Fundamentals of Human Neuropsychology, 8th Edition PDF

FUNDAMENTALS OF Human Neuropsychology EIGHTH EDITION BRYAN KOLB & IAN Q. WHISHAW University of Lethbridge Senior Vice President, Content Strategy: Charles Linsmeier Program Director, Social Sciences: Shani Fisher Executive Program Manager for Psychology: Daniel DeBonis Development Editor: Andrew Sylvester Assistant Editor: Anna Munroe Marketing Manager: Clay Bolton Marketing Assistant: Chelsea Simens Media Editor, Social Sciences: Stefani Wallace Director of Content Management Enhancement: Tracey Kuehn Senior Managing Editor: Lisa Kinne Senior Content Project Manager: Vivien Weiss Project Manager: Nagalakshmi Karunanithi, Lumina Datamatics, Inc. Lead Media Project Manager: Joe Tomasso Senior Workflow Project Manager: Lisa McDowell Production Supervisor: Robin Besofsky Executive Permissions Editor: Cecilia Varas Photo Researcher: Richard Fox, Lumina Datamatics, Inc. Director of Design, Content Management: Diana Blume Design Services Manager: Natasha Wolfe Interior Designer: Lumina Datamatics, Inc. Cover Design Manager: John Callahan Art Manager and New Illustrations: Matthew McAdams Composition: Lumina Datamatics, Inc. Cover Art: LILAWA.COM/Shutterstock Chapter Opener Background Art: oxygen/Getty Images Library of Congress Control Number: 202943827 ISBN: 978-1-319-36427-4 (epub) © 2021, 2015, 2009, 2003 by Worth Publishers All rights reserved. 1 2 3 4 5 6 25 24 23 22 21 20 Worth Publishers One New York Plaza Suite 4600 New York, NY 10004-1562 www.macmillanlearning.com To our first editor at W. H. Freeman & Company, W. Hayward (Buck) Rogers — who in 1979 stated “Nobody will publish this book, but I will” — and to Robert Thompson, who advised Buck that “the brain is the future and this book will define the field.” ABOUT THE AUTHORS Bryan Kolb received his Ph.D. from The Pennsylvania State University and conducted postdoctoral work at the University of Western Ontario and the Montreal Neurological Institute. In 1976, he moved to the University of Lethbridge, Alberta, where he is a professor of neuroscience. His current research examines how preconception and perinatal factors — including tactile stimulation, psychoactive drugs, stress, noise, and injury — modify the developing cerebral cortex and how these changes are related to behavior. Kolb is a fellow of the Royal Society of Canada; the Canadian Psychological Association (CPA); the Canadian Society for Brain, Behaviour, and Cognitive Science (CSBBCS); the American Psychological Association; and the Association of Psychological Science. Currently a fellow of the Child Brain Development program of the Canadian Institute for Advanced Research, he is a recipient of the Hebb Prize from the CPA and CSBBCS. He has received honorary doctorates from the University of British Columbia, Thompson Rivers University, Concordia University, and the University of Lethbridge. He is a recipient of the Ingrid Speaker Gold Medal for research, the distinguished teaching medal from the University of Lethbridge, and the Key to the City of Lethbridge. In 2017, he was appointed as an Officer of the Order of Canada. He and his wife train and show horses in Western riding performance events. Ian Q. Whishaw received his Ph.D. from Western University and is a professor of neuroscience at the University of Lethbridge. He has held visiting appointments at the University of Texas, the University of Michigan, the University of Cambridge, and the University of Strasbourg. He is a fellow of Clair Hall, Cambridge, the Canadian Psychological Association, the American Psychological Association, and the Royal Society of Canada. He is a recipient of the Canadian Humane Society Bronze Medal for bravery, the Ingrid Speaker Gold Medal for research, the distinguished teaching medal from the University of Lethbridge, and the Donald O. Hebb Prize. He has received the Key to the City of Lethbridge and has honorary doctorates from the University of British Columbia, Thompson Rivers University, and the University of Lethbridge. His research addresses the evolution and neural basis of skilled movement and the neural basis of brain disease. The Institute for Scientific Information includes him in its list of most-cited neuroscientists. His hobby is training and showing horses for Western performance events. BRIEF CONTENTS Preface Media and Supplements PART I Background CHAPTER 1 The Development of Neuropsychology CHAPTER 2 Research on the Origins of the Human Brain and Behavior CHAPTER 3 Nervous System Organization CHAPTER 4 The Structure and Electrical Activity of Neurons CHAPTER 5 Communication Between Neurons CHAPTER 6 The Influence of Drugs and Hormones on Behavior CHAPTER 7 Imaging the Brain’s Activity CHAPTER 8 Organization of the Sensory Systems CHAPTER 9 Organization of the Motor System PART II Cortical Functions and Networks CHAPTER 10 Principles of Neocortical Function CHAPTER 11 Cerebral Asymmetry CHAPTER 12 Individual Differences in Cerebral Organization CHAPTER 13 The Occipital Lobes and Networks CHAPTER 14 The Parietal Lobes and Networks CHAPTER 15 The Temporal Lobes and Networks CHAPTER 16 The Frontal Lobes and Networks CHAPTER 17 Cortical Networks and Disconnection Syndromes PART III Higher Functions CHAPTER 18 Learning and Memory CHAPTER 19 Language CHAPTER 20 Emotion and the Social Brain CHAPTER 21 Spatial Behavior CHAPTER 22 Attention and Consciousness PART IV Plasticity and Disorders CHAPTER 23 Brain Development and Plasticity CHAPTER 24 Neurodevelopmental Disorders CHAPTER 25 Plasticity, Recovery, and Rehabilitation of the Adult Brain CHAPTER 26 Neurological Disorders CHAPTER 27 Psychiatric and Related Disorders CHAPTER 28 Neuropsychological Assessment Glossary Name Index Subject Index CONTENTS Coverage links neuropsychological theory and assessment Preface Media and Supplements PART I Background CHAPTER 1 The Development of Neuropsychology PORTRAIT Living with Traumatic Brain Injury 1.1 The Brain Theory What Is the Brain? How Does the Brain Relate to the Rest of the Nervous System? 1.2 Perspectives on the Brain and Behavior Aristotle: Mentalism Descartes: Dualism Darwin: Materialism Contemporary Perspectives 1.3 Brain Function: Insights from Brain Injury Localization of Function Lateralization of Function Distributed Function Hierarchical Organization SNAPSHOT The Dilemma in Relating Behavior and Consciousness 1.4 The Neuron Theory Nervous System Cells Identifying the Neuron Relating Electrical Activity in Neurons to Behavior Connections Between Neurons As the Basis of Learning 1.5 Contributions to Neuropsychology from Allied Fields Neurosurgery Psychometrics and Statistical Evaluation Structural and Functional Brain Imaging CHAPTER 2 Research on the Origins of the Human Brain and Behavior PORTRAIT Evolving a Capacity for Language 2.1 Human Origins and the Origins of Larger Brains Research on Human Evolution Evolution of the Human Brain and Behavior Relating Brain Size and Behavior The Meaning of Human Brain-Size Comparisons The Acquisition of Culture 2.2 Comparative Research in Neuropsychology Understanding Brain Mechanisms Designing Animal Models of Disorders Describing Evolutionary Adaptations 2.3 Genes, Environment, and Behavior Mendelian Genetics and the Genetic Code SNAPSHOT A Genetic Diagnosis Applying Mendel’s Principles Genetic Engineering Phenotypic Plasticity and the Epigenetic Code CHAPTER 3 Nervous System Organization PORTRAIT Stroke 3.1 Neuroanatomy: Finding Your Way Around the Brain Describing Location in the Brain A Wonderland of Nomenclature 3.2 Overview of Nervous System Structure and Function Support and Protection Blood Supply Neurons and Glia Gray, White, and Reticular Matter Layers, Nuclei, Nerves, and Tracts 3.3 Origin and Development of the Central Nervous System 3.4 The Spinal Cord Spinal-Cord Structure and Spinal-Nerve Anatomy Spinal-Cord Function and the Spinal Nerves Cranial Nerve Connections Autonomic Nervous System Connections 3.5 The Brainstem The Hindbrain The Midbrain The Diencephalon 3.6 The Telencephalon The Basal Ganglia The Limbic System The Neocortex Fissures, Sulci, and Gyri Cortical Organization in Relation to Inputs, Outputs, and Function Cellular Organization in the Cortex Cortical Connections SNAPSHOT How Many Cortical Areas Are There? 3.7 The Crossed Brain CHAPTER 4 The Structure and Electrical Activity of Neurons PORTRAIT The Halle Berry Neuron 4.1 The Neuron’s Structure Overview of a Neuron The Neuron as a Factory The Cell Membrane: Barrier and Gatekeeper The Nucleus: Blueprints for Proteins Protein Synthesis: Transcription and Translation Applying Epigenetic Mechanisms Proteins: The Cell’s Products Golgi Bodies and the Cytoskeleton Crossing the Cell Membrane: Channels, Gates, and Pumps 4.2 The Neuron’s Electrical Activity Recording from an Axon How the Movement of Ions Creates Electrical Charges The Resting Potential Graded Potentials The Action Potential 4.3 Sending a Message Along an Axon The Nerve Impulse Saltatory Conduction and Myelin Sheaths SNAPSHOT Diagnosing MS 4.4 How Neurons Integrate Information Excitatory and Inhibitory Postsynaptic Potentials Voltage-Sensitive Channels and the Action Potential Summation of Inputs The Versatile Neuron 4.5 Stimulating and Recording with Optogenetics CHAPTER 5 Communication Between Neurons PORTRAIT Otto Loewi’s Dream Breakthrough 5.1 Neurotransmitter Discovery 5.2 The Structure of Synapses Chemical Synapses Electrical Synapses 5.3 Neurotransmission in Four Steps Step 1: Transmitter Synthesis and Storage Step 2: Neurotransmitter Release Step 3: Receptor-Site Activation Step 4: Neurotransmitter Deactivation 5.4 Types of Synapses Synaptic Variations Excitatory and Inhibitory Messages 5.5 Varieties of Neurotransmitters Four Criteria for Identifying Neurotransmitters Three Classes of Neurotransmitters 5.6 Excitatory and Inhibitory Receptors Ionotropic Receptors and Excitation Metabotropic Receptors and Inhibition Excitatory and Inhibitory Receptor Effects 5.7 Neurotransmitter Activating Systems and Behavior Neurotransmission in Peripheral Nervous System Divisions Activating Systems of the Central Nervous System SNAPSHOT Neurochemical Links Between SIDS and Sleep Apnea CHAPTER 6 The Influence of Drugs and Hormones on Behavior PORTRAIT The Case of the Frozen Addict 6.1 Principles of Psychopharmacology Routes of Drug Administration Routes of Drug Removal Revisiting the Blood–Brain Barrier Drug Routes and Dosage 6.2 Drug Actions in Synapses Steps in Synaptic Transmission Tolerance Sensitization Can Drugs Cause Brain Damage? 