme? one. fixed ratio b. variable ratio c. fixed range d. variable range

15. What is the correct order of steps in the modeling process? one. attention, memory, reproduction, motivation b. motivation, attention, reproduction, retention c. attention, motivation, retention, reproduction d. Motivation, attention, retention, reproduction 16. Who suggested observational learning? one. Ivan Pavlov born John Watson c. Albert Bandura the Younger B.F. Skinner

Critical Thinking Questions 17. Compare and contrast classical and operant conditioning. How are they similar? How are they different? 18. What is the difference between a reflex and a learned behavior? 19. If your mouth waters when your toaster opens toast, what are UCS, CS, and CR? 20. Explain how the processes of generalization and discrimination of stimuli are seen as opposites. 21. How does a neutral stimulus become a conditioned stimulus? 22. What is a Skinner box and what is it for?


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23. What is the difference between negative reinforcement and punishment? 24. What is shaping and how would you use shaping to teach a dog to roll over? 25. What is the effect of prosocial modeling and antisocial modeling? 26. Dude is 17 years old. Cara's mom and dad drink alcohol every night. They tell Cara that drinking is bad and that she shouldn't drink. Dude goes to a party where beer is served. What do you think Cara will do? Because?

Personal Application Questions 27. What is your personal definition of learning? How do your ideas about learning relate to the definition of learning presented in this text? 28. What kinds of things did you learn through the classical conditioning process? Operant conditioning? Learning by observation? how you learned them 29. Can you think of an example from your life of how classical conditioning produced a positive emotional response, such as happiness or enthusiasm? How about a negative emotional response like fear, anxiety, or anger? 30. Explain the difference between negative reinforcement and punishment, giving several examples of each based on your own experience. 31. Think of a behavior you would like to change. How can you use behavior modification, particularly positive reinforcement, to change your behavior? What is your positive reinforcer? 32. What did you learn after observing someone else?

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Chapter 7 | memory


Chapter 7


Figure 7.1 Photographs can trigger our memories and bring past experiences back to life. (Credit: Modification of work by Cory Zanker)

Chapter overview 7.1 How memory works 7.2 Parts of the brain involved in memory 7.3 Problems with memory 7.4 Ways to improve memory

Introduction We can be great learners, but if we don't have a way to store what we learn, what good is the knowledge we acquire? Take a few minutes to imagine what your day would be like if you couldn't remember anything you learned. You would have to figure out how to dress. What clothes should you wear and how do buttons and zippers work? You would need someone to teach you how to brush your teeth and tie your shoes. Who would you ask for help with these tasks, since you wouldn't recognize these people's faces in your home? Wait . 🇧🇷 🇧🇷 is this really your house? Uh oh, your stomach is starting to growl and you're hungry. You want to eat something, but you don't know where the food is stored or how to prepare it. Oh dear, this is getting confusing. Maybe it's better to go back to bed. A bed. 🇧🇷 🇧🇷 what is a bed We have incredible storage capacity, but how exactly do we process and store information? Are there different types of memory and, if so, what characterizes the different types? How exactly do we get our memories back? And why do we forget? This chapter will explore these questions as we learn about memory.


Chapter 7 | memory

7.1 How memory works Learning objectives By the end of this section you will be able to: • discuss the three basic functions of memory • describe the three stages of memory storage • describe and distinguish between procedural and declarative memory and semantic and episodic memory is a information processing system; For this reason, we often compare it to a computer. Memory is the set of processes used to encode, store, and retrieve information over different time periods (Figure 7.2).

Figure 7.2 Encoding is about getting information into the storage system. Storage is the holding of encrypted information. The third function is the retrieval or extraction of information from memory and back into consciousness.

LINK TO LEARN Watch this video ( to learn more about some unexpected facts about memory.

CODING We receive information into our brains through a process called encoding, which is the entry of information into the memory system. As soon as we receive sensory information from the environment, our brains label or encode it. We organize information with other similar information and connect new concepts with existing concepts. Encoding of information is done through automatic processing and laborious processing. Most likely, if someone asks you what you had for lunch today, you can easily remember this information. This is known as automatic processing or encoding of details such as time, space, frequency and meaning of words. Automatic processing usually occurs without conscious awareness. Remembering the last time you studied for an exam is another example of automatic processing. But what about the actual test material you studied? It probably required a lot of work and attention on your part to encrypt this information. This is called heavy processing (Figure 7.3).

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Figure 7.3 When you learn a new skill, like driving a car, you must make an effort and be careful to encode information about how to start the car, how to brake, how to turn, and so on. Once you learn to drive, you can automatically encode additional information about that skill. (Credit: Robert Couse-Baker)

What are the most effective ways to ensure that important memories are securely encrypted? Even a simple sentence is easier to remember when it makes sense (Anderson, 1984). Read the following sentences (Bransford & McCarrell, 1974), then turn your face and count backwards in 30s to zero, then try writing the sentences (don't look back at this page!). 1. The bills were sour because the seam was tearing. 2. The trip was not delayed because the bottle was broken. 3. The haystack was important because the cloth tore.

How good were you The statements you wrote were probably confusing and difficult to remember. Now try writing them again using the following prompts: bagpipes, ship name, and paratrooper. Then count backwards from 40 in fours and check how well you remembered the sentences this time. You can see that the sentences are much more memorable now because each one has been put into context. The material encodes much better if you make it meaningful. There are three types of encoding. The encoding of words and their meaning is called semantic encoding. It was first demonstrated by William Bousfield (1935) in an experiment in which he asked people to memorize words. The 60 words were actually grouped into 4 meaning categories, although the participants were unaware of this because the words were presented randomly. When asked to memorize the words, they tended to remember them in categories, showing that they were paying attention to the meaning of the words as they learned them. Visual coding is the coding of images, and auditory coding is the coding of sounds, especially words. To see how visual coding works, read this list of words: car, level, dog, truth, book, value. If you were later asked to recall the words on this list, which one do you think you would remember the most? You may find it easier to remember the words car, dog, and book, and harder to remember the words level, truth, and value. Why is this? For you can more easily remember pictures (mental images) than words alone. As you read the words car, dog, and book, you created pictures of these things in your mind. These are concrete and figurative words. On the other hand, abstract words like level, truth, and value are not very metaphorical words. Words rich in images are encoded visually and semantically (Paivio, 1986), building a stronger memory. Now let's move on to acoustic coding. You're driving your car and a song comes on the radio that you haven't heard in at least 10 years, but you sing along and remember every word. In the United States, children usually learn the alphabet through songs and learn the number of days in each month through rhymes: “Thirty days have September, / April, June and November; / Everyone has thirty-one, / except February, with twenty-eight days off, / and twenty-nine in all leap years.”


Chapter 7 | memory

easy to remember thanks to acoustic coding. We encode the sounds words make. That's one of the reasons why so much of what we teach young children is done through song, rhyme, and rhythm. Which of the three types of encoding do you think would give you the best recall of verbal information? A few years ago, psychologists Fergus Craik and Endel Tulving (1975) conducted a series of experiments to find out. Participants were given words along with questions about them. The questions asked participants to process the words at one of three levels. Visual processing issues included, among other things, the issue of letter fonts. Acoustic processing questions asked participants about the sound or rhyme of words, and semantic processing questions asked participants about the meaning of words. After participants were given the words and questions, they were given an unexpected memory or recognition task. Semantically coded words were remembered better than visually or acoustically coded words. Semantic coding involves a deeper level of processing than shallower visual or auditory coding. Craik and Tulving concluded that we process verbal information better through semantic encoding, particularly when we apply what is known as the self-reference effect. The self-reference effect is an individual's tendency to better remember information related to themselves compared to less personally relevant material (Rogers, Kuiper, & Kirker, 1977). Could you benefit from semantic coding when trying to memorize the concepts in this chapter?

STORAGE Once the information is encrypted, we need to store it somehow. Our brain takes the encrypted information and stores it. Storage is the creation of a permanent record of information. In order for a memory to be stored (i.e. long-term memory), it must go through three distinct stages: sensory memory, short-term memory, and finally long-term memory. These stages were first proposed by Richard Atkinson and Richard Shiffrin (1968). His model of human memory (Figure 7.4), called Atkinson-Shiffrin (A-S), is based on the belief that we process memories the same way a computer processes information.

Figure 7.4 According to the Atkinson-Shiffrin model of memory, information goes through three different stages before it is stored in long-term memory.

But A-S is just a memory model. Others, such as Baddeley and Hitch (1974), have proposed a model in which short-term memory itself takes different forms. In this model, storing memories in short-term memory is like opening different files on a computer and adding information. The type of short-term memory (or computer file) depends on the type of information received. There are memories in visuospatial form and memories of spoken or written material, and they are stored in three short-term systems: a visuospatial sketch pad, an episodic buffer, and a phonological loop. According to Baddeley and Hitch, a central executive part of memory oversees or controls the flow of information to and from memory.

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Chapter 7 | memory


three short-term systems.

Sensory memory In the Atkinson-Shiffrin model, environmental stimuli are first processed in sensory memory: storage of brief sensory events such as sights, sounds and tastes. It's a very short storage - even a few seconds. We are constantly bombarded with sensory information. We cannot absorb all, or even most of it. And most of it doesn't affect our lives. For example, what did your teacher wear to the last class? As long as the teacher was dressed appropriately, it didn't matter what she wore. We discard sensory information about sights, sounds, smells and even textures that we don't consider valuable information. When we see something as valuable, the information flashes into our short-term memory. A study of sensory memory examined the importance of valuable information in short-term memory storage. J.R. Stroop discovered a memory phenomenon in the 1930s: You'll name a color more easily if it appears printed in that color, which is called the Stroop effect. In other words, the word "red" is named faster, regardless of what color the word appears in, than any word colored in red. Do an experiment: name the colors of the words given to you in Figure 7.5. Don't read the words, but say the color the word is printed in. For example, if you see the word "yellow" written in green, you should say "green" not "yellow". This experiment is fun, but it's not as easy as it sounds.

Figure 7.5 The Stroop Effect describes why we have difficulty naming a color when the word and the color of the word are different.

Short-term memory Short-term memory (STM) is a temporary storage system that processes incoming sensory memory; it is sometimes called working memory. Short-term memory takes information from sensory memory and sometimes combines that memory with something already in long-term memory. Short-term memory lasts about 20 seconds. George Miller (1956), in his research on memory capacity, found that most people can retain about 7 items in the MTS. Some remember 5, others 9, so he called the STM's capacity 7 plus or minus 2. Think of short-term memory as the information you displayed on your computer screen - a document, spreadsheet or web page. Information moves from short-term memory to long-term memory (you save it to your hard drive) or is discarded (you delete a document or close a web browser). This practical step, the conscious repetition of information to be remembered to bring the STM into long-term memory, is called memory consolidation. You might be wondering, "How much information can our memory process at once?" to explore the


Chapter 7 | memory

Your short-term memory capacity and duration, ask a partner to read the random number lines (Figure 7.6) aloud to you, beginning each line with "Done?" and ending each by saying "Remember". At this point, you should try to write down the sequence of numbers from memory.

Figure 7.6 Using the memorization exercise discussed above, work with this sequence of numbers to determine the longest sequence of digits you can memorize.

Write the longest string where you hit the series. For most people, this will be close to 7, Miller's famous 7 plus or minus 2. Recall is slightly better for random numbers than for random letters (Jacobs, 1887) and also slightly better for information we hear (auditory encoding). than seeing (visual coding) (Anderson, 1969).

Long-term memory Long-term memory (LTM) is the continuous storage of information. Unlike short-term memory, there are no limits to the storage capacity of LTM. It includes everything you can remember that happened more than just a few minutes ago, to everything you can remember that happened days, weeks, and years ago. To use the computer analogy, the information on your LTM would be like the information you have stored on your hard drive. It's not on your desktop (your short-term memory), but you can access this information whenever you want, at least most of the time. Not all long-term memories are strong memories. Some reminders can only be accessed through command prompts. For example, you can easily remember one fact - "What is the capital of the United States?" - or a procedure - "How do you ride a bike?" - but may have trouble remembering the name of the restaurant remember where you had dinner when you were on holiday in France last summer. A prompt, e.g. For example, the fact that the restaurant is named after the owner, who spoke to you about their mutual interest in football, may help you remember the name of the restaurant. Long-term memory is divided into two types: explicit and implicit (Figure 7.7). Understanding the different types is important because a person's age or certain types of trauma or brain disorders can leave certain types of LTM intact while wreaking havoc on other types. Explicit memories are those that we remember and remember consciously. For example, if you are studying for a chemistry test, the material you are studying will be part of your explicit memory. (Note: Sometimes, but not always, the terms explicit memory and declarative memory are used interchangeably.) Implicit memories are memories that are not part of our conscious mind. They are memories formed from behaviors. Implicit memory is also known as non-declarative memory.

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Chapter 7 | memory


Figure 7.7 There are two components of long-term memory: explicit and implicit. Explicit memory includes both episodic and semantic memory. Implicit memory includes procedural memory and things learned through conditioning.

Procedural memory is a type of implicit memory: it stores information about how to do things. It is the memory for skillful actions, such as B. Brushing teeth, driving, swimming crawl (freestyle). By learning to swim freestyle, you'll practice swimming style: how to move your arms, how to turn your head to alternate breathing from side to side, and how to kick your legs. You would practice this many times until you get good at it. Once you learn to swim freestyle and your body knows how to move in the water, you'll never forget freestyle swimming, even if you haven't swam for a few decades. If you give a talented guitarist a guitar, he will still be able to play reasonably well long after he hasn't played. Declarative memory has to do with storing facts and events that we personally experience. Explicit (declarative) memory consists of two parts: semantic memory and episodic memory. Semantics means dealing with language and knowledge about language. An example would be the question “What does argumentative mean?” Knowledge about words, concepts, and language-based knowledge and facts is stored in our semantic memory. For example, the answers to the following questions are stored in your semantic memory: • Who was the first president of the United States? • What is democracy? • What is the longest river in the world?

Episodic memory is information about events that we personally experience. The concept of episodic memory was first proposed about 40 years ago (Tulving, 1972). Since then, Tulving and others have analyzed the scientific evidence and reformulated the theory. Currently, scholars believe that episodic memory is the recall of events in specific places at specific times, the what, where and when of an event (Tulving, 2002). It includes recall of visual images as well as a sense of familiarity (Hassabis & Maguire, 2007).


Chapter 7 | memory

DAILY CONNECTION Can you remember everything you've ever done or said? Episodic memories are also known as autobiographical memories. Let's quickly test your autobiographical memory. What were you wearing exactly five years ago today? What did you have for lunch on April 10, 2009? You may find it difficult, if not impossible, to answer these questions. Can you remember all the events you've experienced throughout your life - meals, conversations, choice of clothes, weather conditions and so on? Most likely none of us can remotely answer these questions; However, American actress Marilu Henner, best known for the TV show Taxi, might remember. She has an amazing and highly superior autobiographical memory (Figure 7.8).

Figure 7.8 Marilu Henner's autobiographical supermemory is known as hyperthymesia. (Photo Credit: Mark Richardson) Few people can remember events this way; Currently, only 12 known individuals have this ability and only a few have been studied (Parker, Cahill and McGaugh 2006). And although hyperthymesia usually occurs in adolescence, two children in the United States seem to have memories from well before their tenth birthday.

LINK TO LEARN Watch these video clips from Part 1 ( and Part 2 ( at the top autobiographical reminiscence subject of the 60 Minutes television news.

SUMMARY So you've worked hard to code (through extensive processing) and store some vital information for your next final exam. How do you retrieve this information from memory when you need it? The act of retrieving information from memory and bringing it back to consciousness is called retrieval. This is similar to locating and opening a previously saved document on your computer's hard drive. It is now back on your desktop and you can work with it again. Our ability to retrieve information from long-term memory is critical to our daily functioning. You need to be able to pull information from memory to do everything from brushing your hair and teeth, driving to work, knowing how to do your job when you get there. There are three ways to retrieve information from your long-term memory storage system: retrieval, recognition, and relearning. Recall is what we most often think of when we talk about memory retrieval: it means you can access information without any clues. For example, you would use Recall for a writing test. Recognition occurs when you identify information you learned earlier

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Chapter 7 | memory


again confronted him. It involves a comparison process. When you take a multiple-choice test, you have recognition to help you choose the correct answer. Here's another example. Let's say you graduated high school 10 years ago and moved back to your hometown for your 10th reunion. You may not remember all of your classmates, but you'll recognize many of them from their yearbook photos. The third form of recovery is relearning, and that's what it looks like. It's about learning information that you've previously learned. Whitney studied Spanish in high school, but after high school she didn't have the opportunity to speak Spanish. Whitney is now 31 years old and her company has offered her the opportunity to work in their Mexico City office. To prepare, she enrolls in a Spanish course at the local community center. She is amazed at how quickly she can pick up the language after not speaking it for 13 years; This is an example of relearning.

7.2 Parts of the brain involved in memory Learning objectives By the end of this section you will be able to: • explain the brain functions involved in memory • recognize the role of the hippocampus, amygdala and cerebellum Are memories stored in only one part? of the brain or are they stored in many different parts of the brain? Karl Lashley began researching this problem about 100 years ago by creating lesions in the brains of animals such as rats and monkeys. He looked for evidence of the engram: the group of neurons that serve as the "physical representation of memory" (Josselyn, 2010). First, Lashley (1950) trained rats to find their way through a maze. He then used the tools then available - in this case a soldering iron - to create lesions in the rat brains, particularly in the cerebral cortex. He did this because he was trying to erase the engram, or the original memory trace the rats had of the labyrinth. Lashley found no evidence of the engram, and the rats were still able to find their way through the maze regardless of the size or location of the lesion. Based on his generation of lesions and on the animals' response, he formulated the hypothesis of equipotentiality: if part of a brain area involved in memory is damaged, another part of the same area can assume this memory function (Lashley, 1950). Although Lashley's early work did not confirm the existence of the engram, modern psychologists are making progress in locating it. Eric Kandel, for example, has spent decades working on the synapse, the basic structure of the brain and its role in controlling the flow of information through neural circuits needed to store memories (Mayford, Siegelbaum, & Kandel, 2012). Many scientists believe that the entire brain is involved in memory. However, since Lashley's research, other scientists have been able to take a closer look at the brain and memory. They argued that memory is located in specific parts of the brain and specific neurons can be recognized for their involvement in memory formation. The main parts of the brain involved in memory are the amygdala, hippocampus, cerebellum, and prefrontal cortex (Figure 7.9).


Chapter 7 | memory

Figure 7.9 The amygdala is involved in fear and fear memories. The hippocampus is associated with declarative, episodic, and recognition memory. The cerebellum plays a role in processing procedural memories, e.g. B. How to play the piano. The prefrontal cortex appears to be involved in remembering semantic tasks.

THE AMYGDALA Let's first examine the role of the amygdala in memory formation. The main role of the amygdala is to regulate emotions such as fear and aggression (Figure 7.9). The amygdala plays a role in storing memories, as storage is affected by stress hormones. For example, one researcher experimented with mice and the fear response (Josselyn, 2010). Using Pavlovian conditioning, a neutral tone was associated with a footshock in the rats. This produced fear memory in the rats. After being conditioned, they froze each time they heard the sound (a defensive response in rats), indicating a memory of the shock to come. Next, the researchers induced cell death in neurons in the lateral amygdala, the specific area of ​​the brain responsible for fear memories. They found that the fear memory was gone (extinguished). Because of its role in processing emotional information, the amygdala is also involved in memory consolidation: the process of transferring new learning into long-term memory. The amygdala appears to facilitate the encoding of memories at a deeper level when the event is emotionally arousing.

LINK TO LEARN In this TED talk entitled “A mouse. A laser beam. A manipulated memory” ( Steve Ramirez and Xu Liu of MIT discuss the use of laser beams to manipulate fear memory in mice. Find out why his work sparked a media frenzy after being published in Science.

THE HIPPOCAMPUS Another group of researchers also experimented with mice to find out how the hippocampus works in memory processing (Figure 7.9). They created lesions in the rats' hippocampus and found that the rats exhibited memory impairment in various tasks, such as object recognition and maze walking. They concluded that the hippocampus is involved in memory, particularly normal recognition memory, as well as spatial memory (when memory tasks are such as recall tests) (Clark, Zola, & Squire, 2000). Another task of the hippocampus is to project information into cortical regions that give meaning to memories and connect them to other connected memories. It also plays a role in memory consolidation: the process of transferring new learning into long-term memory.

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Chapter 7 | memory


Violation of this area makes us unable to process new declarative memories. A famous patient, known for years only as H.M., had both his left and right temporal lobes (hippocampus) removed to help control the seizures he had suffered for years (Corkin, Amaral, González, Johnson, & Hyman, 1997). As a result, his declarative memory was severely impaired and he was unable to form new semantic knowledge. He lost the ability to form new memories, but he was still able to recall information and events that occurred prior to the operation.

LINK TO LEARN Watch this video ( about memory oddities to get a closer look at how memory works, and read more in this article (http: / ). HMbrain2) about the patient HM.

The Cerebellum and the Prefrontal Cortex Although the hippocampus appears to be more of an explicit memory processing area, you can still lose it and be able to create implicit memories (procedural memory, motor learning, and classical conditioning) thanks to your cerebellum ( Figure 7.9 ). For example, a classic conditioning experiment consists of training subjects to blink when they receive a puff of air. When researchers damaged the cerebellum of rabbits, they found that the rabbits were unable to learn the conditioned blink response (Steinmetz, 1999; Green & Woodruff-Pak, 2000). Other researchers have used brain scans, including positron emission tomography (PET) scans, to learn how people process and retain information. These studies indicate that the prefrontal cortex is involved. In one study, participants had to solve two different tasks: looking for the letter a in words (considered a perceptual task) or categorizing a noun as living or non-living (considered a semantic task) (Kapur et al., 1994). Participants were then asked which words they had previously seen. Recall was much better for the semantic task than for the perceptual task. According to PET scans, there was much more activation in the lower left prefrontal cortex on the semantic task. In another study, encoding was associated with left frontal activity, while information retrieval was associated with right frontal region (Craik et al., 1999).

NEUROTRANSMITTERS There also seem to be specific neurotransmitters involved in the memory process, such as epinephrine, dopamine, serotonin, glutamate, and acetylcholine (Myhrer, 2003). Researchers continue to argue and debate which neurotransmitter plays which specific role (Blockland, 1996). While we still don't know what role each neurotransmitter plays in memory, we do know that communication between neurons via neurotransmitters is critical to the development of new memories. Repeated activity of neurons leads to increased neurotransmitters at synapses and more efficient synaptic connections. This is how memory consolidation occurs. It is also believed that strong emotions trigger the formation of strong memories and weaker emotional experiences form weaker memories; this is called excitation theory (Christianson, 1992). For example, strong emotional experiences can trigger the release of neurotransmitters and hormones that improve memory; Therefore, our memory for an emotional event is generally better than our memory for a non-emotional event. When humans and animals are stressed, the brain secretes more of the neurotransmitter glutamate, which helps them remember the stressful event (McGaugh, 2003). This is clearly demonstrated by the so-called flashbulb memory phenomenon. A flash memory is an exceptionally clear memory of an important event (Figure 7.10). Where were you when you first heard about the 9/11 terrorist attacks? Most likely you can remember where


Chapter 7 | memory

you were and what you did. In fact, a Pew Research Center survey (2011) found that 97% of Americans age 8 and older at the time of the event can remember the moment they learned of the event, even a decade after it occurred.

Figure 7.10 Most people can remember where they were when they first heard about the 9/11 terrorist attacks. This is an example of flash memory: a recording of an unusual and unusual event that has very strong emotional associations. (Image credit: Michael Foran)

DIG DEEPER Inaccurate and false reminders Even flash reminders can become less accurate over time, even for very important events. For example, President George W. Bush answered incorrectly at least three times when asked how he learned about the 9/11 terrorist attacks. In January 2002, less than 4 months after the attacks, then-President Bush was asked how he found out about the attacks. He replied: I was sitting there, and my chief of staff - well, when we walked into the classroom, the first thing I saw was this plane going to the first building. There was a television on. And you know, I thought it was pilot error and I was amazed that anyone could make such a terrible mistake. (Greenberg, 2004, p. 2) Contrary to what President Bush recalled, nobody saw the first plane hit, except people on the ground near the Twin Towers. The first plane was not captured on video because it was a normal Tuesday morning in New York City when the first plane went down. Some people attributed Bush's failure to recognize the event to conspiracy theories. However, there is a much more benign explanation: human memory, even flash memories, can be weak. In fact, memory can be so poor that we can convince a person that an event happened to them even when it didn't. In studies, research participants remember hearing a word even though they never heard it. For example, participants were given a list of 15 sleep-related words, but the word "sleep" was not on the list. Participants remembered hearing the word "sleep" even though they had not actually heard it (Roediger & McDermott, 2000). The researchers who discovered this named the theory after themselves and a colleague, dubbing it the Deese-Roediger-McDermott paradigm.

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Chapter 7 | memory


7.3 Problems with memory Objectives By the end of this section you will be able to: • Compare and contrast the two types of amnesia • Discuss the unreliability of eyewitness testimony • Discuss coding errors • Discuss the various memory errors • Compare and contrast Amnesia Two Kinds of Interference You might be proud of your amazing ability to remember the birthdates and ages of all your friends and family, or you might remember vivid details of your 5th birthday party at Chuck E. Cheese's. However, we all feel frustrated and even embarrassed at times when our memories fail us. There are several reasons for this.

AMNESIA Amnesia is the loss of long-term memory that occurs as a result of illness, physical or psychological trauma. Psychologist Tulving (2002) and colleagues at the University of Toronto studied K.C. for years. KC suffered head trauma in a motorcycle accident and subsequently suffered severe amnesia. Tulving writes that what is remarkable about K.C. it is his complete inability to recall any event, circumstance or situation in his own life. His episodic amnesia spans his entire life, from birth to the present. The only exception is experiences he has had at any point in the last minute or two. (Tulving, 2002, p. 14)

Anterograde amnesia There are two common types of amnesia: anterograde amnesia and retrograde amnesia (Fig. 7.11). Anterograde amnesia is often caused by trauma to the brain, such as a blow to the head. With anterograde amnesia, you cannot remember new information, although you can remember information and events that happened before your injury. The hippocampus is usually affected (McLeod, 2011). This suggests that damage to the brain means that information cannot be transferred from short-term memory to long-term memory. that is, the inability to consolidate memories. Many people with this form of amnesia are unable to form new episodic or semantic memories, but are still able to form new procedural memories (Bayley & Squire, 2002). This was true for H.M., which was discussed earlier. The brain damage caused by his surgery resulted in anterograde amnesia. H.M. he read the same magazine over and over again without ever remembering having read it - it was always new to him. He also couldn't remember any people he met after the surgery. If you were introduced to H.M. and then left the room for a few minutes, when you came back he wouldn't recognize you and introduce himself to you again. However, when presented with the same puzzle several days in a row, even though he did not remember seeing the puzzle before, his speed of solving it became faster each day (due to relearning) (Corkin, 1965, 1968).


Chapter 7 | memory

Figure 7.11 This diagram illustrates the timeline of retrograde and anterograde amnesia. Memory problems that predate the injury and prevent retrieval of information previously stored in long-term memory is called retrograde amnesia. On the other hand, memory problems that extend from the moment of the injury and prevent the formation of new memories are called anterograde amnesia.

Retrograde Amnesia Retrograde amnesia is a loss of memory for events that occurred before the trauma. People with retrograde amnesia cannot remember part or all of their past. You have difficulty recalling episodic memories. What if one day you woke up in the hospital and there were people around your bed claiming to be your wife, your children and your parents? The problem is that you don't recognize any of them. You've been in a car accident, you've suffered a head injury, and now you have retrograde amnesia. You don't remember anything about your life before waking up in the hospital. This may sound like Hollywood movies, and Hollywood has been fascinated by the amnesia conspiracy for nearly a century, from the 1915 film Garden of Lies to more recent films like Jason Bourne's spy thrillers. However, for real-life patients with retrograde amnesia, like former NFL football player Scott Bolzan, the story is not a Hollywood movie. Bolzan fell, hit his head and destroyed 46 years of his life in one fell swoop. He now lives with one of the most extreme cases of retrograde amnesia in existence.