6.3 Grouping Psychoactive Drugs Group I: Antianxiety Agents and Sedative Hypnotics Group II: Antipsychotic Agents Group III: Antidepressants and Mood Stabilizers Group IV: Opioid Analgesics Group V: Psychotropics SNAPSHOT Cognitive Enhancement General Stimulants 6.4 Addiction Wanting-and-Liking Theory Treating Drug Abuse 6.5 Hormones Hierarchical Control of Hormones Classes and Functions of Hormones CHAPTER 7 Imaging the Brain’s Activity PORTRAIT Angelo Mosso 7.1 Recording the Brain’s Electrical Activity Single-Cell Recording Electroencephalographic Recording Event-Related Potentials Magnetoencephalography 7.2 Brain Stimulation Deep Brain Stimulation Transcranial Magnetic Stimulation 7.3 Static Imaging Techniques Imaging by X-Ray Computed Tomography 7.4 Dynamic Brain Imaging Positron Emission Tomography Magnetic Resonance Imaging Optical Tomography SNAPSHOT Tuning In to Language 7.5 Comparing Brain-Imaging Techniques and Uses Imaging Techniques, Pros and Cons Toward Multimodal Analyses CHAPTER 8 Organization of the Sensory Systems PORTRAIT Phantoms of the Brain 8.1 General Principles of Sensory-System Function Sensory Receptors Are Energy Filters Receptors Transduce Energy Receptive Fields Locate Sensory Events Receptors Identify Constancy and Change Receptors Distinguish Self from Other Receptor Density Determines Sensitivity Neural Relays Determine the Hierarchy of Motor Responses Central Organization of Sensory Systems 8.2 The Sensory Systems Vision Hearing Body Senses The Chemical Senses: Taste and Smell SNAPSHOT Watching the Brain Make Flavor 8.3 Perception Illusions Synesthesia Sensory Synergies CHAPTER 9 Organization of the Motor System PORTRAIT Mind in Motion 9.1 The Neocortex: Initiating Movement Mapping the Motor Cortex Using Electrical Stimulation Multiple Representations in the Motor Cortex The Movement Lexicon Premotor Cortex and Movement Plans Corticomotor-Neuron Activity in Planning and Executing Movements Mirroring Movement 9.2 Subcortical Motor Control The Basal Ganglia and Movement Force The Cerebellum and Motor Learning The Brainstem and Movement Control 9.3 Communicating with the Spinal Cord Spinal-Cord Pathways Spinal Motor Neurons SNAPSHOT Spinal-Cord Injury PART II Cortical Functions and Networks CHAPTER 10 Principles of Neocortical Function PORTRAIT Hemispherectomy 10.1 A Hierarchy of Function from Spinal Cord to Cortex The Spinal Cord: Reflexes The Hindbrain: Postural Support The Midbrain: Spontaneous Movement The Diencephalon: Affect and Motivation The Basal Ganglia: Self-Maintenance The Cortex: Intention 10.2 The Structure of the Cortex Cortical Cells SNAPSHOT Mapping the Human Cortex Cortical Layers, Efferents, and Afferents Cortical Columns, Spots, and Stripes Multiple Representations: Mapping Reality Cortical Systems: Frontal Lobe, Paralimbic Cortex, and Subcortical Loops Cortical Connections, Reentry, and the Binding Problem 10.3 Functional Organization of the Cortex A Hierarchical Model of Cortical Function Evaluating the Hierarchical Model A Contemporary Model of Cortical Function The Default Mode Network 10.4 Do Human Brains Possess Unique Properties? CHAPTER 11 Cerebral Asymmetry PORTRAIT Words and Music 11.1 Anatomical Asymmetries in the Human Brain Cerebral Asymmetry Neuronal Asymmetry Genetic Asymmetry 11.2 Asymmetries in Neurological Patients Brain Stimulation Patients with Lateralized Lesions Commissurotomy Patients Carotid Sodium Amobarbital Injection 11.3 Behavioral Asymmetries in the Intact Brain Asymmetry in the Visual System Asymmetry in the Auditory System Asymmetry in the Somatosensory System Asymmetry in the Motor System What Do Laterality Studies Tell Us about Brain Function? 11.4 Neuroimaging and Asymmetry 11.5 Theoretical Arguments: What Is Lateralized? Specialization Models Interaction Models SNAPSHOT Imaging the Brain’s Plasticity Preferred Cognitive Mode Measuring Behavior in Neuropsychology 11.6 Asymmetry in Nonhuman Animals Asymmetry in Birds Asymmetry in Nonhuman Primates CHAPTER 12 Individual Differences in Cerebral Organization PORTRAIT Individual Responses to Injury 12.1 Handedness and Functional Asymmetry Anatomical Studies Functional Cerebral Organization in Left-Handers Theories of Hand Preference SNAPSHOT Genetic Influences on Brain Structure 12.2 Sex Differences in Cerebral Organization Sex Differences in Children’s Behavior Sex Differences in Adult Behavior Sex Differences in Brain Structure Sex Differences Revealed in Functional Imaging Studies Gender Identity and Sexual Orientation Research with Neurological Patients Explanations for Sex Differences 12.3 Environmental Effects on Cerebral Organization Language and Culture Sensory and Environmental Deficits CHAPTER 13 The Occipital Lobes and Networks PORTRAIT An Injured Soldier’s Visual World 13.1 Occipital-Lobe Anatomy Subdivisions of the Occipital Cortex Connections of the Visual Cortex 13.2 A Theory of Occipital-Lobe Function Visual Networks Extending Beyond the Occipital Lobe Visual Pathways Beyond the Occipital Lobe Imaging Studies of Dorsal and Ventral Streams Top-Down Predictions in Vision 13.3 Disorders of Visual Pathways 13.4 Disorders of Cortical Function Case B.K.: V1 Damage and a Scotoma Case D.B.: V1 Damage and Blindsight Case G.Y. and Related Cases: V1 Damage and Conscious Vision Case B.I.: More than Blindsight Case J.I.: V4 Damage and Loss of Color Vision Case P.B.: Conscious Color Perception in a Blind Patient Case L.M.: V5 (MT) Damage and the Perception of Movement Case D.F.: Occipital Damage and Visual Agnosia Case V.K.: Parietal Damage and Visuomotor Guidance Cases D. and T.: Higher-Level Visual Processes Conclusions from the Case Studies 13.5 Visual Agnosia Object Agnosias Other Visual Agnosias 13.6 Visual Imagery SNAPSHOT Generating Mental Images CHAPTER 14 The Parietal Lobes and Networks PORTRAIT Varieties of Spatial Information 14.1 Parietal-Lobe Anatomy Functional Regions of the Parietal Cortex Connections of the Parietal Cortex Anatomy of the Dorsal Stream 14.2 A Theory of Parietal-Lobe Function Behavioral Uses of Spatial Information SNAPSHOT The Cognitive Neural Prosthetic The Complexity of Spatial Information 14.3 Somatosensory Symptoms of Parietal Lesions Somatosensory Thresholds Somatoperceptual Disorders Somatosensory Agnosias 14.4 Symptoms of Posterior Parietal Damage Bálint Syndrome Contralateral Neglect and Other Symptoms of Right Parietal Lesions The Gerstmann Syndrome and Other Left Parietal Symptoms Apraxia and the Parietal Lobe Drawing Spatial Attention Disorders of Spatial Cognition Left and Right Parietal Lobes Compared 14.5 Major Symptoms and Their Assessment Clinical Neuropsychological Assessment 14.6 Parietal-Lobe Networks CHAPTER 15 The Temporal Lobes and Networks PORTRAIT Living with Temporal-Lobe Damage 15.1 Temporal-Lobe Anatomy Subdivisions of the Temporal Cortex Connections of the Temporal Cortex Anatomy of the Ventral Stream 15.2 A Theory of Temporal-Lobe Function Sensory Processes Affective Responses Spatial Navigation The Superior Temporal Sulcus and Biological Motion Visual Processing in the Temporal Lobe Are Faces Special? Auditory Processing in the Temporal Lobe Olfactory Processing in the Temporal Lobe Asymmetry of Temporal-Lobe Function SNAPSHOT Why Do We Love Music? 