LINK TO LEARN Watch the video story ( detailing Scott Bolzan's amnesia and his attempts to regain his life.

MEMORY CONSTRUCTION AND RECONSTRUCTION Sometimes the making of new memories is called construction, and the process of bringing out old memories is called reconstruction. But when we recall our memories, we also tend to alter and modify them. A memory that is pulled from long-term storage into short-term memory is flexible. New events can be added and we can change what we think we remember about past events, leading to inaccuracies and distortions. Humans may not intend to distort the facts, but this can happen when old memories are retrieved and combined with new memories (Roediger and DeSoto, in press).

Suggestibility When someone witnesses a crime, that person's recall of the details of the crime is very important in capturing the suspect. Because memory is so fragile, the problem of suggestibility can easily (and often inadvertently) mislead witnesses. Suggestibility describes the effects of misinformation from outside sources that lead to the creation of false memories. In the fall of 2002, a sniper in the DC area shot people at a gas station exiting Home Depot and walking down the street. These attacks lasted over three weeks in various locations and resulted in the deaths of ten people. As you can imagine, during this period people were too afraid to leave their homes, go shopping or even walk around the neighborhoods. Law enforcement officers and the FBI worked hard to solve the crimes, and a whistleblower hotline was set up. Law enforcement agencies received more than 140,000 leads, leading to approximately 35,000 possible suspects (Newseum, undated).

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Most of the tips were dead ends until a white van was spotted at the scene of one of the shootings. The police chief went on national television with a photo of the white van. After the press conference, several other witnesses called to say they also saw a white van fleeing the scene of the shooting. At that time, there were over 70,000 white vans in the area. Both the police and the general public focused almost exclusively on the white vans because they believed the eyewitnesses. Other hints were ignored. When the suspects were finally apprehended, they were driving a blue sedan. As this example shows, we are vulnerable to the power of suggestion simply based on something we see on the news. Or we can claim that we remember something that is actually just a suggestion made by someone else. It is the suggestion that is the cause of the false memory.

Misidentification of Eyewitnesses While the memory and reconstruction process can be fragile, police, prosecutors, and courts often rely on the identification and testimony of eyewitnesses to prosecute criminals. However, misidentification and eyewitness testimony can lead to false convictions (Figure 7.12).

Figure 7.12 In examining cases where DNA evidence has cleared people of crimes, the Innocence Project has found that misidentification of eyewitnesses is the leading cause of false convictions (Benjamin N. Cardozo School of Law, Yeshiva University, 2009).

How does this happen? In 1984, Jennifer Thompson, then a 22-year-old college student in North Carolina, was brutally raped at knifepoint. While she was raped, she tried to memorize every detail of her rapist's face and physical features, vowing that if she survived, she would help him convict him. After police were contacted, a composite sketch of the suspect was made and six photos were shown to Jennifer. She chose two, one of which was Ronald Cotton. After looking at the photos for four to five minutes, she said, "Yeah. That's the one," and then she added, "I think that's the guy." When the detective questioned this, the detective asked, "Are you sure? Positive?" She said yes. She then asked the detective if she was all right, and he reinforced his decision by saying that she had done very well. These types of unintentional hints and tips from law enforcement officers can lead witnesses to identify the wrong suspect. The prosecutor was concerned about her lack of certainty the first time, so she looked at a line of seven men. She said she was trying to decide between number 4 and number 5 and finally decided that Cotton, number 5, "looks more like him. He was 22. When the trial began, Jennifer Thompson was in no doubt that she had been raped by Ronald.


Chapter 7 | memory

Cotton. She testified at the court hearing and her testimony was strong enough to help convict him. How did she go from "I think it's that guy" and "It looks more like him" to being so sure? Gary Wells and Deah Quinlivan (2009) argue that it is suggestive police identification procedures such as B. Stack the statements to single out the defendant, telling the witness which person to identify, and confirming the witness's choice by telling him "Good choice" or " You chose". the guy." After Cotton was convicted of rape, he was sentenced to life in prison plus 50 years. After 4 years in prison, he got a new trial. Jennifer Thompson testified against him again. This time, Ronald Cotton was sentenced to two life sentences After 11 years in prison, DNA evidence finally showed that Ronald Cotton did not commit the rape, was innocent and had been in prison for over a decade for a crime he did not commit.

LINK TO LEARN To learn more about Ronald Cotton and the fallibility of memory, watch these excellent videos from Part 1 ( and Part 2 ( l /Cotton2 ) around 60 minutes.

Sadly, Ronald Cotton's story is not unique. There are also people who were found guilty and placed on death row who were later exonerated. The Innocence Project is a non-profit group dedicated to exonerating the wrongfully convicted, including those convicted through eyewitness testimony. To learn more, you can visit

GOING FURTHER Preserving Eyewitness Memories: The Elizabeth Smart Case Compare the Cotton case with what happened in the Elizabeth Smart case. When Elizabeth was 14 and fast asleep in her bed at home, she was kidnapped at the point of a knife. Her nine-year-old sister, Mary Katherine, slept in the same bed and watched in horror as her beloved older sister was kidnapped. Mary Katherine was the only eyewitness to this crime and she was very scared. In the weeks that followed, the Salt Lake City Police Department and the FBI proceeded cautiously with Mary Katherine. They didn't want to implant false memories in her or deceive her in any way. They did not show her police statements or pressure her to make a composite sketch of the kidnapper. They knew that if memories of her corrupted, Elizabeth might never be found. For several months there was little or no progress in the case. Then, about 4 months after the kidnapping, Mary Katherine first remembered hearing the kidnapper's voice before that night (he had previously worked as a handyman in the family home), and then she was able to name the person who was the voice. The family contacted the press and others recognized him - after a total of nine months, the suspect was captured and Elizabeth Smart was returned to the family.

The Misinformation Effect Cognitive psychologist Elizabeth Loftus has done extensive research on memory. She examined false memories and recovered memories of childhood sexual abuse. Loftus also developed the misinformation effect paradigm, which states that after exposure to incorrect information, a person can remember the original event. According to Loftus, an eyewitness' memory of an event is very flexible because of the misinformation effect. To test this theory, Loftus and John Palmer (1974) asked 45 American college students to estimate the speed of cars using different question forms (Figure 7.13). Participants watched movies of car accidents

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and were asked to play the role of eyewitnesses and describe what happened. They were asked, “Approximately how fast were the cars going when they were (crushed, collided, pushed, crashed, touched)?” Participants estimated the speed of the cars based on the verb used. Participants who heard the word "broken" estimated that the cars were traveling at a much higher speed than participants who heard the word "touched". The implicit indication of speed, based on the verb heard, affected the participants' memory of the accident. At a follow-up visit a week later, participants were asked if they had seen broken glass (none was visible in the accident photos). Participants who were in the "shattered" group were twice as likely to say they remembered seeing glass. Loftus and Palmer showed that a guiding question encouraged them not only to remember seeing cars go faster, but also to falsely remember seeing broken glass.

Figure 7.13 When people are asked about an event, their memory of the event may change. (Credit to: Modification of work by Rob Young)

Controversies Over Repressed and Recovered Memories Other researchers have described how entire events, not just words, can be falsely remembered even when they didn't happen. The idea that memories of traumatic events can be suppressed has been a topic in the field of psychology since Sigmund Freud, and the controversy surrounding this idea continues to this day. Remembering false autobiographical memories is called false memory syndrome. This syndrome has received a lot of publicity, particularly with regard to memories of events for which there are no independent witnesses - often the only witnesses to the abuse are the perpetrator and the victim (eg, sexual abuse). On one side of the debate are those who have recovered memories years after child abuse. These researchers argue that some children's experiences have been so traumatizing and distressing that they must lock away these memories in order to have any semblance of a normal life. They believe that repressed memories can be locked away for decades and then retrieved intact through hypnosis and guided imagery techniques (Devilly, 2007). Research suggests that it is quite common for adults to have no memory of childhood sexual abuse. For example, a large study by John Briere and Jon Conte (1993) found that 59% of 450 men and women treated for sexual abuse before age 18 had forgotten their experiences. Ross Cheit (2007) suggested that repression of these memories in adulthood led to psychological distress. The Recovered Memory Project was created to allow victims of childhood sexual abuse to recall these memories and begin the healing process (Cheit, 2007;


Chapter 7 | memory

Devil, 2007). On the other hand, Loftus challenged the idea that people suppress memories of traumatic childhood events, including sexual abuse, and can recover those memories years later through therapeutic techniques such as hypnosis, guided visualization and age regression. Loftus isn't saying that childhood sexual abuse doesn't happen, but she questions whether or not these memories are accurate, and she is skeptical of the interrogation process used to access these memories, given that even the slightest suggestion by therapists can lead to disinformation effects. For example, researchers Stephen Ceci and Maggie Brucks (1993, 1995) asked three-year-olds to use an anatomically correct dummy to show where their pediatrician had touched them during an examination. Fifty-five percent of the children pointed to the dolls' genital/anal area, even if they had not had any genital examinations. Ever since Loftus published his first studies on the suggestibility of testimony in the 1970s, social scientists, police officers, therapists and lawyers have been aware of the flaws in interviewing practice. Consequently, measures were taken to reduce the suggestibility of witnesses. One way is to change the way witnesses are questioned. When interviewers use neutral and less incisive language, children better remember what happened and who was involved (Goodman, 2006; Pipe, 1996; Pipe, Lamb, Orbach, & Esplin, 2004). Another change concerns the way police lineups are conducted. It is recommended to use a constellation of blind photos. That way, the person managing the lineup doesn't know which photo belongs to the suspect, minimizing the opportunity to provide important clues. In addition, judges in some states are now informing juries of the possibility of misidentification. Judges can also suppress eyewitness testimony if they feel they are unreliable.

FORGOTTEN "I have a great memory to forget," joked Robert Louis Stevenson. Forgetting refers to the loss of information from long-term memory. We all forget things like a loved one's birthday, someone's name, or where we put our car keys. As you've seen, memory is fragile and forgetting can be frustrating and even embarrassing. But why do we forget? To answer this question, we will consider different perspectives on forgetting.

Coding error Sometimes memory leaks occur before the save process starts, which is a coding error. We cannot remember something if we have never stored it in our memory. That would be like trying to find a book on your e-reader that you've never purchased and downloaded. Often, to remember something, we have to pay attention to details and actively work to process the information (elaborate encoding). Not often. For example, think about how many times in your life you've seen a coin. Can you remember exactly what the front of a US penny looks like? When researchers Raymond Nickerson and Marilyn Adams (1979) asked this question, they found that most Americans don't know what it is. The reason is probably a coding error. Most of us never encode the penny details. We only encrypt enough information to distinguish it from other currencies. If we don't encode the information, it's not in our long-term memory, so we can't remember it.

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Figure 7.14 Can you tell which currency (a), (b), (c) or (d) is an exact representation of a US currency? The correct answer is (c).

Memory Errors Psychologist Daniel Schachter (2001), a well-known memory researcher, offers seven ways in which our memories fail us. He calls them the seven sins of memory and classifies them into three groups: forgetting, distorting, and intruding (Table 7.1). Schachter: Seven sins of remembering







Memory accessibility decreases over time

Forget events that happened a long time ago



forgotten by inattention

Forget where your phone is



Access to information is temporarily blocked

on the tip of the tongue

Incorrect attribution


Memory source is confused

Retrieving a dream memory as a waking memory



false memories

Result of the main questions



Memories distorted by the current belief system

Align memories with current beliefs



Inability to forget unwanted memories

traumatic events

Table 7.1

Let's look at the first sin of forgetting mistakes: impermanence, which means memories can fade over time. Here is an example of how this is done. Nathan's English teacher asked his students to read the novel To Kill a Mockingbird. Nathan comes home from school and tells his mother that he needs to read this book for class. "Oh, I loved that book!" she says. Nathan asks her what the book is about, and after some hesitation, she says, “Well. 🇧🇷 🇧🇷 I know I read the book in high school and I remember one of the main characters being named Scout and her father being a lawyer, but to be honest I can't remember anything else.” Nathan wonders if his mother actually read the book and his mother is surprised that she cannot remember the plot. What is happening here is memory deterioration: unused information tends to disappear over time.


Chapter 7 | memory

In 1885, the German psychologist Hermann Ebbinghaus analyzed the memorization process. First he memorized lists of nonsense syllables. He then measured how much he learned (retained) as he tried to relearn each list. He tested himself in various time periods, from 20 minutes later to 30 days later. The result is his famous forgetting curve (Figure 7.15). Due to memory deterioration, an average person loses 50% of stored information after 20 minutes and 70% of information after 24 hours (Ebbinghaus, 1885/1964). Your memory for new information rapidly decreases and eventually stabilizes.

Figure 7.15 The Ebbinghaus forgetting curve shows how quickly memory for new information fails.

Do you keep losing your cell phone? Have you ever driven home to make sure you turned off the stove? Have you ever walked into a room about something but forgotten what it was? You've probably answered yes to at least one, if not all, of these examples - but don't worry, you're not alone. We all tend to make the memory mistake known as distraction. These memory lapses are caused by interruptions in attention or our focus elsewhere. Cynthia, a psychologist, remembers a time when she recently made the distracted memory error. When I was taking court-ordered psychological tests, every time I went to court, I was given a temporary ID card with a magnetic stripe that would otherwise open locked doors. As you can imagine, that identity card is valuable and important in a court of law and nobody wanted it lost or picked up by a criminal. At the end of the day, I turned in my temporary ID. One day, when I was almost done with the assessment, my daughter's daycare called and said she was sick and needed to be picked up. It was flu season, I didn't know how sick she was and I was worried. I finished the assessment within the next ten minutes, packed up my tools, and hurried to my daughter's daycare. After picking up my daughter, I couldn't remember whether to return my ID or leave it on the table. I immediately called the court to verify this. Turns out I had my ID back. Why couldn't I remember this? (personal communication, September 5, 2013) When have you experienced distraction? "I was watching a movie called Oblivion and there was a famous actor in it. Oh, what's his name? He was in all these movies like The Shawshank Redemption and The Dark Knight Trilogy. I think he even won an Oscar. Oh God , I can picture your face and hear your distinctive voice, but I just can't think of your name! It's going to bother me until I remember it!" This particular error might look like this

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frustrating because you have the information at your fingertips. Have you ever tried this one? In that case, you've made the error known as blocking: you can't access the stored information (Figure 7.16).