15.3 Temporal-Lobe Networks 15.4 Symptoms of Temporal-Lobe Lesions Disorders of Auditory and Speech Perception Disorders of Music Perception Disorders of Visual Perception Disturbance of Visual- and Auditory-Input Selection Impaired Organization and Categorization Disorders of Odor Perception and Memory Inability to Use Contextual Information Memory Impairment Altered Affect and Personality Changes in Sexual Behavior 15.5 Clinical Neuropsychological Assessment of Temporal-Lobe Damage CHAPTER 16 The Frontal Lobes and Networks PORTRAIT Losing Frontal-Lobe Functions 16.1 Frontal-Lobe Anatomy Subdivisions of the Frontal Cortex Frontal-Lobe Networks 16.2 A Theory of Frontal-Lobe Function Functions of the Motor Cortex and Premotor Cortex Functions of the Prefrontal Cortex Heterogeneity of Frontal-Lobe Function SNAPSHOT Heterogeneity of Function in the Orbitofrontal Cortex 16.3 Executive Functions of the Frontal-Lobe Networks 16.4 Symptoms of Frontal-Lobe Lesions Disturbances of Motor Function Loss of Divergent Thinking Environmental Control of Behavior Poor Temporal Memory Impaired Social and Sexual Behavior Does a Spatial Deficit Exist? Clinical Neuropsychological Assessment of Frontal-Lobe Damage 16.5 Intelligence and the Frontal Lobes CHAPTER 17 Cortical Networks and Disconnection Syndromes PORTRAIT At Cross Purposes 17.1 Disconnecting Cognitive Functions 17.2 Anatomy of Cerebral Connections 17.3 Understanding Disconnection Toward a Modern Understanding of Disconnection 17.4 Hemispheric Disconnection Commissurotomy Callosal Agenesis and Early Transections 17.5 Disconnecting Sensorimotor Systems Olfaction Vision Somatosensory Functions Audition Movement Effects of Partial Disconnection SNAPSHOT An fMRI Study of Disconnection 17.6 Lesion Effects Reinterpreted As Disconnection Syndromes Apraxia Agnosia and Alexia Contralateral Neglect 17.7 Cortical Networks and Hubs The Development of Networks Hubs and Connectivity in Brain Dysfunction PART III Higher Functions CHAPTER 18 Learning and Memory PORTRAIT The Discovery of Memory Systems 18.1 Memory and Amnesia Varieties of Memory Varieties of Amnesia 18.2 Explicit Memory Episodic Memory Semantic Memory Neural Substrates of Explicit Memory Hemispheric Specialization for Explicit Memory 18.3 Implicit Memory Sparing of Implicit Memory in Amnesia Neural Substrates of Implicit Memory 18.4 Emotional Memory Evoking Negative Emotions Neural Substrates of Emotional Memory Unique Aspects of Emotional Memory 18.5 Short-Term Memory Short-Term Memory and the Temporal and Parietal Lobes Short-Term Memory and the Frontal Lobes Neuropsychological Testing for Short-Term Memory Function SNAPSHOT Disrupting Memory Formation 18.6 Special Memory Abilities Savant Syndrome Superior Autobiographical Memory 18.7 Issues in Relating Memory to Neural Structures Memory and Daily Life CHAPTER 19 Language PORTRAIT Multilingual Meltdown 19.1 What Is Language? Language Structure Producing Sound Core Language Skills 19.2 Searching for the Origins of Language Discontinuity Theories SNAPSHOT Genetic Basis for an Inherited Speech and Language Disorder Continuity Theories Experimental Approaches to Language Origins 19.3 Localization of Language Wernicke–Geschwind Model Anterior and Posterior Language Regions Dual Pathways for Language Speech Zones Mapped by Brain Stimulation and Surgical Lesions Speech Zones Mapped by Brain-Imaging Techniques Neural Networks for Language Nodes and Neural Webs for Language 19.4 Language Disorders Fluent Aphasias Nonfluent Aphasias Pure Aphasias 19.5 Localization of Lesions in Aphasia Cortical Language Components Subcortical Language Components Right-Hemisphere Contributions to Language 19.6 Neuropsychological Assessment of Aphasia Acquired Reading Disorders CHAPTER 20 Emotion and the Social Brain PORTRAIT Agenesis of the Frontal Lobe 20.1 The Nature of Emotion What Are Emotions? 20.2 Historical Views Investigating the Anatomy of Emotion The Emotional Brain Cortical Connections of Emotion 20.3 Candidate Structures in Emotional Behavior Processing Emotional Stimuli Brain Circuits for Emotion 20.4 Neuropsychological Theories of Emotion Asymmetry in Emotion Processing Temporal-Lobe Personality 20.5 Social Cognitive Theories of Emotion The Theory of Constructed Emotion SNAPSHOT Perception of Faces and Fear in the Case of S.M. Damasio’s Somatic Marker Hypothesis LeDoux’s Theory of Emotional Consciousness 20.6 The Social Brain and Social Cognition Frontal Lesions in Monkeys Cerebral Lesions in Humans Social Brain Networks The Self and Social Cognition CHAPTER 21 Spatial Behavior PORTRAIT Lost in Space 21.1 Spatial Behavior and Spatial Impairments Explaining Spatial Behavior Experimental Models of Spatial Behavior Neuropsychological Tests of Spatial Behavior Clinical Descriptions of Spatial Impairments 21.2 Dorsal- and Ventral-Stream Contributions to Spatial Behavior The Dorsal Stream in the Parietal Cortex The Dorsal Stream in the Frontal Cortex Location, Location, Location: The Ventral Stream and Frontal Cortex The Ventral and Dorsal Streams in Temporal Cortex SNAPSHOT Imaging the Hippocampi of London Taxi Drivers 21.3 The Brain’s Positioning System Place Cells Head-Direction Cells Grid Cells Location of Positioning System Cells 21.4 Individual Differences in Spatial Abilities 21.5 Scene Construction and Theory of Mind Scene Construction Theory Theory of Mind CHAPTER 22 Attention and Consciousness PORTRAIT A Curious Case of Neglect 22.1 Defining Attention and Consciousness 22.2 Attention Automatic and Conscious Processing Compared Neurophysiological Evidence of Attention Parallel Processing of Sensory Input Functional Imaging and Attention Networks of Attention Mechanisms of Attention 22.3 Inattention Absence of Visual Attention Sensory Neglect 22.4 Consciousness What Is Consciousness? The Neural Basis of Consciousness Cerebral Substrates of Consciousness Emotion and Consciousness SNAPSHOT Stimulating Nonconscious Emotion Nonconscious Processing PART IV Plasticity and Disorders CHAPTER 23 Brain Development and Plasticity PORTRAIT Plasticity and Language 23.1 Approaches to Studying Brain Development 23.2 Development of the Human Brain Neuron Generation Cell Migration and Differentiation Neural Maturation Synapse Formation and Pruning Glial Development Neural Development in the Adolescent Brain 23.3 Imaging Studies of Brain Development 23.4 Development of Problem-Solving Ability 23.5 Environmental Effects on Brain Development Developmental Effects of Aversive Environments Environmental Influences on Brain Organization Experience and Neural Connectivity Plasticity of Representational Zones in the Developing Brain 23.6 Brain Injury and Plasticity Effects of Age Effects of Brain Damage on Language SNAPSHOT Distinct Cortical Areas for Second Languages 23.7 Studying Plasticity after Early Brain Injury Effects of Early Brain Lesions on Behaviors Later in Life Effects of Early Brain Lesions on Brain Structure Later in Life Factors Influencing Plasticity after Early Cortical Injury CHAPTER 24 Neurodevelopmental Disorders PORTRAIT Life Without Reading 24.1 What Are Neurodevelopmental Disorders? Incidence of Neurodevelopmental Disorders 24.2 Causes of Intellectual Disability Cerebral Palsy Hydrocephalus Fragile-X Syndrome Fetal Alcohol Spectrum Disorder Down Syndrome 24.3 Communication Disorders Language Disorder Speech Sound Disorder Childhood-Onset Fluency Disorder Social Communication Disorder 24.4 Autism Spectrum Disorder Anatomical Correlates of ASD Causes of ASD 24.5 Attention-Deficit/Hyperactivity Disorder 24.6 Specific Neurodevelopmental Learning Disorders Reading Disabilities SNAPSHOT Imaging Sound Perception and Reading Disability Mathematical Disabilities Neuropsychological Evaluation Developmental Coordination Disorder 24.7 Developmental Influences on Neurodevelopmental Disorders Structural Damage and Toxic Effects Hormonal Effects Environmental Effects The Relative Age Effect 24.8 Adult Outcomes of Neurodevelopmental Disorders CHAPTER 25 Plasticity, Recovery, and Rehabilitation of the Adult Brain PORTRAIT Recovery from Stroke 25.1 Principles of Brain Plasticity Principle 1: Plasticity is common to all nervous systems, and the principles are conserved Principle 2: Plasticity can be analyzed at many levels Principle 3: The two general types of plasticity derive from experience Principle 4: Similar behavioral changes can correlate with different plastic changes Principle 5: Experience-dependent changes interact Principle 6: Plasticity is age dependent Principle 7: Plastic changes are time dependent Principle 8: Plasticity is related to an experience’s relevance to the animal Principle 9: Plasticity is related to the intensity or frequency of experiences Principle 10: Plasticity can be maladaptive 25.2 Can Plasticity Support Functional Recovery after Injury? Compensation Compared with Recovery What Happens When a Brain Is Injured? 25.3 Examples of Functional Restitution Recovery from Motor-Cortex Damage Recovery from Aphasia Recovery from Traumatic Lesions Recovery from Surgical Lesions Return to Daily Life 25.4 Research on Plasticity in the Injured Brain Functional Imaging after Cerebral Injury SNAPSHOT Using Imaging to Study Recovery Physiological Mapping after Cerebral Injury 25.5 Variables Affecting Recovery 25.6 Therapeutic Approaches to Recovery after Brain Damage Pharmacological Therapies Growth Factors Cell-Based Therapies Activity-Based Therapies Electrical Stimulation Cognitive Rehabilitation Tactile Stimulation Music and Other Behavioral Therapies CHAPTER 26 Neurological Disorders PORTRAIT Concussion 26.1 The Neurological Examination The Patient’s History The Physical Examination 26.2 Traumatic Brain Injury Open Head Injuries Closed Head Injuries Behavioral Assessment of Head Injury Recovering from and Preventing Head Injury 26.3 Epilepsy Classifying Seizures Treating Epilepsy 26.4 Tumors 26.5 Headache Types of Headache Treating Headache 26.6 Infections Types of CNS Infection Treating CNS Infection 26.7 Disorders of Motor Neurons and the Spinal Cord Myasthenia Gravis Poliomyelitis Multiple Sclerosis Paraplegia and Quadriplegia SNAPSHOT ALS: Amyotrophic Lateral Sclerosis Brown–Séquard Syndrome Hemiplegia 26.8 Motor Disorders Involving the Basal Ganglia Hyperkinetic Disorders Hypokinetic Disorders Causes of Parkinsonism Treating Parkinson Disease Psychological Aspects of Parkinson Disease 26.9 Cerebral Vascular Disorders Types of Cerebral Vascular Disease Treating Cerebral Vascular Disorders CHAPTER 27 Psychiatric and Related Disorders PORTRAIT Posttraumatic Stress Disorder 27.1 The Brain and Behavior 27.2 Schizophrenia Structural Abnormalities in Schizophrenic Brains Biochemical Abnormalities in the Brains of People with Schizophrenia Cognitive Symptoms in Schizophrenia Schizophrenia as a Neurodevelopmental Disorder 27.3 Mood Disorders Neurochemical Aspects of Major Depression Neuropathological and Blood-Flow Abnormalities in Major Depression Treatments for Major Depression Neurobiological Aspects of Bipolar Disorder 27.4 Anxiety Disorders 27.5 Psychosurgery 27.6 Psychiatric Symptoms of Cerebral Vascular Disease 27.7 Dementias Anatomical Correlates of Alzheimer Disease Putative Causes of Alzheimer Disease Clinical Symptoms and the Progression of Alzheimer Disease 27.8 Prion-Related Disorders 27.9 Sleep Disorders Narcolepsy Insomnia SNAPSHOT Restless Legs Syndrome 27.10 Micronutrients and Behavior CHAPTER 28 Neuropsychological Assessment PORTRAIT Lingering Effects of Brain Trauma 28.1 A Biopsychosocial Model for Neuropsychological Assessment 28.2 The Changing Face of Neuropsychological Assessment The Clinical Role of Neuropsychology 28.3 The Basics of Neuropsychological Assessment Goals of Neuropsychological Assessment Intelligence Testing in Neuropsychological Assessment Categories of Neuropsychological Assessment 28.4 Ten Core Features of Neuropsychological Assessment 28.5 The Problem of Effort 28.6 Developing Better Neuropsychological Procedures Leveraging Technology 28.7 Case Histories Case 1: Epilepsy Caused by Left-Hemisphere Tumor Case 2: Epilepsy Caused by Right-Hemisphere Infection Case 3: Rehabilitation SNAPSHOT Is Brain Injury Always Bad? Glossary Name Index Subject Index PREFACE Looking back to 1980, when the first edition of Fundamentals of Human Neuropsychology was produced, reminds us that as we were writing the book in the late 1970s, human neuropsychology did not yet exist as a unified body of knowledge about the human brain. The field had coalesced around hunches and inferences based on laboratory studies of monkeys, cats, and rats, as well as on scattered studies of humans with assorted brain injuries. Over the past 40 years, as neuropsychology has expanded, cognitive neuroscience, social neuroscience, and computational neuroscience have emerged as new disciplines. Our understanding of brain anatomy and function have vastly improved through advances in the ever-more-incisive use of noninvasive neuroimaging and other technical innovations and the generation of an abundant body of research. Studies of nonhuman species remain central to human neuropsychology’s core principles — especially in understanding the structure and connectivity of the primate brain — but these studies focus more on mechanisms than on behavioral phenomena. Many researchers today share a bias that functional neuroimaging can replace the study of brain-injured humans and laboratory animals. To others, this outcome seems unlikely, given the complexity of brain processes as well as limitations on examining brain organization and function at a molecular level. Human and nonhuman studies are complementary, and this eighth edition reflects their continuing intellectual evolution as the knowledge base rapidly grows: Neuroimaging has led the renaissance in understanding neural networks and appreciating the brain’s connectome. The intersection of the study of the discrete brain regions and investigations into neural networks, driven by advances in brain imaging and statistical analysis, continues to shape our understanding of brain development and behavior interpreted through both theoretical and clinical work. As in previous editions, coverage of recent research into these dynamic neural networks appears throughout the eighth edition, especially in Parts II and III. Major sections on neural networks have been added to each of the chapters detailing cortical anatomy (Chapters 13–17) and in the discussions of higher functions (e.g., Chapter 19 now includes a description of the neuroimaging techniques that reveal the Brain Dictionary). Epigenetics explains how our behaviors change our brains. We introduce basic genetics and epigenetic principles in Section 2.3 and highlight both factors throughout the book to reflect the expanding emphasis on epigenetics as a factor in cerebral organization. Neuropsychological assessment is vital for evaluating patients with focal brain injuries. One unexpected consequence of the cognitive neuroscience revolution is a declining appreciation for neuropsychological theory and clinical focus. The maze icon found in every chapter identifies for the reader particular discussions, cases, tables, and figures that link theory and assessment throughout the book. Content and Structure Fundamentals of Human Neuropsychology differs from other textbooks of psychology, cognitive neuroscience, or neuroscience. In our experience, students find it helpful to see the brain from two organizational perspectives: anatomical and behavioral. Note that we have revised the part structure for the eighth edition — grouping together the middle chapters, which fell under separate part headings in previous editions — to better reflect our understanding of localization and neural networks. This change does not impact the chapter-by-chapter organization. Part I: Chapters 1–7 provide the requisite basic background — about history, evolution, genetics and epigenetics, anatomy, physiology, pharmacology, and methodology. In this edition, we conclude this part with two chapters describing the organization of the sensory and motor systems. Part II: Equally fundamental to understanding subsequent material, Part II begins, in Chapters 10–12, with an outline of the functions of the cerebral cortex and then digs into the anatomically defined cortical regions in Chapters 13–17. Understanding the organization of the cerebral cortex is central to appreciating how the brain functions to produce the complex processes that underlie complex behaviors. Part III: The psychological constructs presented in Chapters 18–22 — such as language, memory, social behavior and affect, spatial behavior, and attention and consciousness — emerge from the neuronal networks explored in Part II. Shifting from anatomy to psychological processes naturally means revisiting material from earlier parts — but this time in the context of psychological theory rather than anatomy. Part IV: Chapters 23–28 consider brain development and plasticity and include more detailed discussions of brain disorders introduced earlier in the book. Chapters on neurological and psychiatric disorders and on neuropsychological assessment continue the book’s emphasis on approaching human brain functions from an interdisciplinary perspective. Highlights of the Eighth Edition As with every new edition, we have sought to balance our presentation of the fundamental principles of neuropsychology with recent developments in research and clinical application, particularly related to the contributions of neuroimaging studies and network analysis. Maintaining a manageable length has meant sacrificing some detail that may have been prominent in previous editions, sometimes reaching back to the first edition. However, we hope you agree that the eighth edition will give students a grounding in the important concepts and innovations in this rapidly changing and fertile field. Here, we present some of the key changes, although this list by no means captures the full extent of the revisions and new research that has been added to this edition. Part I Background The discussion of genetics in Section 2.3 has been updated to reflect current estimates of gene mutation accumulation across the human life span and to incorporate recent developments in gene modification and CRISPR methods. A discussion of recent research on the heritability of epigenetic changes has also been added. Updates throughout Section 3.6 reflect current research on cortical connectivity, including a new Snapshot detailing Glasser and colleagues’ work in FACT analysis and their development of the Multimodal Map. An expanded discussion of the versatile neuron in Section 4.4 includes a new figure detailing some of the ways an action potential travels across a neuron. The discussion of neurotransmitter-activating systems in Section 5.7 includes a new figure illustrating the complex interactions between neurons and their targets. Section 6.4 on addiction has been heavily revised based on new research and includes expanded discussions of wanting-and-liking theory and treatment. The discussion of neural networks and mapping has been expanded in Chapter 7, particularly in the comparison of imaging techniques in Section 7.5. The discussion of mirror neurons in Section 9.1 has been updated to include recent challenges. Section 9.2 has been reorganized and now includes recent research on the role of the basal ganglia in emotional expression. A new Snapshot in Section 9.3 discusses spinal-cord injury and treatment, including recent innovations in nanotechnology. Part II Cortical Functions and Networks Discussions of brain mapping have been updated throughout Chapter 10, particularly in the discussion of the Human Connectome Project and the new coverage of the default mode network in Section 10.3. Section 10.4 has also undergone significant revision and incorporates a discussion of FACT analysis and developments in cortical mapping. New research on asymmetry has been integrated throughout Chapters 11 and 12, especially in relationship to brain-mapping analysis. Recent genetic theories of handedness are presented in Section 12.1. The discussion of sex differences in Section 12.2 incorporates recent research