Figure 7.16 Blocking is also known as the TOT phenomenon. The memory is right there, but you can't remember it any more than you can remember the name of this very famous actor, Morgan Freeman. (Credit: Modification of D. Miller's work)

Now let's take a look at the three errors of bias: misattribution, suggestibility, and bias. Misattribution occurs when you confuse the source of your information. Let's say Alejandro was with Lucia and they saw the first Hobbit movie together. So they split up and Alejandro watched the second Hobbit movie with someone else. Later that year, Alejandro and Lucia get back together. One day, they discuss how the Hobbit books and movies are different, and Alejandro tells Lucia, "I loved watching the second movie with you and watching you slide out of your chair during that super scary part. Look, Alejandro realized he had committed the misattribution error. What if someone is raped right after watching a TV show? Is it possible that the victim actually blames the person they saw on TV for the rape due to misattribution? This is exactly what happened to Donald Thomson. Australian eyewitness expert Donald Thomson appeared in a live TV discussion of the unreliability of eyewitness memory, he was later arrested, placed on a lineage and identified by a victim as the man who raped her. Police charged Thomson, although the rape took place while he was on television, they dismissed his alibi that he was in full view of a television audience and in the company of others. speakers, including a Deputy Commissioner of Police. 🇧🇷 🇧🇷 🇧🇷 Ultimately, investigators discovered that the rapist had attacked the woman while she was watching television - the same program Thomson was on. Authorities finally released Thomson. The woman mistook the rapist's face for the face she had seen on television. (Baddeley, 2004, p. 133) The second bias is suggestibility. Suggestibility is similar to misattribution in that it also involves false memories, but it is different. With misattribution, you create the false memory yourself, which is what the victim did in the Donald Thomson case above. It comes with suggestibility


Chapter 7 | memory

from someone else, for example B. a therapist or police interviewer who asks key questions of a witness during an interview. Memories can also be affected by distortion, which is the final distortion error. Schacter (2001) says that your feelings and your view of the world can actually distort your memory of past events. There are different types of prejudice: • Stereotypical prejudice includes racial and gender prejudice. For example, if Asian-American and

Given a list of names, European American survey participants were more likely to remember typical African American names associated with the basketball profession, such as Jamal and Tyrone, and more likely to remember typical white names, such as Greg and Howard, associated with the political profession (Payne, Jacoby & Lambert, 2004). • Egocentric bias involves enhancing our memories of the past (Payne et al., 2004). you really

Will you score the winning goal in this great soccer game or just assist? • Hindsight bias occurs when we think an outcome was inevitable in hindsight. This is the "I knew

it all the time” phenomenon. The reconstructive nature of memory contributes to hindsight bias (Carli, 1999). We remember false events that seem to confirm that we knew the outcome all along. Have you ever had a song playing over and over in your head? How about a reminder of a traumatic event you really don't want to think about? When you keep remembering something to the point where you can't "get it out of your mind" and it interferes with your ability to focus on other things, that's called persistence. It is Schacter's seventh and final memory error. It's actually a failure of our memory system, because we unwittingly recall unwanted memories, especially unpleasant ones (Figure 7.17). For example, you witness a terrible car accident on your way to work one morning and you can't concentrate on your work because you keep replaying the scene.

Figure 7.17 Many veterans of military conflicts unwittingly recall unwanted and unpleasant memories. (Photo credit: Department of Defense photo of US Air Force Technical Sgt. Michael R. Holzworth)

Interference Sometimes information is stored in our memory, but for some reason it is not accessible. This is called interference, and there are two types: proactive interference and retrospective interference (Figure 7.18). Have you ever gotten a new phone number or moved to a new address, but soon after gave people your old (and wrong) phone number or address? When the new year begins, do you find yourself accidentally writing down the previous year? These are examples of proactive interference: when old information prevents the retrieval of newly learned information. Backward interference occurs when more recently learned information interferes with retrieval of older information. For example, this week you will learn about Freud's psychoanalytic theory. Next week you will study the humanistic perspective of Maslow and Rogers. After that, you have a hard time remembering Freud's stages of psychosexual development because you can only remember Maslow's hierarchy of needs.

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Figure 7.18 Sometimes forgetting is caused by not retrieving information. This may be due to retrospective or proactive interventions.

7.4 Ways to improve memory Objectives By the end of this section, you will be able to: • Identify and apply strategies to improve memory. • Recognize and use effective study techniques We want to improve our memory so we don't forget where we left our car keys or, more importantly, what we need to know for a test. In this section, we'll look at some ways you can remember better and some strategies for learning more effectively.

STRATEGIES FOR IMPROVING MEMORY What are some everyday ways we can improve our memory, including recall? To ensure that information moves from short-term memory to long-term memory, you can use memory enhancement strategies. A strategy is the practice or conscious repetition of the information to be memorized (Craik & Watkins, 1973). Think about how you learned the tables as a child. You must remember that 6 x 6 = 36, 6 x 7 = 42 and 6 x 8 = 48. Memorizing these facts is an exercise. Another strategy is clustering: they organize information into manageable bits or blocks (Bodie, Powers, and Fitch-Hauser, 2006). Chunking is useful when trying to remember information like dates and phone numbers. Instead of trying to remember 5205550467, remember the number 520-555-0467. So if you met an interesting person at a party and you wanted to remember their phone number, of course you would separate them and repeat the number several times, which is the practical strategy.

LINK TO LEARN Try this fun activity ( that uses strategy to increase memory.


Chapter 7 | memory

You can also improve your memory using elaborative rehearsal: a technique that makes you think about the meaning of new information and its relationship to knowledge already stored in your memory (Tigner, 1999). In this case, you might remember, for example, that 520 is an Arizona area code and the person you met is from Arizona. This would help you better remember the 520 prefix. If the information is retained, it will move into long-term memory. Mnemonic devices are memory aids that help us organize information for encoding (Figure 7.19). They are particularly useful when we want to remember larger information such as steps, stages, phases and parts of a system (Bellezza, 1981). Brian needs to learn the order of the planets in the solar system, but he's having a hard time remembering the correct order. His friend Kelly suggests a memory device that might help him remember. Kelly tells Brian to just remember the name Mr. COMES J. SUN, and he can easily remember the correct order of the planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. You can use a memory device to remember a person's name, a mathematical formula, or the order of mathematical operations.

Figure 7.19 This is a mnemonic to help you remember the number of days in each month. The 31-day months are represented by the prominent knuckles and the shorter months fall between the knuckles. (Credit: Modification of work by Cory Zanker)

If you've ever watched the TV show Modern Family, you might have seen Phil Dunphy explain how he remembers names: I met a guy the other day named Carl. Well, I could forget that name, but he was wearing a Grateful Dead T-shirt. What is a band like the Grateful Dead? Phish. Where do fish live? The ocean. What else lives in the ocean? Coral. Hello Corel. (Wrubel & Spiller, 2010) It seems that the more vivid or unusual the mnemonic is, the easier it will be to remember. The key to using a mnemonic successfully is finding a strategy that works for you.

LINK TO LEARN Check out this fascinating presentation from TED Talks ( entitled Memory Skills Anyone Can Do. The talk will be given by Joshua Foer, a science writer who "accidentally" published the book in the US. He has won memory championships. He explains a memory device called the Memory Palace.

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Chapter 7 | memory


Some other strategies used to improve memory include expressive writing and words spoken aloud. Expressive writing helps strengthen your short-term memory, especially when you're writing about a traumatic experience in your life. Masao Yogo and Shuji Fujihara (2008) asked participants to write in 20-minute intervals several times a month. Participants were instructed to write about a traumatic experience, their best possible future self, or a trivial topic. The researchers found that this simple writing task increased short-term memory after five weeks, but only for participants who wrote about traumatic experiences. Psychologists can't explain why this writing task works, but it does. What if you want to remember items you need to pick up at the store? Just say them out loud. A number of studies (MacLeod, Gopie, Hourihan, Neary & Ozubko, 2010) found that saying a word aloud improves your memory for the word because it increases word distinctiveness. Feeling silly saying random foods out loud? This technique works just as well if you simply say the words. Using these techniques increased participants' memory for words by more than 10%. These techniques can also be used to help you study.

HOW TO LEARN EFFECTIVELY Based on the information in this chapter, here are some strategies and suggestions to help you refine your study skills (Figure 7.20). The key to each of these strategies is finding what works best for you.

Figure 7.20 Memory techniques can be useful in instructional learning. (Image credit: Barry Pousman)

• Use extensive repetition: In a famous article, Craik and Lockhart (1972) discussed their belief

The information we process most deeply ends up in long-term memory. His theory is called levels of processing. If we want to remember information, we must think about it more deeply and connect it to other information and memories to make it more meaningful. For example, if we try to remember that the hippocampus is involved in memory processing, we can imagine a hippopotamus with an excellent memory and then we can remember the hippocampus better. • Apply the self-reference effect: if you go through the extensive rehearsal process, this would be the case

be even more beneficial in making the material you are trying to memorize meaningful to you personally. So take advantage of the self-reference effect. Take notes in your own words. Write definitions from the text and then paraphrase them in your own words. Relate the material to something you learned in another class or think about how you can apply the concepts to your own life. By doing this, you build a web of retrieval cues to help you access the material when you need to remember it. • Don't forget the forgetting curve: as you know, what you learn sinks fast

Time. Even if you think you know the material, study it again just before exam time to improve.


Chapter 7 | memory

the probability that the information will stick in your memory. Superlearning can help prevent memory corruption. • Rehearsals, Rehearsals, Rehearsals: Review material over time in timed, organized learning

sessions. Organize and study your notes and take practice tests/exams. Link the new information to other information that you already know well. • Beware of Interference: To reduce the likelihood of interference, study during a quiet period.

no interruptions or distractions (like TV or music). • Keep moving: Of course you already know that exercise is good for your body, but did you also know

You know it's good for your mind too? Research suggests that regular aerobic exercise (anything that gets your heart rate up) is beneficial for memory (van Praag, 2008). Aerobic exercise promotes neurogenesis: the growth of new brain cells in the hippocampus, an area of ​​the brain known to play a role in memory and learning. • Get enough sleep: your brain keeps working while you sleep. The brain during sleep

organizes and consolidates information to be stored in long-term memory (Abel & Bäuml, 2013). • Use mnemonics: As you learned earlier in this chapter, mnemonics are often used

help us remember and recall information. There are different types of mnemonics, such as B. the acronym. An acronym is a word formed from the first letter of each of the words you want to remember. For example, even if you live near a lake, you might have trouble remembering the names of the five Great Lakes. What if I told you to think about the word Homes? HOMES is an acronym that stands for Huron, Ontario, Michigan, Erie and Superior: the Five Great Lakes. Another type of mnemonic is an acrostic: you form a sentence using all the first letters of words. For example, if you're taking a math test and you're having trouble remembering the order of operations, the following sentence will help: "Excuse me, dear Aunt Sally", because the order of math operations is parentheses, exponent, multiplication, division , addition, subtraction. There are also jingles, which are rhyming songs containing keywords related to the concept, such as: B. i before e, except after c.

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Chapter 7 | memory


Key Terms Distraction Memory lapses caused by attention deficit disorder or our focus on something else. Acoustic encoding Input of sounds, words, and music Amnesia Long-term memory loss that occurs as a result of illness, physical trauma, or psychological trauma Anterograde amnesia Memory loss for events that occur according to Brain Trauma Arousal Theory Strong emotions trigger o formation of strong and weaker emotional memories Experiences form weaker memories Atkinson-Shiffrin model (A-S) model of memory which states that we process information through three systems: sensory memory, short-term memory and long-term memory automatic processing affects the encoding of details of information such as time, space, frequency and the meaning of words such as feelings and worldview distorts the memory of past events and blocks memory errors that you do not have access to Stored information Grouping of information into bits or manageable blocks Building Formulating the new Memories Memory declarat Type of long-term memory of facts and events that we personally experience Laborious processing Encoding of information that requires effort and attention Thorough practice Thinking about the meaning of new information and its relationship to knowledge already stored in their memory Encoding of information input O memory system Engram Physical trace of memory Episodic memory Type of declarative memory that contains information about events we personally experience, also known as the equipotentiality hypothesis of autobiographical memory Some parts of the brain can take over parts damaged in the formation and storage of memories explicit memories we consciously try to recall and recover false memory syndrome false autobiographical memory memory flash memory exceptionally clear memory at an important event forgetting information loss of information from long-term memory implicit memories memories that do not levels of information processing become part of our consciousness t What is thought about more deeply becomes more meaningful and therefore better anchored in memory


Chapter 7 | memory

Long-term memory (LTM) Continuous storage of information Memory system or process that stores what is learned for future use Memory consolidation Active repetition to move information from short-term memory to long-term memory Strategy to improve memory Technique to ensure the transfer of information from short-term memory to long-term memory Memory mismatch errors, where you confuse the source of your information Misinformation effect paradigm, after being exposed to incorrect information, a person may remember incorrectly of the original event Mnemonics that help organize information for coding persistence Failure of the memory system that controls the involuntary retrieval of unwanted, especially uncomfortable memories proactive interference of old information makes it difficult to retrieve newly learned information procedural memory type of The memory for hab actions such as how to brush your teeth, how to drive a car and how to swim without access to information. Track recognition. Identify previously learned information after reencounter, usually in response to a cue reconstruction process that evokes old memories, which may be distorted by new information. Practice conscious repetition of information to be remembered Information is stored in long-term memory and returned to consciousness. Retroactive interference. More recently learned information makes retrieval of older information more difficult. retrograde amnesia. memory loss for events that occurred before the brain trauma for information relating to the self versus material that is less personally relevant semantic encoding entry of words and their meaning semantic memory declarative type of memory about words, concepts, and facts based on language and numbers memory Sensory Storage of brief sensory events such as sights, sounds, and tastes Short-term memory (STM) (also known as working memory) contains about seven bits of information before it is forgotten or stored, as well as information that has been retrieved and are used to create a permanent record of suggestibility of information effects of misinformation from external sources leading to the creation of false memories