on brain imaging and gender identity and sexual orientation. Section 12.3 includes a new discussion of brain organization in blind people and significant updates to the discussion of the environmental and SES effects. The discussion of asymmetry in nonhuman animals has been updated and moved from Section 12.4 to Section 11.6. The discussions of occipital-lobe anatomy and function in Sections 13.1 and 13.2 have been updated with recent fMRI and rsfMRI research on brain topography and network analysis, including coverage of the proposed triple streams for visual processing. A new case study has been added to Section 13.4. The discussions in Section 14.1 of the precuneus regions and cytoarchitecture of the parietal cortex have been expanded with new research. A new Snapshot on the cognitive neural prosthetic has been added to Section 14.2. A new Section 14.6 on parietal-lobe networks covers recent research on IPL and TPJ anatomy and the parietal memory network. The discussion of temporal-lobe anatomy and function in Sections 15.1 and 15.2 now covers olfactory projections and processing, and a discussion of disorders of odor perception has been added to Section 15.3. A brief discussion of language processing and a new Snapshot on emotional responses to music have been added to Section 15.2. A major section 15.3 on temporal-lobe networks has been added as well. Section 16.1 now includes a brief section and new figure that describe the medial frontal cortex, and the discussion of the anterior cingulate cortex has been expanded. A major Section 16.3 has been added, covering executive functions of the frontal-lobe networks. The discussion of intelligence in Section 16.5 has been expanded and updated with coverage of the P-FIT model. The discussion of cortical networks and hubs in Section 17.7 has been updated and now includes discussions of the “rich-club” phenomenon and of modularity and functional integration. Part III Higher Functions Section 18.1 has been significantly restructured to provide an introductory discussion of memory and amnesia, including a new discussion of TBI and amnesia, before tackling specific forms of memory in later sections. The discussion of neurotransmitter-activating systems has moved to Section 18.3. Section 18.7 has been added to discuss leading theories of the neural substrates related to memory. The discussion of anatomical areas associated with language in Section 19.3 has been reorganized and updated with findings from recent MRI and fMRI studies, including a new discussion on the semantic network and the Brain Dictionary (with a new figure from the WordNet software). Section 19.5 has also been updated with recent findings from studies of stroke patients. Section 20.4 has been restructured and now includes a revamped discussion of asymmetry in emotion processing. A new Section 20.5 updates the discussion of social cognitive theories of emotion and includes new considerations of the multicomponent emotion process model and the theory of constructed emotion, as well as a new Snapshot on amygdala damage and fear processing. Section 20.6 covers recent fMRI research on the social brain network. Section 21.1 has been reorganized to introduce the reader to a variety of spatial behaviors ahead of the discussion of impairments. Section 21.2 includes a new section on projections of the ventral stream to the frontal cortex. A new Section 21.3 consolidates coverage of the brain’s positioning system. The discussions of individual differences in Section 21.4 and scene construction in Section 21.5 have been thoroughly revised and reorganized. The discussion of attention networks in Section 22.2 includes one new table outlining associated neuromodulators and another outlining associated disorders, and this section also covers a recently developed theory on mechanisms of attention. The discussion on consciousness in Section 22.4 has been reorganized and includes new treatments of integrated information theory and of the role of the frontoparietal circuit in consciousness. Part IV Plasticity and Disorders Recent studies comparing neurogenesis in human and nonhuman animals has been added to Section 23.2, and significant updates have been made to the discussion of adolescence and brain plasticity. Section 23.3 on imaging studies includes coverage of the recently developed MRI technique known as neurite orientation dispersion and density imaging. Coverage of environmental effects in Section 23.5 has been thoroughly updated, particularly in the discussions of ACEs, prenatal effects and treatments, and the microbiome, and now includes discussions of the impacts of lead poisoning and of SES. Chapter 24 has been significantly updated and restructured; it now opens with a revamped Section 24.1 describing neurodevelopmental disorders and then proceeds to separate sections that cover causes of intellectual disabilities, communication disorders, autism spectrum disorder, attention-deficit/hyperactivity disorder, specific neurodevelopmental learning disorder (including a new Snapshot on imaging sound perception and reading disability), developmental influences, and adult outcomes. The Chapter 25 Portrait now covers stroke. Updates throughout the discussion of therapeutic approaches to recovery in Section 25.6 include new coverage of growth factors and of rTMS and DBS, as well as new research on cognitive rehabilitation. The Chapter 26 Portrait now covers concussion, and the discussion of TBI in Section 26.2 has been updated. Section 26.3 has been revised with new coverage of dissociative seizures and expanded coverage of treatment. A new Snapshot discusses ALS, and a new Section 26.8 incorporates material previously in Chapter 27 on motor disorders involving the basal ganglia. The Chapter 27 Portrait now covers posttraumatic stress disorder. The discussion of schizophrenia in Section 27.2 includes recent research on white-matter pathology, associated genetic markers, and cognitive symptoms. Section 27.3 now includes a discussion of treatments for major depression. Section 27.7 on dementias includes a new section on brain age. A new Section 27.8 describes prion-related disorders, and a new Section 27.9 incorporates material on sleep disorders (including the Snapshot) that previously appeared in Chapter 26. Chapter 28 has undergone significant changes, including a new opening Section 28.1 on the biopsychosocial model for neuropsychological assessment, a reorganized Section 28.2 on changes in assessment (with a new discussion of clinical neuropsychology), a new Section 28.4 on core features of neuropsychological assessment, and a new Section 28.6 on ways to improve neuropsychological procedures, including a discussion of technology. A new case study and Snapshot have been added to Section 28.7. Updates to the glossary corresponding to new chapter content reflect the changing face of neuropsychology and include some unexpected topics — such as FACT analysis in Section 3.6 and neuroeconomics in Section 22.4. In addition to new figures that supplement the updated content, we have also removed some of the seventh edition images that came directly from published papers, in many cases replacing them with new illustrations produced by Macmillan’s artists. This change has allowed us to tailor many of these images to the discussion at hand. Finally, the end-of-chapter summaries have been revised with headings that situate each section within the framework of neuropsychology principles. Acknowledgments As in the past, we must sincerely thank many people who have contributed to the development of this edition. We are particularly indebted to colleagues from around the world who have been so supportive and have strongly encouraged us to include their favorite topics. We have done so wherever possible. We also thank the reviewers solicited by our editors on the seventh edition of Fundamentals of Human Neuropsychology, as well as those who reviewed prior editions. Their anonymous comments contributed varied perspectives and valuable points of consensus that helped us shape the new edition. Julie Alvarez, Tulane University Benjamin Balas, North Dakota State University Marlene Behrmann, Carnegie Mellon University Edward Castañeda, The University of Texas at El Paso Kelly Cate, University of North Georgia–Dahlonega Tracy Centanni, Texas Christian University Benjamin Clark, University of New Mexico–Albuquerque Derin Cobia, Brigham Young University Howard Cromwell, Bowling Green State University Pauline Dibbets, Maastricht University Peter Donovick, The State University of New York at Binghamton Mauricio Garcia-Barrera, University of Victoria Kim Good, Dalhousie University Amanda Higley, Point Loma Nazarene University Katherine Hughes, Florida Atlantic University–Jupiter Almut Hupbach, Lehigh University Eliyas Jeffay, University of Toronto–Mississauga Jamie Lillie, Argosy University, Schaumburg Diana Lim, Concordia University, Montreal Kenneth Long, California Lutheran University Bernice Marcopulos, James Madison University Salvatore Massa, Marist College Taryn Myers, Virginia Wesleyan College Martin Paczynski, George Mason University Rosie Reid, Dublin Business School Tony Robertson, Vancouver Island University Keith Shafritz, Hofstra University Patti Simone, Santa Clara University Joe Wayand, Walsh University Robin Wellington, St. John’s University Susan Zup, University of Massachusetts–Boston The staff at Macmillan Learning are amazing and have made this task far more enjoyable than it would have been without them. These folks include our executive program manager Daniel DeBonis and assistant editor Anna Monroe; our senior content project manager Vivien Weiss and senior workflow project manager Lisa McDowell; and the production and composition team at Lumina Datamatics, led by Nagalakshmi Karunanithi, for their talents in translating the manuscript onto the page. Our thanks to director of design Diana Blume and design services manager Natasha Wolfe for maintaining an inviting, accessible new book design as we shifted to a larger trim size, as well as to John Callahan for a striking cover. And copyeditor Kitty Wilson has contributed to the book’s clarity, consistency, and accuracy. Once again, Cecilia Varas coordinated photo research, ably assisted by researcher Richard Fox. They doggedly pursued sources and found photographs and other illustrative materials that we would not have found on our own. We remain indebted to art manager Matt McAdams for his excellent work in maintaining the illustration program and converting a variety of brain scans and other original artwork into anatomical illustrations. And a special thanks to our development editor, Andrew Sylvester, who had big shoes to fill in replacing our only previous development editor, Barbara Brooks, to whom we remain extremely grateful for her past work. Seeing the book for the first time, Andrew has brought a freshness that shows throughout. Due to the extensive revisions of the art program as noted above, Andrew has played a key role in not only replacing but improving on the artwork, which was not an easy task. Furthermore, having to work at home with small children during the COVID-19 pandemic made his job all the more difficult, but he clearly rose to the occasion. Once again, errors remain solely attributable to us. In a field that has expanded so dramatically since our first edition, we hope that readers continue to acquire a breadth of knowledge in the ever-expanding world of human neuropsychology. Finally, we thank our students, who have motivated us to continue the journey of Fundamentals of Human Neuropsychology for over 40 years. When we began writing the book in 1977, we could never have imagined that we would still be writing it in 2020! Seeing the faces of students light up when they begin to understand how the marvelous brain can produce cognition and behavior continues to be rewarding and is what this endeavor is all about. Once again, we must thank our wives for putting up with us when we were distracted by deadlines and may not always have been our “usual” selves. Bryan Kolb and Ian Q. Whishaw MEDIA AND SUPPLEMENTS Fundamentals of Human Neuropsychology, Eighth Edition, features a variety of supplemental materials for students and teachers of the text. For more information about any of the items below, please visit Macmillan’s online catalog at http://www.macmillanlearning.com. A comprehensive Web resource for teaching and learning LaunchPad combines Macmillan Learning’s award-winning media with an innovative platform for easy navigation. For students, it is the ultimate online study guide, with an interactive e-book and quizzing. For instructors, LaunchPad is a full course space where class documents can be posted, quizzes are easily assigned and graded, and students’ progress can be assessed and recorded. Whether you are looking for the most effective study tools or a robust platform for an online course, LaunchPad is a powerful way to enhance your class. LaunchPad can be previewed and purchased at launchpadworks.com. Fundamentals of Human Neuropsychology, Eighth Edition, & LaunchPad (six-month access) can be ordered with ISBN-10: 978-1-319-41413-9. LaunchPad for Fundamentals of Human Neuropsychology, Eighth Edition, includes the following resources: NEW! NEUROSCIENCE IN ACTION, VOLUME I This new collection of online activities offers students the ability to understand neuronal processes in action. The 15 new activities vividly illustrate the foundational processes that the reader can only imagine by reading. Students come away more fully understanding topics such as the conduction of the action potential, the integration of neural inputs, and the action of neurotransmitters. A perfect accompaniment to an online or hybrid course, each activity is fully assessable with multiple-choice questions. This collection is indispensable for bringing fundamental neuroscience concepts to life. Neuroscience in Action, Volume I 1. Evolution of Brains and Behavior 2. Finding Your Way Around the Brain 3. Anatomy of the Brain 4. Build a Neuron 5. Understanding Potential 6. Sending Signals 7. Bridging the Divide 8. Getting to Know Your Neurotransmitters 9. Visual Pathways: The What and the How 10. Receptive Fields and Visual Perception 11. Auditory System: How the Ears Process Sound 12. Motor Control: Getting Things Moving 13. Somatosensory System: How We Feel 14. Hypothalamic Circuit: Feedback and Regulation 15. Reward System: Wanting and Liking CHAPTER QUIZZES are a great way for students to test their knowledge. Each multiple-choice quiz covers topics from across the chapter. Valuable to both student and instructor, the practice quizzes are fully editable and make assessment quick and easy to set up. AN INTERACTIVE E-BOOK allows students to highlight, bookmark, and make notes, just as they would with a printed textbook. The search function and in-text glossary definitions make the text ready for the digital age. VIDEO ACTIVITIES cover a variety of topics to illustrate and inform concepts from the text. Expanded! Test Bank The Test Bank includes a battery of more than 1000 multiple-choice and short-answer test questions authored by Robin Wellington (St. John’s University) and Mallory L. Malkin, PhD (Licensed Clinical Psychologist). Each item is keyed to the page in the textbook on which the answer can be found. All the questions have been thoroughly reviewed and edited for accuracy and clarity. The Test Bank is available through the Macmillan Learning website, at www.macmillanlearning.com. Illustration Slides and Lecture Slides Available for download from launchpadworks.com, these slides can either be used as they are or customized to fit the needs of your course. There are two sets of slides for each chapter. The illustration slides feature all the figures, photos, and tables. The lecture slides feature main points of the chapter with selected figures and illustrations. CHAPTER 1 The Development of Neuropsychology PORTRAIT Living with Traumatic Brain Injury L.D., an aspiring golfer, had worked as a cook. Following an accident in which he was injured, the lawyers negotiating his case debated how L.D. continued to excel at golf but at the same time was unable to return to his former work as a cook. Four years earlier, when he was 21, L.D. had been invited to participate in a sports promotion at a pub. He became ill and was helped onto a balcony by a pub employee. On the balcony, he slipped out of the employee’s grasp and fell down five flights of stairs, striking his head against the stairs and wall. He was taken, unconscious, to the emergency ward of the local hospital, where his concussion was assessed on the Glasgow Coma Scale rating as 3, the lowest score on a scale from 3 to 15. A computed tomography (CT) scan revealed bleeding and swelling on the right side of L.D.’s brain. A neurosurgeon performed a craniotomy (skull removal) over his right frontal cortex to relieve pressure and remove blood. A subsequent CT scan revealed further bleeding on the left side of his brain, and a second craniotomy was performed. When discharged from the hospital 6 weeks later, L.D.’s recall of the events consisted only of remembering that he had entered the pub and then becoming aware that he was in a hospital 3 weeks later. L.D., unable to return to work as a cook, was seeking compensation from the company that had hosted the sports promotion and from the pub where he had been injured. We found that L.D. became frustrated and annoyed when attempting to cook. He had lost his sense of smell and taste. In addition, he was not interested in socializing, and he and his girlfriend had ended their 4-year relationship. We administered a comprehensive neuropsychological examination, and his scores on most tests were average, except for tests of verbal memory and attention, which were very low. Magnetic resonance imaging (MRI), a brain-scanning method that can reveal the brain’s structure in detail, showed some diffuse damage to both sides of his brain. The accompanying positron emission tomography (PET) images contrast blood flow in a healthy brain (top) and blood flow in patients like L.D. (bottom). Based on previous patients with traumatic brain injuries and behavioral and brain symptoms similar to L.D.’s, we recommended compensation, which L.D. did receive, in addition to assistance in finding work less demanding than cooking. He was able to live on his own and successfully returned to playing golf. According to National Institute of Neurological Disorders and Stroke estimates, 1.7 million U.S. residents receive medical attention each year after suffering traumatic brain injury (TBI), a wound to the brain that results from a blow to the head (detailed in Section 26.3, including concussion, the common term for mild TBI). TBI is a contributing factor in 30% of deaths due to accidents and can result from head blows while playing sports, from falls, and from vehicle accidents. While also