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Chapter 7 | memory


Transient memory defect in which unused memories fade over time

Summary 7.1 How Memory Works Memory is a system or process that stores what is learned for future use. Our memory has three basic functions: encoding, storing and retrieving information. Encoding is the process of putting information into our memory system through automatic or elaborate processing. Storage is the preservation of information, and retrieval is the act of bringing information from storage into awareness through retrieval, recognition, and relearning. The idea that information is processed through three memory systems is called the Atkinson-Shiffrin (A-S) model of memory. First, environmental stimuli enter our sensory memory for periods ranging from less than a second to a few seconds. These stimuli that we perceive and pay attention to migrate to short-term memory (also called working memory). According to the A-S model, when we repeat this information, it is moved to long-term memory for permanent storage. Other models, such as Baddeley and Hitch, suggest that there is more of a feedback loop between short-term memory and long-term memory. Long-term memory has practically unlimited storage capacity and is divided into implicit and explicit memory. Finally, retrieval is the act of bringing memories out of storage and bringing them back into awareness. This happens through memory, recognition and relearning. 7.2 Parts of the brain involved in memory Since Karl Lashley, researchers and psychologists have looked for the engram, which is the physical trace of memory. Lashley did not find the engram, but he suggested that memories are distributed throughout the brain and are not stored in any specific area. We now know that three areas of the brain play a significant role in processing and storing different types of memories: the cerebellum, hippocampus and amygdala. The function of the cerebellum is to process procedural memories; new memories are encoded in the hippocampus; The amygdala helps determine which memories to store and plays a role in determining where memories are stored based on whether we have a strong or weak emotional response to the event. Strong emotional experiences can trigger the release of memory-enhancing neurotransmitters and hormones, so remembering an emotional event is generally stronger than remembering a non-emotional event. This is known as flash memory: our ability to remember significant life events. However, our memory for life events (autobiographical memory) is not always accurate. 7.3 Memory Problems We've all felt dismayed, frustrated and even ashamed when our memories failed. Our memories are flexible and prone to many errors, which is why eyewitness accounts have proven unreliable. There are several reasons why forgetfulness occurs. In cases of brain trauma or illness, the forgetfulness may be due to amnesia. Another reason we forget is a coding error. We cannot remember something if we have never stored it in our memory. Schacter presents seven memory errors that also contribute to forgetting. Sometimes information is actually stored in our memory but we cannot access it due to interference. Proactive interference occurs when old information interferes with the retrieval of newly learned information. Backward interference occurs when more recently learned information interferes with retrieval of older information. 7.4 Ways to Improve Memory There are many ways to combat the inevitable failures of our memory system. Some common strategies to use in everyday situations include reminders, rehearsals, self-reference, and getting enough sleep. The same strategies can also help you study more efficiently.


Chapter 7 | memory

Knowledge Review 1. ________ is another name for short term memory. one. sensory memory b. episodic memory c. working memory D. implicit memory 2. The storage capacity of long-term memory is ________. one. one or two bits of information b. seven bits, plus or minus two c. limited D. essentially unlimited 3. The three functions of memory are ________. one. automatic processing, complex processing and storage b. Encoding, processing and storage c. automatic processing, heavy processing and recovery d. Encoding, Storage, and Retrieval 4. This physical memory trait is known as ________. one. engram b. Lashley Effect c. Deese-Roediger-McDermott paradigm d. Instant Reminder Effect 5. A particularly clear reminder of an important event is a ________. one. engram b. excitation theory c. flash memory d. Equipotentiality hypothesis 6. ________ is when our memories of the past occur in a self-reinforcing way. one. stereotyped bias b. egocentric bias c. hindsight bias d. Enhancement bias 7. The tip of the tongue phenomenon is also known as ________. one. perseverance b. wrong task c. impermanence d. block

8. Sometimes the formulation of new memories is called ________ and the process of evoking old memories is called ________. one. Construction; reconstruction b. Reconstruction; construction c. Production; reproduction D. reproduction; Production 9. When learning to play the piano, the statement "All good boys play well" can help you remember the notes E, G, Bb, D, and F for the treble clef lines. This is an example of (a) ________. one. jingle b acronym c. acrostic d. acoustics 10. According to a study by Yogo and Fujihara (2008), if you want to improve your short-term memory, you should spend some time writing about ________. one. Your best possible future self b. a traumatic life experience c. a trivial topic d. Your shopping list 11. The self-reference effect refers to ________. one. Make the material you are trying to memorize meaningful to you personally b. form a sentence using all the first letters of the words you want to remember c. Form a word using the first letter of each of the words you are trying to remember. ie Words you want to remember to say out loud to yourself a. reminders b. memory improvement strategies c. detailed sample d. complex processing

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Critical Thinking Questions 13. Compare and contrast implicit and explicit memory. 14. Name and describe the three stages of memory using the Atkinson-Shiffrin model. 15. Compare and contrast the two ways of encoding information. 16. What can happen to your memory system if you suffer damage to your hippocampus? 17. Compare and differentiate the two types of disorders. 18. Compare and differentiate the two types of amnesia. 19. What is the self-reference effect and how can it help you study more efficiently? 20. You and your roommate spent all night studying for your psychology test. You think you know things; However, they suggest that you study again the next morning, an hour before the exam. Your roommate asks you to explain why you think this is a good idea. what do you say to her

Personal Application Questions 21. Describe something you learned that is now in your procedural memory. Discuss how you got this information. 22. Describe something you learned in high school that is now in your semantic memory. 23. Describe a flash memory of a significant event in your life. 24. Which of Schacter's seven memory errors did you make? Give an example of each. 25. Juries place a high value on the testimony of witnesses. Imagine that you are a lawyer representing a defendant accused of robbing a supermarket. Several eyewitnesses have been subpoenaed to testify against your client. What would you say to the jury about the credibility of a witness' testimony? 26. Create a mnemonic to help you remember a term or concept from this chapter. 27. What is an effective study technique you've used? How does it differ from the strategies suggested in this chapter?


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Chapter 8 | thought and intelligence


Chapter 8

thought and intelligence

Figure 8.1 Thinking is an important part of our human experience and one that has fascinated humans for centuries. Today it is a field of psychological studies. José Ferraz de Almeida Júnior's 19th-century Girl with a Book, August Rodin's 20th-century sculpture O Pensador, and Shi Ke's 10th-century painting Huike Thinking reflect the fascination with the thought process. human. (Center credit: Modification of work by Jason Rogers; Correct credit: Modification of work by Tang Zu-Ming)

Chapter Overview 8.1 What is cognition? 8.2 Language 8.3 Problem solving 8.4 What are intelligence and creativity? 8.5 Intelligence measures 8.6 The source of intelligence

Introduction Why is it so hard to break habits - like picking up the ringing phone when you shouldn't, eg. B. when driving a car? How does a person who has never seen or touched snow in real life develop an understanding of the concept of snow? How do young children acquire the ability to learn language without formal instruction? Psychologists who study thinking explore questions like these. Cognitive psychologists also study intelligence. What is intelligence and how does it differ from person to person? Are smart guys a type of intelligence, and if so, how do they relate to other types of intelligence? What does an IQ test actually measure? These and other questions will be explored in this chapter as you explore thinking and intelligence. In other chapters we have discussed the cognitive processes of perception, learning and memory. In this chapter, we focus on high-level cognitive processes. As part of this discussion, we will look at thinking and briefly examine the development and use of language. We'll also discuss problem solving and creativity before ending with a discussion of how intelligence is measured and how our biology and environment interact to affect intelligence. After completing this chapter, you will have a better appreciation of the higher-level cognitive processes that contribute to our distinctiveness as a species.


Chapter 8 | thought and intelligence

8.1 What is cognition? Learning Outcomes By the end of this section, you will be able to: • describe cognition • distinguish between concepts and prototypes • explain the difference between natural and artificial concepts Imagine all your thoughts as if they were physical entities moving rapidly in your mind whirl. How is it possible for the brain to move from one thought to the next in an organized and orderly way? The brain perceives, processes, plans, organizes and remembers endlessly - it is always active. However, you don't notice most of your brain's activity as you move about your daily routine. This is just one facet of complex cognitive processes. Simply put, cognition is thinking and encompasses the processes associated with perception, knowledge, problem solving, judgment, language, and memory. Cognitive scientists seek ways to understand how we integrate, organize, and use our conscious cognitive experiences without being aware of all the unconscious work our brains are doing (eg, Kahneman, 2011).

INSIGHT When you wake up every morning, you start thinking - you think about the tasks you have to do that day. In what order should you perform your tasks? Should you go to the bank, laundromat or supermarket first? Can you do these things before going to class or do they have to wait until after school is over? These thoughts are an example of cognition in action. Cognition is extraordinarily complex and an essential feature of human consciousness, but not all aspects of cognition are consciously experienced. Cognitive psychology is the field of psychology devoted to studying how people think. It attempts to explain how and why we think the way we do by examining the interactions between human thinking, emotions, creativity, language and problem solving, and other cognitive processes. Among other things, cognitive psychologists seek to identify different types of intelligence, measure why some people solve problems better than others, and how emotional intelligence affects success in the workplace. They also sometimes focus on how we organize thoughts and information we collect from our environment into meaningful thought categories, which will be discussed later.

CONCEPTS AND PROTOTYPES The human nervous system is capable of processing infinite flows of information. The senses serve as an interface between the mind and the external environment, capturing stimuli and translating them into nerve impulses that are sent to the brain. The brain then processes this information and uses the relevant parts to generate thoughts, which can be expressed through language or stored in memory for future use. To make this process even more complex, the brain doesn't just collect information from the external environment. In forming thoughts, the brain also extracts information from emotions and memories (Figure 8.2). Emotions and memories are powerful influences on our thoughts and behavior.

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Chapter 8 | thought and intelligence


Figure 8.2 Sensations and information are received by our brains, filtered through emotions and memories, and processed into thoughts.

To organize this incredible amount of information, the brain has developed a kind of filing cabinet in the head. The various files stored in the archive are called concepts. Concepts are categories or groupings of verbal information, images, ideas or memories, such as B. Life experiences. In many ways, concepts are big ideas generated by looking at details, categorizing, and combining those details into cognitive structures. You use concepts to see relationships between different elements of your experiences and to keep information organized and accessible in your mind. Concepts are informed by our semantic memory (you'll learn more about semantic memory in a later chapter) and are present in all aspects of our lives; However, concepts are more easily recognized in the classroom, where they are explicitly discussed. For example, if you study US history, you will learn more than just individual events that happened in America's past. You absorb a great deal of information by listening to and participating in discussions, examining maps, and reading first-hand accounts of people's lives. Your brain analyzes these details and develops a comprehensive understanding of American history. As you do, your brain collects details that inform and refine your understanding of related concepts such as democracy, power, and freedom. Concepts can be complex and abstract, like justice, or more concrete, like bird species. In psychology, for example, Piaget's stages of development are abstract concepts. Some concepts, like tolerance, are embraced by many people because they have been used in different ways over the years. Other concepts, like the characteristics of your ideal boyfriend or your family's birthday traditions, are personal and individualized. In this way, the concepts touch every aspect of our lives, from our many daily routines to the guiding principles of how government works. Another technique your brain uses to organize information is to identify prototypes for the concepts you develop. A prototype is the best example or representation of a concept. For example, for the civil disobedience category, your prototype might be Rosa Parks. His peaceful resistance to segregation on a city bus in Montgomery, Alabama is a visible example of civil disobedience. Or your prototype might be Mohandas Gandhi, sometimes called Mahatma Gandhi ("Mahatma" is an honorific) (Figure 8.3).


Chapter 8 | thought and intelligence

Figure 8.3 In 1930, Mohandas Gandhi led a group of peaceful protests against a British tax on salt in India.

Mohandas Gandhi served as the non-violent force for India's independence as he urged Buddhist, Hindu, Muslim and Christian leaders - Indian and British - to work together peacefully. Although he was not always able to avoid the violence around him, his life is an unshakable example of the prototype of civil disobedience (Foundation of Constitutional Rights, 2013). Just as concepts can be abstract or concrete, we can distinguish between concepts that are functions of our direct experience of the world and those that are more artificial in nature.

NATURAL AND ARTIFICIAL CONCEPTS In psychology, concepts can be divided into two categories, natural and artificial. Natural concepts arise “naturally” through their experiences and can be developed from direct or indirect experiences. For example, if you live in Essex Junction, Vermont, you've likely had a lot of first-hand experience with snow. You've seen it fall from the sky, you've seen the snow fall barely covering the windshield of your car, and you've shoveled 18 inches of fluffy white snow when you thought, "This is perfect for skiing." your best friend threw snowballs at you and sledded down the steepest hill in town. In short, you know snow. You know how it looks, smells, tastes and feels. However, if you've lived your entire life on the island of St. Vincent in the Caribbean may never have seen, let alone tasted, smelled or touched snow. You know snow through the indirect experience of seeing images of snow falling - or from movies where snow is part of the scenery. Either way, snow is a natural concept because you can develop an understanding of it through direct observation or experience with snow (Figure 8.4).

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Chapter 8 | thought and intelligence


Figure 8.4 (a) Our concept of snow is an example of a natural concept - one that we understand through direct observation and experience. (b) In contrast, artificial concepts are those we know by a certain set of properties they always exhibit, such as B. that which defines various basic forms. (Credit a: Modification of work by Maarten Takens; Credit b: Modification of work by "Shayan (USA)"/Flickr)

An artificial concept, on the other hand, is a concept defined by a specific set of features. Various properties of geometric shapes, such as squares and triangles, serve as useful examples of artificial concepts. A triangle always has three angles and three sides. A square always has four equal sides and four right angles. Mathematical formulas like the area equation (length x width) are artificial concepts defined by specific sets of features that are always the same. Artificial concepts can improve understanding of a topic by building on each other. For example, before learning the concept of "area of ​​a square" (and the formula for finding it), you need to understand what a square is. Once the concept of "area of ​​a square" is understood, an understanding of area for other geometric shapes can build on the original understanding of area. Using artificial concepts to define an idea is key to communicating with others and engaging in complex thinking. According to Goldstone and Kersten (2003), concepts act as building blocks and can be connected in countless combinations to form complex thoughts.

SCHEMES A schema is a mental construct consisting of a grouping or collection of related concepts (Bartlett, 1932). There are many different types of schemas, and they all have one thing in common: schemas are a method of organizing information that allows the brain to function more efficiently. When a schema is activated, the brain immediately makes assumptions about the person or object being observed. There are several types of schemes. A role schema makes assumptions about how individuals will behave in certain roles (Callero, 1994). For example, imagine you know someone who introduces himself as a firefighter. When this happens, your brain automatically switches to the "firefighter blueprint" and begins to assume that this person is brave, selfless, and community-oriented. Although you don't know this person, you've already made judgments about him without knowing it. Schemas also help fill in gaps in the information you receive from the world around you. While schematics allow for more efficient information processing, there can be problems with schematics whether or not they are correct: maybe that particular firefighter isn't brave, he just works as a fireman to pay the bills while studying to be a children's librarian. An event schema, also known as a cognitive script, is a set of behaviors that may seem routine. Think about what you are doing when you get on the elevator (Figure 8-5). First the doors open and you wait to let passengers out of the elevator. So you get on the elevator and turn towards the doors, looking for the right button to press. You never stand at the bottom of the elevator, do you? And when you're in a crowded elevator and you can't look straight ahead, it seems weird, doesn't it? Interestingly, event schemes can vary greatly between different cultures and countries. For example, while in the United States it is quite common to greet one another with a handshake, in Tibet it is greeted by sticking out the tongue, and in Belize it is with a closed fist (Cairns Regional Council,


Chapter 8 | thought and intelligence


Figure 8.5 What event schema do you run when riding in an elevator? (Image credit: Gideon/Flickr)

Since event schemes are automatic, they can be difficult to change. Imagine that you are walking home from work or school. This event scheme involves getting into the car, closing the door, and buckling the seat belt before putting the key in the ignition. You can run this script two or three times a day. As you drive home, you hear your phone ring. Typically, the event schema that occurs when you hear the phone ring involves locating the phone and answering the phone or replying to your last text message. So, without thinking, you reach for your phone, which can be in your pocket, pocket or on the passenger seat of the car. This powerful scheme of events is based on your behavioral pattern and the pleasurable stimulation that a call or text message gives your brain. Because it is a scheme, it is extremely challenging for us to stop answering the phone, knowing that by doing so we are putting our own lives and the lives of others at risk (Neyfakh, 2013) (Figure 8.6).

Figure 8.6 Texting while driving is dangerous, but it's a pattern of events that some people find difficult to resist.

Do you remember the elevator? It seems almost impossible to enter and not stand in front of the door. Our powerful event schema drives our behavior in the elevator, and our phones are no different. Recent research suggests that looking at your phone in many different situations is a habit or pattern of events, making it particularly difficult to refrain from looking while driving (Bayer & Campbell, 2012). As texting and driving have become dangerous epidemics in recent years, psychologists are looking for ways to help people break "phone time" while driving. These patterns of events are why many habits, once acquired, are difficult to break. As we examine thinking, remember how powerful the forces of concepts and schemas are in our understanding of the world.

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Chapter 8 | thought and intelligence


8.2 Language Learning Objectives By the end of this section, you will be able to: • define language and demonstrate familiarity with language components • understand how language usage evolves • explain the relationship between language and thinking Language is a communication system that includes the use of words and systematic rules for organizing those words to convey information from one person to another. Although language is a form of communication, not all communication is language. Many species communicate through their postures, movements, smells or sounds. This communication is critical for species that need to interact and form social relationships with their peers. However, many people claim that it is language that makes humans unique among all animal species (Corballis & Suddendorf, 2007; Tomasello & Rakoczy, 2003). This section is about what characterizes language as a special form of communication, how language use develops, and how language influences our thinking.

LANGUAGE COMPONENTS Language, whether spoken, written or written, has specific components: a lexicon and a grammar. Lexicon refers to the words of a specific language. Lexicon is the vocabulary of a language. Grammar refers to the set of rules used to convey meaning through the use of the lexicon (Fernández & Cairns, 2011). For example, English grammar dictates that most verbs end in “-ed” to indicate the past tense. Words are formed by combining the different phonemes that make up the language. A phoneme (for example, the sounds "ah" vs. "eh") is a basic sound unit of a given language, and different languages ​​have different sets of phonemes. Phonemes are combined into morphemes, which are the smallest linguistic units that convey some kind of meaning (for example, "I" is a phoneme and a morpheme). We use semantics and syntax to build the language. Semantics and syntax are part of the grammar of a language. Semantics refers to the process by which we derive meaning from morphemes and words. Syntax refers to the way words are organized into sentences (Chomsky, 1965; Fernández & Cairns, 2011). We apply grammar rules to organize the lexicon in new and creative ways, allowing us to convey information about concrete and abstract concepts. We can talk about our immediate and observable surroundings, as well as the surface of invisible planets. We can share our innermost thoughts and plans for the future and discuss the value of a college education. We can provide detailed instructions on how to prepare a meal, fix a car or start a fire. The flexibility that language offers to convey very different types of information is a property that makes it so unique as a means of communication between people.

LANGUAGE DEVELOPMENT Given the remarkable complexity of a language, mastering a language might be expected to be a particularly tedious task; In fact, for those of us trying to learn a second language as adults, this rings true. However, young children very quickly master the language with relative ease. B. F. Skinner (1957) proposed that language is learned by reinforcement. Noam Chomsky (1965) criticized this behaviorist approach, arguing instead that the mechanisms of language acquisition are biologically determined. Language use develops without formal instruction and appears to follow a very similar pattern among children from very different cultures and backgrounds. It seems, then, that we are born with a biological predisposition for language acquisition (Chomsky, 1965; Fernández & Cairns, 2011). Furthermore, there appears to be a critical phase for language acquisition.


Chapter 8 | thought and intelligence

so that this competence in language acquisition is maximum at the beginning of life; In general, the ease with which people acquire and master new languages ​​decreases with age (Johnson & Newport, 1989; Lenneberg, 1967; Singleton, 1995). Children learn language from a very early age (Table 8.1). In fact, this seems to be happening before we're even born. Newborns prefer their mother's voice and seem to be able to distinguish between her speech and other languages. Infants are also attuned to the languages ​​used around them and show a preference for videos of faces moving in sync with the sound of spoken language over videos out of sync with the sound (Blossom & Morgan, 2006; Pickens, 1994; Spelke & Cortelyou, 1981). Stages of language and communication development



language development and communication


0–3 fun

Reflective Communication


3–8 fun

Reflective Communication; interest in others


8–13 fun

intentional communication; conviviality


12–18 fun

first words


18–24 fun

Simple two word phrases


2-3 years

Phrases of three or more words


3-5 years

complicated sentences; have conversations

Table 8.1

DEEPENING THE CASE OF GENIUS In the fall of 1970, a social worker in the Los Angeles area encountered a 13-year-old girl growing up in extremely neglectful and abusive conditions. The girl who became known as the Genie spent most of her life tied to a chamber pot or tied to a bed in a small closed room with the curtains drawn. For just over a decade, Genie had virtually no social interaction and access to the outside world. Due to these circumstances, Genie was unable to stand up, chew solid food, or speak (Fromkin, Krashen, Curtiss, Rigler, & Rigler, 1974; Rymer, 1993). The police took Genie into protective custody. Genie's abilities improved dramatically after she was removed from her abusive environment, and early on, she seemed to acquire language—much later than predicted by the critical period hypotheses presented at the time (Fromkin et al., 1974). Genie managed to acquire an impressive vocabulary in a relatively short period of time. However, she never developed a mastery of the grammatical aspects of the language (Curtiss, 1981). Perhaps the lack of opportunity to learn a language at a critical stage prevented Genie from fully acquiring and using the language.

You must remember that each language has its own set of phonemes used to create morphemes, words, and so on. Babies can distinguish between the sounds that make up language (for example, they can tell the difference between the "s" in vision and the "ss" in fist); They can distinguish the sounds of all human languages ​​from scratch, even those that don't occur in the languages ​​used.

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Chapter 8 | thought and intelligence


its surroundings. From around 1 year of age, however, they can only distinguish between the phonemes used in the language or languages ​​in their environment (Jensen, 2011; Werker & Lalonde, 1988; Werker & Tees, 1984).

LINK TO LEARN Visit this website ( to learn more about how babies lose the ability to distinguish between all possible human phonemes as they age.

After the first few months, babies enter the so-called babbling phase, in which they tend to produce single syllables that are repeated over and over again. Over time, more variations appear in the syllables they produce. During this time, babies are unlikely to try to communicate; they are just as likely to chatter when alone as they are with loved ones (Fernández & Cairns, 2011). Interestingly, infants raised in environments where sign language is used also show babbling in their hand gestures at this stage (Petitto, Holowka, Sergio, Levy, & Ostry, 2004). In general, a child's first word is spoken sometime between the ages of 1 year and 18 months, and for months after that, the child remains in the "one word" stage of language development. During this time, children know a variety of words but produce only one-word utterances. The child's early vocabulary is limited to familiar objects or events, often nouns. Although children only make one-word expressions at this stage, these words often carry greater meaning (Fernández & Cairns, 2011). For example, a child who says "cookie" might identify a cookie or ask for a cookie. As a child's lexicon grows, he begins to pronounce simple sentences and acquire new vocabulary at a very rapid pace. In addition, children begin to demonstrate a clear understanding of the specific rules that apply to their language(s). The mistakes children sometimes make also show how well they understand these rules. This is sometimes seen in the form of overgeneralization. Overgeneralization in this context refers to an extension of a language rule to an exception to the rule. For example, in English it is common for an "s" to be added to the end of a word to indicate plurality. For example, we're talking about one dog versus two dogs. Young children generalize this rule to cases that are exceptions to the "add an s to the end of the word" rule by saying things like "those two geese" or "three mice". Apparently, the rules of the language are understood even when the exceptions to the rules are still being learned (Moskowitz, 1978).

LANGUAGE AND THINKING When we speak a language, we agree that words are representations of ideas, people, places and events. The particular language that children learn is linked to their culture and environment. But can words themselves affect the way we think about things? Psychologists have long questioned whether language shapes thoughts and actions, or whether our thoughts and beliefs shape our language. Two researchers, Edward Sapir and Benjamin Lee Whorf, began this investigation in the 1940s. They wanted to understand how the linguistic habits of a community encourage members of that community to interpret language in certain ways (Sapir, 1941/1964). Sapir and Whorf suggested that language determines thinking and suggested, for example, that a person whose ordinary language lacks present tense verbs would be challenged to think about the past (Whorf, 1956). Researchers have since identified this view as too absolute and have pointed to a lack of empiricism behind what Sapir and Whorf proposed (Abler, 2013; Boroditsky, 2011; van Troyer, 1994). Today, psychologists continue to study and discuss the relationship between language and thought.


Chapter 8 | thought and intelligence

WHAT DO YOU THINK? The importance of language Think about what you know about other languages; maybe you even speak multiple languages. Imagine for a moment that your closest friend is fluent in more than one language. Do you think your friend thinks differently depending on the language spoken? You may know some words that are not translatable into English from their original language. The Portuguese word saudade, for example, appeared in the 15th century, when Portuguese navigators left their homeland to explore the seas and travel to Africa or Asia. Those left behind described the emptiness and affection they felt as saudade (Figure 8.7). The word expresses many meanings, including loss, nostalgia, longing, warm memories and hope. There isn't a single word in English that encapsulates all these emotions in a single description. Do words like Saudade suggest that different languages ​​evoke different thought patterns in people? What do you think??

Figure 8.7 These two works show Saudade. (a) Saudade de Nápoles, which translates as "Missing Naples", was painted in 1895 by Bertha Worms. (b) Almeida Júnior painted Saudade in 1899.

Language can actually affect the way we think, an idea known as linguistic determinism. A recent demonstration of this phenomenon involves differences in the way English and Mandarin Chinese talk and think about time. English speakers tend to talk about time in terms that describe changes along a horizontal dimension, e.g. While Mandarin Chinese speakers also describe time in horizontal terms, it is not uncommon to also use terms associated with a vertical arrangement. . For example, the past can be described as "up" and the future as "down". It turns out that these language differences lead to differences in performance on cognitive tests designed to measure how quickly a person can identify temporal relationships. In particular, on a set of vertically prepared tasks, Mandarin Chinese speakers were faster at identifying temporal relationships between months. Indeed, Boroditsky (2001) sees these results as indicating that "habits in language encourage habits in thought" (p. 12). A group of researchers, wanting to study how language affects thinking, compared how English speakers and the Dani people of Papua New Guinea think and talk about colors. The Dani have two words for color: one word for light and one for dark. In contrast, the English language has 11

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coloring words. The researchers hypothesized that the number of color terms may limit how the Dani understand colors. However, the Dani were able to distinguish colors with the same ability as English speakers, despite having fewer words at their disposal (Berlin & Kay, 1969). A recent review of research aimed at determining how language can affect something like color perception suggests that language can affect perceptual phenomena, particularly in the left hemisphere. You may recall from previous chapters that for most people, the left hemisphere is associated with language. However, the right side (less linguistic hemisphere) of the brain is less affected by linguistic influences on perception (Regier & Kay, 2009)

8.3 Troubleshooting Learning Objectives By the end of this section, you will be able to: • Describe problem-solving strategies • Define algorithms and heuristics • Explain some common obstacles to effective problem solving People face problems every day – often many problems throughout the day. Sometimes these problems are simple: for example, to double a pizza dough recipe, you simply double each ingredient in the recipe. However, sometimes the issues we encounter are more complex. Suppose you have a deadline at work and you need to send a hard copy of a report to your manager by the end of the working day. The report is time sensitive and must be sent overnight. You finished the report last night, but your printer is not working today. What to do? First you need to identify the problem and then apply a strategy to solve it.