the most common cause of discharge from military service (Lippa et al., 2019), TBI most frequently occurs in children under age 6, young adults, and those over age 65. In addition to these known cases, an unknown number of people endure TBI each year but do not report injury. L.D. is not unusual in that, in his own view and in the view of acquaintances, he has mainly recovered but is unable to return to his former level of employment. L.D. is also not unusual in that he puzzles both friends and experts with his ability to do one thing well yet is unable to do another. Finally, L.D. is not unusual in that the diffuse brain injury revealed by brain- scanning methods (see Chapter 7) does not predict his abilities and disabilities well. Neuropsychological testing is required to confirm that L.D. has enduring cognitive deficits and to identify those deficits. L.D.’s poor scores on tests of memory and attention are associated with his difficulty in everyday problem solving, a mental skill referred to as executive function. Thus, L.D. can play golf at a high level because it requires that he execute only one act at a time, but he cannot prepare a meal, which requires him to multitask. As we will describe later in this chapter, the ability to play golf and the inability to cook can be interpreted in a variety of ways, and coming to a satisfactory conclusion requires neuropsychological detective work. This book’s objective is to describe neuropsychology, the scientific study of the relationships between brain function and behavior. Neuropsychology draws information from many disciplines — anatomy, biology, biophysics, ethology, pharmacology, physiology, physiological psychology, and philosophy among them. Neuropsychological investigations into the brain– behavior relationship can identify impairments in behavior that result from brain trauma and from diseases that affect the brain. Neuropsychology can also provide insight into the central question “How does the brain work?” Neuropsychology is strongly influenced by two theories of brain function: the brain theory, which states that the brain is the source of behavior; and the neuron theory, the idea that the unit of brain structure and function is the neuron, or nerve cell. This chapter traces the development of these two theories and describes how they shape the insights that guide present-day investigations of the brain. 1.1 The Brain Theory People knew what the brain looked like long before they had any idea of what it did. Early in human history, hunters must have noticed that all animals have brains and that the brains of different animals, including humans, vary greatly in size but look quite similar. Over the past 2000 years, anatomists have produced drawings and images of the brain, named its distinctive parts, and developed methods to describe the functions of those parts. What Is the Brain? Brain is an Old English word for the tissue found within the skull (cranium). Figure 1.1A shows a human brain as oriented in the skull of an upright human. Just as your body is symmetrical, having two arms and two legs, so is your brain. Its two almost symmetrical halves are called hemispheres (half spheres), one on the left side of the body and the other on the right, as shown in the frontal view. If you make your right hand into a fist and hold it up with the thumb pointing toward the front, the fist can represent the brain’s left hemisphere as positioned within the skull and serve as a guide to its four major lobes (divisions) (Figure 1.1B). To help us tell the story of the brain in this chapter, it is helpful to learn some of the names that are given to parts of the brain. Figure 1.1 The Human Brain (A) The human brain, as oriented in the head. The visible part of the intact brain is the cerebral cortex, a thin sheet of tissue folded many times and fitting snugly inside the skull. If the brain is sectioned from left to right, the cortex can be seen to cover the brain’s internal structures. (B) Your right fist can serve as a guide to the orientation of the left hemisphere of the brain and its cerebral lobes. Each of its four major lobes is named after the skull bone under which it lies: occipital, parietal, temporal, and frontal. The brain’s basic plan is that of a tube of tissue called the neural tube, filled with salty fluid known as cerebrospinal fluid (CSF). CSF cushions the brain and assists in removing metabolic waste. Parts of the tube’s covering have bulged outward and folded, forming the more complicated-looking surface structures that initially catch the eye in Figure 1.1A. The brain’s most conspicuous outer feature is the crinkled tissue that has expanded from the front of the tube to such an extent that it folds over and covers much of the rest of the brain (Figure 1.1A at right). This outer layer is the neocortex (usually referred to as just the cortex). The word cortex, meaning “bark” in Latin, is apt, because the cortex’s folded appearance resembles the bark of a tree and because, as bark covers a tree, cortical tissue covers most of the rest of the brain. Neo signifies that this cortex is the most recently evolved part of the brain; beneath its folds are older cortical structures. The folds, or bumps, in the cortex are called gyri (gyrus is Greek for “circle”), and the creases between them are called sulci (sulcus is Greek for “trench”). Some large sulci are called fissures: the longitudinal fissure, shown in the Figure 1.1 frontal view, divides the two hemispheres; the lateral fissure divides each hemisphere into halves. (In our fist analogy, the lateral fissure is the crease separating the thumb from the other fingers.) Pathways called commissures, the largest of which is the corpus callosum, connect the brain’s hemispheres. The cortex of each hemisphere forms four lobes, each named after the skull bones beneath which they lie. The temporal lobe (the name derives from “time” because the side of the head is the first to gray with aging) lies below the lateral fissure at approximately the same place as the thumb on your upraised fist (Figure 1.1B). Immediately in front of the temporal lobe is the frontal lobe, so called because it is located at the front of the brain, beneath the frontal bones. The parietal lobe (parietal meaning “wall of a body”) is located behind the frontal lobe, and the occipital lobe (occipital meaning “back of the head”) constitutes the area at the back of each hemisphere. The cerebral cortex constitutes most of the forebrain, so named because it develops from the front part of the neural tube that makes up an embryo’s primitive brain. The remaining “tube” underlying the cortex is the brainstem. The brainstem is in turn connected to the spinal cord, which descends down the back within the vertebral column. To visualize the relationships among these parts of the brain, again imagine your upraised fist: the folded fingers represent the cortex, the heel of the hand represents the brainstem, and the arm represents the spinal cord. This three-part brain is conceptually useful evolutionarily, anatomically, and functionally for describing how the brain works. Evolutionarily, animals with only spinal cords preceded those with brainstems, which preceded those with forebrains. Anatomically, in prenatal development, the spinal cord forms before the brainstem, which forms before the forebrain. Functionally, the forebrain mediates what we call higher functions, such as executive and cognitive functions. The brainstem mediates regulatory functions such as eating, drinking, and moving; and the spinal cord conveys sensory information to the brain and sends commands from the brain to the muscles to move. We caution that these descriptions are generalizations, and the various divisions of the brain work together to produce most of our behavior, as will be clear as you read through this book. How Does the Brain Relate to the Rest of the Nervous System? Figure 1.2 diagrams the major divisions of the human nervous system. The brains and spinal cords of mammals are encased in protective bones: the skull protects the brain, and vertebrae protect the spinal cord. Together, the brain and spinal cord are called the central nervous system (CNS). Figure 1.2 Major Divisions of the Human Nervous System The brain and spinal cord together make up the CNS and the afferent and efferent pathways (entering and leaving pathways, respectively) make up the PNS. The nerve processes that connect us to the outside world comprise the SNS, and the nerve processes that connect us to our internal organs comprise the ANS. The CNS is connected to the rest of the body through nerve fibers. Some fibers carry information away from the CNS; others bring information into it. These nerve fibers constitute the peripheral nervous system (PNS). One distinguishing feature between the central and peripheral nervous systems is that PNS tissue regrows after damage, whereas the CNS does not regenerate lost tissue — a difference which serves as a clue to how damaged brain tissue could be replaced. At present, the long-term prospect for L.D. is that his recovery will never really be complete because the brain cells that he has lost due to TBI will not be replaced. The peripheral nervous system is divided into two parts, the somatic nervous system (SNS), which senses and responds to our external world, and the autonomic nervous system (ANS), which senses and responds to the body’s organs, or our internal world. Both the SNS and the ANS