TROUBLESHOOTING STRATEGIES When you're faced with a problem—whether it's a complex math problem or a broken printer, how do you solve it? Before a solution to the problem can be found, the problem must first be clearly identified. After that, one of the many troubleshooting strategies can be applied, which will hopefully lead to a solution. A problem-solving strategy is a plan of action used to find a solution. Different action plans are associated with different strategies (Table 8.2). A well-known strategy is, for example, trial and error. The old adage "if it doesn't work the first time, try it, try it again" describes trial and error. Regarding your broken printer, you can try checking the ink levels and if that doesn't work, check that the paper tray is not clogged. Or maybe the printer isn't actually connected to your laptop. If you use trial and error, you will keep trying different solutions until you solve your problem. Although trial and error is not typically one of the most time-efficient strategies, it is commonly used. problem solving strategies




trial and error

Try other solutions until the issue is resolved.

Reboot the phone, turn off wifi, turn off bluetooth to determine why the phone is not working


Step by step problem solving formula

Instructions for installing the new software on your computer


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problem solving strategies





General problem solving framework

work backwards; Dividing a task into steps

Table 8.2

Another type of strategy is an algorithm. An algorithm is a problem-solving formula that provides step-by-step instructions for achieving a desired result (Kahneman, 2011). You can think of an algorithm as a recipe with very detailed instructions that produce the same result every time they are executed. Algorithms are often used in our everyday lives, especially in computer science. When you perform an Internet search, search engines like Google use algorithms to decide which entries appear first in their list of results. Facebook also uses algorithms to decide which posts to show in your newsfeed. Can you identify other situations where algorithms are used? A heuristic is another type of problem-solving strategy. While an algorithm must be followed exactly to produce a correct result, a heuristic is a general problem-solving framework (Tversky & Kahneman, 1974). You can think of them as mental shortcuts used to solve problems. A "rule of thumb" is an example of a heuristic. This rule saves the person time and energy when making a decision, but despite its time-saving properties, it is not always the best method for making a rational decision. Different types of heuristics are used in different situations, but the impetus to use a heuristic occurs when one of five conditions is met (Pratkanis, 1989): • When faced with too much information • When it is time to make a limited decision • When the decision to be made is not important • When too little information is available to make the decision • When an appropriate heuristic comes to mind at the same time

Working backwards is a useful heuristic where you start solving the problem by focusing on the end result. Consider this example: you live in Washington, D.C. and were invited to a wedding in Philadelphia at 4 pm on Saturday. Knowing that Interstate 95 normally reverses every day of the week, you need to plan your route and time your departure accordingly. If you need to be at the wedding service by 3:30 pm and it takes 2.5 hours with no traffic to get to Philadelphia, when should you leave the house? You use the reverse work heuristic to regularly plan your day's events, probably without thinking about it. Another useful heuristic is the practice of accomplishing a large goal or task by breaking it down into a series of smaller steps. Students often use this common method to complete a large research project or long school essay. For example, students typically brainstorm, develop a main thesis or topic, research their chosen topic, organize their information into an outline, write a draft, review and edit the draft, develop a final draft, organize the list of references, and revise their work before submitting the project. The big task becomes less overwhelming when it's broken down into a series of small steps.

DAILY CONNECTION Solving puzzles Problem solving skills can improve with practice. Many people challenge themselves with riddles every day.

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and other mental exercises to hone your problem-solving skills. Sudoku puzzles appear in most newspapers every day. Typically, a Sudoku puzzle is a 9×9 grid. The simple Sudoku puzzle below (Figure 8.8) is a 4×4 grid. To solve the puzzle, fill in the empty squares with a single digit: 1, 2, 3, or 4. Here are the rules: The numbers in each bold square, row, and column must add up to 10; However, each digit can appear only once in a bold box, row, and column. Measure yourself while solving this puzzle and compare your time with a classmate.

Figure 8.8 How long did it take you to solve this Sudoku? (You can see the answer at the end of this section.) Here's another popular type of puzzle (Figure 8-9) that challenges your spatial awareness. Without lifting the pencil from the paper, connect all nine dots with four straight connecting lines:



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Figure 8.9 Did you find out? (The answer is at the end of this section.) Once you understand how to solve this puzzle, you won't forget it. Consider the following logic puzzle scales (Figure 8.10). Sam Loyd, a well-known puzzle master, created and refined countless puzzles throughout his lifetime (Cyclopedia of Puzzles, undated).

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Figure 8.10 What steps did you take to solve this puzzle? You can read the solution at the end of this section.

Pitfalls in Problem Solving However, not all problems are successfully solved. What challenges prevent us from successfully solving a problem? Albert Einstein once said, "Insanity is doing the same thing over and over again and expecting a different result." Imagine a person in a room with four doors. A door that was always open in the past is now closed. The person who is used to leaving the room through that particular door keeps trying to leave through the same door even though the other three doors are open. The person is trapped - but they just need to go to another door instead of trying to get out through the locked door. A mindset is where you insist on solving a problem in a way that has worked in the past but is clearly not working now. Functional fixation is a type of mental set where you cannot perceive an object being used for anything other than what it was designed for. During the Apollo 13 mission to the moon, NASA engineers at Mission Control had to overcome functional fixation to save the lives of astronauts aboard the spacecraft. An explosion in one of the spacecraft's modules damaged several systems. Due to problems with the carbon dioxide filters, astronauts were at risk of poisoning due to increased levels of carbon dioxide. Engineers found a way for the astronauts to use spare plastic bags, duct tape and air hoses to create a makeshift air filter that saved the astronauts' lives.


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LINK TO LEARN Watch this scene from Apollo 13 ( where a group of NASA engineers are tasked with overcoming functional rigidity.

The researchers examined whether functional fixation is influenced by culture. In one experiment, people from the Shuar group in Ecuador were asked to use an object for a purpose other than that for which the object was originally intended. For example, participants heard a story about a bear and a rabbit separated by a river and were asked to choose from several items, including a spoon, cup, erasers, etc., to help the animals. The spoon was the only object long enough to encompass the imaginary stream, but when the spoon was presented in a way that reflected its normal use, participants took longer to select the spoon to solve the problem. (Deutsch & Barrett, 2005). The researchers wanted to know whether exposure to highly specialized tools, such as those experienced by people in industrialized countries, affects their ability to overcome their functional fixation. Functional fixation has been found in both industrialized and non-industrialized cultures (German & Barrett, 2005). To make good decisions, we use our knowledge and reasoning. Often this knowledge and reasoning is solid and sound. However, sometimes we are influenced by prejudice or other people manipulating a situation. Let's say you and three friends want to rent a house and have a combined budget of $1,600. Realtor only shows very run down houses for $1600 and then shows a very nice house for $2000. Could you ask each person to pay more rent to get the $2000 house? Why should the agent show you the dilapidated houses and the beautiful house? The broker may question your anchoring bias. Anchoring bias occurs when you focus on information when making a decision or solving a problem. If so, you're so focused on the amount of money you're willing to spend that you might not realize what types of homes are available at that price point. Confirmation bias is the tendency to focus on information that confirms your existing beliefs. For example, if you think your teacher isn't very nice, look at all the instances of rude behavior the teacher displays while ignoring the countless pleasant interactions he engages in on a daily basis. Hindsight bias makes you believe that the event you just experienced was predictable, when in fact it wasn't. In other words, you knew all along that things would turn out the way they did. Representative bias describes a faulty way of thinking in which you unintentionally stereotype someone or something; For example, you might assume that your teachers spend their free time reading books and engaging in intellectual conversations because the idea that they spend their time playing volleyball or going to an amusement park doesn't fit your stereotypes of teachers. Finally, the availability heuristic is a heuristic in which you make a decision based on recent examples, information or experiences that are readily available to you, even if it is not the best example for your decision. Prejudice tends to “conserve what is already established – to maintain our pre-existing knowledge, beliefs, attitudes and hypotheses” (Aronson, 1995; Kahneman, 2011). These distortions are summarized in Table 8.3. Decision bias summary




Tendency to focus on specific information when making decisions or solving problems


Focuses on information that confirms existing beliefs

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Decision bias summary




Believe that the event you just experienced was predictable


Unintentional stereotyping of someone or something


Decision is based on available precedent or potentially flawed example

Table 8.3

LINK TO LEARN Please visit this page ( to watch a clever video clip made by a high school teacher to explain these and other cognitive biases to his AP psychology students.

Can you determine how many marbles are needed to balance the scale in Figure 8.10? You need nine. Were you able to solve the tasks in Figure 8.8 and Figure 8.9? Here are the answers (Figure 8.11).

Figure 8.11


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8.4 What are intelligence and creativity? Learning Objectives By the end of this section, you will be able to: • Define intelligence • Explain the triarchical theory of intelligence • Recognize the difference between theories of intelligence • Explain emotional intelligence A four and a half year old boy is sitting at the kitchen table with his father reading him a new story. He turns the page to read more, but before he can start, the boy says, "Wait, Daddy!" He points to the words on the new page and reads aloud: "Come on, pig! Go!" The father stops and looks at his son. "Can you read this?" he asks. "Yes father!" And he points to the words and reads again: "Come on, pig! Go!" This father did not actively teach his son to read, although the child constantly asked questions about letters, words and symbols that he saw everywhere: in the car, in the store, on TV. The father wondered what else his son could understand and decided to try it out. He took a blank piece of paper and wrote a few simple words on a list: mom, dad, dog, bird, bed, truck, car, tree. He placed the list in front of the boy and asked him to read the words. "Mom, Dad, dog, bird, bed, truck, car, tree," he read, slowing down to carefully pronounce bird and truck. Then: "Did I do it, Daddy?" That's really good." The father gave his son a warm hug and continued reading the story of the pig, all the while wondering if his son's abilities were an indication of exceptional intelligence or just a normal pattern of language development. In this example, psychologists ask what constitutes intelligence and how it can be measured.

CLASSIFIING INTELLIGENCE What exactly is intelligence? The way researchers have defined the concept of intelligence has changed many times since the birth of psychology. British psychologist Charles Spearman believed that intelligence consists of a general factor called g that can be measured and compared between individuals. Spearman focused on the similarities between different intellectual abilities and what made each unique. However, long before the development of modern psychology, ancient philosophers such as Aristotle held a similar view (Cianciolo & Sternberg, 2004). Other psychologists believe that intelligence is not a single factor, but a collection of different abilities. In the 1940s, Raymond Cattell proposed a theory of intelligence that divided general intelligence into two components: crystallized intelligence and fluid intelligence (Cattell, 1963). Crystallized intelligence is characterized as acquired knowledge and the ability to retrieve it. When you learn, remember, and retrieve information, you use crystallized intelligence. You constantly use crystallized intelligence in your course, demonstrating that you master the information covered in the course. Fluid intelligence includes the ability to see complex relationships and solve problems. Navigating your way home after being redirected to an unfamiliar route due to roadworks would drain your fluency. Fluid intelligence helps you deal with complex and abstract challenges in your daily life, while crystallized intelligence helps you overcome concrete and simple problems (Cattell, 1963). Other theorists and psychologists believe that intelligence should be more practically defined. For example, what behaviors help you get ahead in life? What skills drive success? Think about it for a moment. Being able to recite all 44 Presidents of the United States in order is a great party trick, but does knowledge make you a better person? Robert Sternberg developed another theory of intelligence, which he called the triarchic theory of intelligence because he sees intelligence as having three parts (Sternberg, 1988): practical, creative,

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and analytical intelligence (Figure 8.12).

Figure 8.12 Sternberg's theory identifies three types of intelligence: practical, creative, and analytical.

Practical intelligence, as suggested by Sternberg, is sometimes compared to "street smarts". Being practical is finding solutions that work in your daily life, applying knowledge based on your experiences. This type of intelligence seems separate from the traditional understanding of IQ; Individuals with high scores on practical intelligence may or may not have comparable scores on creative and analytical intelligence (Sternberg, 1988). This story about the 2007 Virginia Tech shooting exemplifies both high and low practical intelligence. During the incident, a female student left the class to get a soda from a neighboring building. She intended to go back to class, but when she got back to the building after getting her lemonade, she saw that the door she had left earlier was locked with a chain from the inside. Instead of wondering why there was a chain hanging from the door handles, she went to the living room window and crawled back into the living room. In doing so, she may have exposed herself to the shooter. Luckily she wasn't shot. On the other hand, two students were walking across campus when they heard gunshots nearby. A friend said, "Let's have a look and see what's going on." The other student said, “No way, we have to run away from the gunfire.” They did just that. This allowed both of them to avoid damage. The student who crawled through the window showed some creative intelligence, but he didn't use common sense. She would have a low practical intelligence. The student who encouraged his friend to run away from the noise of the shots would have a much greater practical intelligence. Analytical intelligence is closely related to academic problem solving and computing. Sternberg says that analytical intelligence is demonstrated by the ability to analyze, evaluate, judge, compare and contrast. When reading a classic novel for a literature class, for example, it is often necessary to compare the motives of the book's main characters or analyze the historical context of the story. In a science course like anatomy, you need to study the processes by which the body uses different minerals in different human systems. When developing an understanding of this topic, use analytical intelligence. When solving a challenging mathematical problem, you would use analytical intelligence to analyze different aspects of the problem and solve it section by section. Creative intelligence is characterized by inventing or imagining a solution to a problem or situation. Creativity in this area can include finding a new solution to an unexpected problem or producing a beautiful work of art or a well-developed story. Imagine for a moment that you're camping in the woods with some friends and you realize you've forgotten your campsite coffee pot. The person in your group who successfully finds a way to make coffee for everyone is credited with greater creative intelligence. The theory of multiple intelligences was developed by Howard Gardner, a Harvard psychologist and former student of Erik Erikson. Gardner's theory, which has been refined for over 30 years, is a more recent development among intelligence theories. According to Gardner's theory, every human being has at least eight intelligences. Of these eight intelligences, a person typically excels in some and falls short in others.


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(Gardener, 1983). Table 8.4 describes each type of intelligence. multiple intelligences

tipo de inteligência


representative career

linguistic intelligence

Realizes different functions of speech, different sounds and meanings of words, can easily learn multiple languages

Journalist, writer, poet, teacher

Logical Mathematics Intelligence

Can recognize number patterns, strong ability to use reason and logic

scientist, mathematician

musical intelligence

Understands and appreciates rhythm, tone and tone; can play multiple instruments or act as a singer

composer, performer

Kinesthetic Physical Intelligence

High ability to control body movements and use the body to perform various physical tasks

Dancer, athlete, sports trainer, yoga teacher

spatial intelligence

Ability to perceive the relationship between objects and how they move in space

Choreographer, sculptor, architect, aviator, sailor

interpersonal intelligence

Ability to understand and be sensitive to the various emotional states of others

Counselor, social worker, salesman

intrapersonal intelligence

Ability to access personal feelings and motivations and use them to guide behavior and achieve personal goals

Key component of personal success over time

naturalistic intelligence

High ability to appreciate the natural world and interact with the species within it

Biologist, ecologist, environmentalist

Table 8.4

Gardner's theory is relatively new and needs more research to find empirical support. At the same time, his ideas challenge traditional notions of intelligence to include a broader range of abilities, although it has been suggested that Gardner simply renamed what other theorists call "cognitive styles" "intelligences" (Morgan, 1996). Furthermore, developing traditional measures of Gardner intelligence is extremely difficult (Furnham, 2009; Gardner & Moran, 2006; Klein, 1997). Gardner's interpersonal and intrapersonal intelligences are often grouped into a single type: emotional intelligence. Emotional intelligence includes the ability to understand one's own and others' emotions, show empathy, understand social relationships and cues, regulate one's emotions, and respond in culturally appropriate ways (Parker, Saklofske, & Stough, 2009). People with high emotional intelligence generally have well-developed social skills. Some researchers, including Daniel Goleman, author of Emotional Intelligence: Why It Can Matter More than IQ, argue that emotional intelligence is a better predictor of success than traditional intelligence (Goleman, 1995). However, emotional intelligence has been widely debated, with researchers pointing out inconsistencies in its definition and description and questioning the results of studies on a topic that is difficult to measure and study empirically (Locke, 2005; Mayer, Salovey, & Caruso, 2004).

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Intelligence can also have different meanings and values ​​in different cultures. If you live on a small island where most people make their living fishing from boats, knowing how to fish and how to repair a boat would be important. If you were an exceptional fisherman, your peers would probably think you were smart. If you were also adept at repairing boats, your intelligence could be known across the island. Think about your own family culture. What values ​​are important to Latino families? Italian families? In Irish families, hospitality and entertaining storytelling are hallmarks of the culture. If you're a skilled storyteller, chances are other members of Irish culture think you're smart. Some cultures place a high value on working together as a collective. In these cultures, the importance of the group replaces the importance of individual achievement. When you visit such a culture, your relationship to that culture's values ​​reflects your cultural intelligence, sometimes called cultural competence.

CREATIVITY Creativity is the ability to generate, create or discover new ideas, solutions and possibilities. Very creative people often have intense knowledge about something, work on it for years, look for new solutions, seek advice and help from other experts, and take risks. While creativity is often associated with art, it is actually a vital form of intelligence that drives people in many disciplines to discover something new. Creativity can be found in all areas of life, from the way you decorate your home to a new understanding of how a cell works. Creativity is often evaluated in terms of the ability to engage in divergent thinking. Divergent thinking can be described as thinking “outside the box”; allows an individual to come up with unique and multiple solutions to a given problem. In contrast, convergent thinking describes the ability to provide a correct or informed answer or solution to a problem (Cropley, 2006; Gilford, 1967).

DAILY CONNECTION Creativity Dr. Tom Steitz, Sterling Professor of Biochemistry and Biophysics at Yale University, has spent his career studying the structure and specifics of RNA molecules and how their interactions contribute to the production of antibiotics and defense against disease. As a result of his lifelong work, he was awarded the Nobel Prize in Chemistry in 2009. He wrote: "As I look back on the development and progression of my career in science, I am reminded of the vital importance of a good mentor in the early stages of career development and constant conversations, debates and face-to-face discussions with colleagues. at all stages of research. Remarkable discoveries, insights and developments do not happen in a vacuum" (Steitz, 2010, para. 39) From Steitz's comment, it is clear that a person's creativity, although an individual strength, benefits from interactions with others. Think of a time when your creativity was sparked by a conversation with a friend or colleague of yours. class How did this person influence you and what problem did you creatively solve?

8.5 Measures of Intelligence Objectives By the end of this section you will be able to: • explain how intelligence tests are developed • describe the history of the use of IQ tests • describe the purpose and usefulness of intelligence tests


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You're probably familiar with the term "IQ" and associate it with the idea of ​​intelligence, but what does IQ really mean? IQ stands for Intelligence Quotient and describes a score obtained on a test measuring intelligence. You've already learned that there are many ways in which psychologists describe intelligence (or rather intelligences). Likewise, IQ tests - the tools used to measure intelligence - have been the subject of debate throughout their development and use. When can an IQ test be used? What did we learn from the results and how can people use this information? IQ tests are expensive to administer and must be administered by a licensed psychologist. Intelligence tests have been seen as both a curse and a boon to educational and social policy. In this section, we'll look at what intelligence tests measure, how they are scored, and how they were developed.

MEASUREMENT OF INTELLIGENCE It seems that human understanding of intelligence is somewhat limited when we focus on traditional or academic intelligence. So how can intelligence be measured? And when we measure intelligence, how do we make sure we're measuring what we're really trying to measure (in other words, that IQ tests work as a valid measure of intelligence)? In the following sections we will examine how intelligence tests were developed and the history of their use. The IQ test has been synonymous with intelligence for over a century. At the end of the 19th century, Sir Francis Galton developed the first comprehensive intelligence test (Flanagan & Kaufman, 2004). Although he was not a psychologist, his contributions to intelligence testing concepts are still felt today (Gordon, 1995). Reliable intelligence tests (you may recall from earlier chapters that reliability refers to a test's ability to produce consistent results) began in earnest in the early 1900s with a researcher named Alfred Binet (Figure 8.13). Binet was asked by the French government to develop an intelligence test for children to identify which children might be struggling at school. it involved many verbal tasks. American researchers soon recognized the value of such tests. Louis Terman, a Stanford professor, modified Binet's work by standardizing how the test was administered and testing thousands of children of different ages to come up with an average score for each age. As a result, the test was normalized and standardized, meaning that the test was performed consistently on a sufficiently large representative sample of the population that the range of results resulted in a bell curve (bell curves are discussed later). Standardization means that the method of administration, evaluation and interpretation of the results is consistent. Normalization is about giving a large population a test so that data can be collected that compares groups, e.g. B. Age groups. The resulting data provides norms or reference ratings against which future ratings can be interpreted. Norms are not expectations of what a particular group should know, but a demonstration of what that group knows. The normalization and standardization of the test ensures that new results are reliable. This new version of the test was called the Stanford-Binet Intelligence Scale (Terman, 1916). Remarkably, an updated version of this test is still widely used today.

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Figure 8.13 French psychologist Alfred Binet helped develop intelligence tests. (b) This page is from a version of the 1908 Binet-Simon Intelligence Scale. The children tested were asked which face of each pair was prettier.

In 1939, in the United States, David Wechsler, a psychologist who spent part of his career working with World War I veterans, developed a new IQ test. Wechsler combined several subtests from other intelligence tests used between 1880 and World War I. These subtests explored a wide range of verbal and non-verbal skills, as Wechsler believed that intelligence "comprises a person's overall capacity to act intentionally, think rationally, and think about how to deal effectively with his or her environment" (Wechsler, 1958 , p. 7). He called the test the Wechsler-Bellevue Intelligence Scale (Wechsler, 1981). This combination of subtests has become one of the most widely used intelligence tests in the history of psychology. Although the name was later changed to the Wechsler Adult Intelligence Scale (WAIS) and revised several times, the objectives of the test have remained virtually unchanged since its inception (Boake, 2002). Today there are three intelligence tests credited to Wechsler, the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV), the Wechsler Intelligence Scale for Children (WISC-V), and the Wechsler Preschool and Primary Scale of Intelligence-IV (WPPSI - IV). ) (Wechsler, 2012). These tests are widely used in schools and communities across the United States and are regularly standardized and standardized as a means of recalibration. Interestingly, periodic recalibrations led to an interesting observation known as the Flynn effect. Named after James Flynn, who was one of the first to describe this trend, the Flynn effect refers to the observation that each generation has a significantly higher IQ than the one before it. However, Flynn himself argues that higher IQ scores do not necessarily mean that younger generations are smarter per se (Flynn, Shaughnessy, and Fulgham, 2012). As part of the recalibration process, the WISCV was distributed to thousands of children across the country, and children who take the test today are compared with their peers (Figure 8.13). The WISC-V consists of 14 subtests comprising five indices, which then reflect an IQ score. The five indices are Verbal Comprehension, Visual Spatial Comprehension, Fluency of Thought, Working Memory and Processing Speed. When the test is completed, subjects receive a score on each of the five indices and a total IQ score. The assessment methodology reflects the understanding that intelligence consists of multiple abilities across multiple cognitive domains and focuses on the mental processes the child used to arrive at their responses to each test item. Ultimately, the question remains of how valid intelligence tests are. Certainly the most modern versions of these tests reveal more than verbal skills, but specific skills that must be evaluated


Chapter 8 | thought and intelligence

For IQ tests, the degree to which each test can actually measure a person's intelligence and the use of IQ test results is still controversial (Gresham & Witt, 1997; Flynn, Shaughnessy, & Fulgham, 2012; Richardson, 2002 ; Schlinger, 2003). 🇧🇷

WHAT DO YOU THINK? Intellectually Disabled Criminals and the Death Penalty Atkins v. Virginia was a landmark before the United States Supreme Court. On August 16, 1996, two men, Daryl Atkins and William Jones, robbed, kidnapped and killed Eric Nesbitt, a local airman for the United States Air Force. A clinical psychologist examined Atkins and testified in the study that Atkins had an IQ of 59. The average IQ score is 100. The psychologist concluded that Atkins was mildly mentally retarded. The jury found Atkins guilty and he was sentenced to death. Atkins and his lawyers appealed to the Supreme Court. In June 2002, the Supreme Court reversed a previous ruling, ruling that executions of criminally retarded criminals were "cruel and unusual punishments" prohibited by the Eighth Amendment. The court wrote in its decision: Clinical definitions of intellectual disability require not only below-average intellectual ability but also significant limitations in adaptability. People with mental disabilities often know the difference between right and wrong and are capable of litigating. However, because of their impairments, they have, by definition, diminished abilities to understand and process information, communicate, abstract from error and learn from experience, think logically, control impulses, and understand the reactions of others. His deficiencies do not justify exemption from criminal penalties, but they mitigate his personal guilt (Atkins v. Virginia, 2002, para. 5). The court also ruled that there is consensus state law against executing the mentally disabled and that consensus should apply to all states. The Supreme Court decision left states free to define their own definitions of intellectual disability and intellectual disability. Definitions of who can be executed vary from state to state. In the Atkins case, a jury ruled that his IQ had increased as a result of frequent contacts with his lawyers and therefore received intellectual stimulation, and that he was now intelligent enough to be executed. He was given an execution date and then a stay of execution after it was revealed that co-defendant William Jones' attorneys were training Jones to "present testimony against Mr. Atkins consistent with the evidence" (Liptak, 2008 ). Following the revelation of this misconduct, Atkins was again sentenced to life in prison. Atkins v. Virginia (2002) highlights several issues related to society's beliefs about intelligence. In the Atkins case, the Supreme Court ruled that intellectual disability affects decision-making and therefore should affect the type of punishment these criminals receive. But where should the boundaries of intellectual disability be drawn? In May 2014, in a similar case (Hall v. Florida), the Supreme Court ruled that IQ scores cannot be used as the final determination of a prisoner's suitability for the death penalty (Roberts, 2014).

THE BELL CURVE Intelligence test scores follow the bell curve, a graph in the general shape of a bell. When the bell curve is used in psychological testing, the graph shows a normal distribution of a trait, in this case intelligence, in the human population. Many human characteristics naturally follow the bell curve. For example, if you sort all of your classmates by height, chances are a large group of them are the average American height: 5'4"-5'6". This grouping would fall in the middle of the bell curve and would represent the average height of American women (Figure 8.14). There would be fewer women closer to 4'11." The same goes for taller than average women: those closer to 5'11". The trick to finding a bell curve in nature is to use a large sample size. Without a large sample size, the bell curve is less likely to represent the larger population A representative sample is a subset of the population that accurately represents the general population For example, if you

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Chapter 8 | thought and intelligence


If you only measured the height of women in your classroom, you might not have a representative sample. Maybe the girls' basketball team wants to take this class together and everyone is in your class. Because basketball players tend to be taller than average, women in their class may not be a good representative sample of the American female population. However, if your sample includes all the women in your school, chances are their height will form a natural bell curve.

Figure 8.14 Are you below average, average or above average height?

The same principles apply to intelligence test scores. Individuals are assigned a score called the intelligence quotient (IQ). Different types of IQ tests have evolved over the years, but the way results are interpreted remains the same. The average IQ score on an IQ test is 100. Standard deviations describe how data are distributed in a population and provide context for large data sets. The bell curve uses standard deviation to show how all ratings differ from the average rating (Figure 8.15). On modern IQ tests, one standard deviation is 15 points. Therefore, a score of 85 would be described as "one standard deviation below the mean". How would you describe a score of 115 and a score of 70? Any IQ score that is within one standard deviation above or below the mean (between 85 and 115) is considered average, and 68% of the population have IQ scores in this range. An IQ score of 130 or higher is considered a higher level.


Chapter 8 | thought and intelligence

Figure 8.15 Most people have an IQ score between 85 and 115.

Only 2.2% of the population has an IQ below 70 (American Psychological Association [APA], 2013). A score of 70 or less indicates significant cognitive delays. When these are combined with significant deficits in adaptability, a person is diagnosed with an intellectual disability (American Association on Intellectual and Developmental Disabilities, 2013). Formerly known as intellectual disability, the accepted term is now intellectual disability and there are four subtypes: mild, moderate, severe and severe (Table 8.5). The Diagnostic and Statistical Manual of Psychological Disorders lists criteria for each subgroup (APA, 2013). Features of cognitive disorders

Intellectual disability subtype

Percentage of Population with Intellectual Disability



grades 3-6 proficiency level in reading, writing, and math; can work and live independently



basic reading and writing skills; functional self-care skills; requires some supervision



functional self-care skills; requires monitoring of environment and daily activities



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