have two divisions, a sensory division and a motor division. Nerve fibers of the sensory division connect the sensory receptors, enabling the brain to sense the world in different ways. The nerve fibers of the motor division connect to our muscles and allow us to respond to sensory information. The sensory division of the SNS is organized into sensory pathways, collections of fibers that carry messages from our different senses, including our five major senses: sight, hearing, smell, taste, and body senses, such as touch, pressure, pain and temperature, and balance. Sensory pathways carry information collected on one side of the body mainly to the cortex in the opposite hemisphere. The brain uses this information to construct perceptions of the world, memories of past events, and expectations about the future. The motor division of the somatic system consists of motor pathways that produce our various movements, such as the eye movements that you are using to read this book, the hand movements that you make while turning or scrolling through the pages, and your body’s posture as you read. The ANS contains sensory and motor pathways that influence the muscles of our internal organs — the beating of the heart, contractions of the stomach, raising and lowering of the diaphragm to inflate and deflate the lungs. The sensory and motor pathways of the ANS have fewer connections with the CNS, which is why we are less aware and have less control over the function of our body’s organs. The organization of the sensory and motor pathways of the SNS reveal one of the major principles of brain function: each hemisphere largely senses our opposite sensory world and responds with muscles on the opposite side of the body. The term crossed brain is sometimes colloquially used to describe this brain organization with its many crossing sensory and motor pathways. 1.2 Perspectives on the Brain and Behavior The central topic in neuropsychology is how our brain and behavior are related. We begin with three classic theories — mentalism, dualism, and materialism — representative of the many attempts scientists and philosophers have made to relate brain and behavior. Then we explain why contemporary brain investigators subscribe to the materialist view. In reviewing these theories, you will recognize that some “commonsense” ideas you might have about behavior are derived from one or another of these perspectives (Finger, 1994). Aristotle: Mentalism The Greek philosopher Aristotle (384–322 B.C. E. ) was among the first philosophers to describe a formal theory of behavior. He proposed that a nonmaterial psyche is responsible for human thoughts, perceptions, and emotions and for such processes as imagination, opinion, desire, pleasure, pain, memory, and reason. The psyche is independent of the body, but Aristotle viewed it as working through the heart to produce action. As in Aristotle’s time, heart metaphors serve to this day to describe our behavior: “put your heart into it” and “she wore her heart on her sleeve” are but two. Aristotle’s view that this nonmaterial psyche governs behavior was adopted by Christianity in its concept of the soul and has been widely disseminated throughout the world. We still use psych, as in psychology, to label the study of behavior. The word psyche was translated into English as mind, the Anglo-Saxon word for memory. The philosophical position that a person’s mind is responsible for behavior is called mentalism, meaning “of the mind.” Mentalism still influences modern neuropsychology: many terms — sensation, perception, attention, imagination, emotion, memory, and volition among them — still employed as labels for patterns of behavior have their origin in concepts originally developed within mentalism. (Scan some of the chapter titles in this book.) Mentalism also influences people’s ideas about how the brain might work because the mind was proposed to be nonmaterial and to have no “working parts.” We use the term mind to describe our perceptions of ourselves as having unitary consciousness despite the fact that the brain is composed of many parts and has many separate functions, as we are learning. Many contemporary neuroscientists colloquially describe the goal of neuroscience as being to understand the mind (Gigerenzer, 2019). Descartes: Dualism René Descartes (1596–1650), a French anatomist and philosopher, wrote what could be considered the first neuropsychology text, Traité de L’Homme, which was published posthumously in 1664. He accepted the concept of mind but also gave the physical brain a prominent role in behavior. Descartes was impressed by machines made in his time, such as those encased in certain statues on display for public amusement in the water gardens of Paris. When a passerby stopped in front of one particular statue, for example, his or her weight depressed a lever under the sidewalk, causing the statue to move and spray water at the person’s face. Descartes proposed that the body is like these machines. It is material and thus clearly has spatial extent, and it responds mechanically and reflexively to events that impinge on it (Figure 1.3). Figure 1.3 Descartes’s Concept of Reflex Action In this mechanistic depiction, heat from the flame causes a thread in the nerve to be pulled, releasing ventricular fluid through an opened pore. The fluid flows through the nerve, causing not only the foot to withdraw but the eyes and head to turn to look at it, the hands to advance, and the whole body to bend to protect it. Descartes ascribed to reflexes behaviors that today are considered too complex to be reflexive, whereas he did not conceive of behavior described as reflexive today. Described as nonmaterial and without spatial extent, the mind, as Descartes saw it, was different from the body. The body operated on principles similar to those of a machine, but the mind decided what movements the machine should make. Descartes located the site of action of the mind in the pineal body, a small structure high in the brainstem. His choice was based on the logic that the pineal body is the only structure in the nervous system not composed of two bilaterally symmetrical halves and moreover that it is located close to the ventricles. His idea was that the mind, working through the pineal body, controlled valves that allowed CSF to flow from the ventricles through nerves to muscles, filling them and making them move. For Descartes, the cortex was not functioning neural tissue but a covering for the pineal body. People later argued against Descartes’s hypothesis by pointing out that no obvious changes in behavior occur when the pineal body is damaged. Today, the pineal body, now called the pineal gland, is known to influence daily and seasonal biorhythms. The cortex is central to understanding functions that Descartes attributed to a nonmaterial mind. Descartes’s position that mind and body are separate but can interact is called dualism, to indicate that behavior is caused by two things. Dualism originated a quandary known as the mind–body problem: according to Descartes, a person is capable of consciousness and rationality only because of having a mind, but how can a nonmaterial mind produce movements in a material body? To understand the mind–body problem, consider that for the mind to affect the body, it must expend energy, adding new energy to the material world. The spontaneous creation of new energy violates a fundamental law of physics: the law of conservation of matter and energy. Thus, dualists who argue that mind and body interact causally cannot explain how. Other dualists avoid this problem by reasoning either that the mind and body function in parallel, without interacting, or that the body can affect the mind, but the mind cannot affect the body. These dualist positions allow for both a body and a mind by sidestepping the problem of violating the laws of physics. Descartes’s theory also spawned unforeseen and unfortunate consequences. In proposing his dualistic theory of brain function, Descartes also proposed that animals do not have minds and therefore are only machinelike, that the mind develops with language in children, and that mental disease impairs rational processes of the mind. Some of his followers justified the inhumane treatment of animals, children, and the mentally ill on the grounds that they did not have minds: an animal did not have a mind, a child developed a mind only at about 7 years of age when able to talk and reason, and the mentally ill had “lost their minds.” Likewise misunderstanding Descartes’s position, some people still argue that the study of animals cannot be a source of useful insight into human neuropsychology. Descartes himself, however, was not so dogmatic. He was kind to his dog, Monsieur Grat. He suggested that whether animals had minds could be tested experimentally. He proposed that the key indications of the presence of a mind are the use of language and reason. He suggested that, if it could be demonstrated that animals could speak or reason, then such demonstration would indicate that they have minds. Exciting lines of research in modern experimental neuropsychology, demonstrated throughout this book, are directed toward the comparative study of animals and humans with respect to memory, language, and reason. Darwin: Materialism By the mid-nineteenth century, our contemporary perspective of materialism was taking shape. The idea is that rational behavior can be fully explained by the workings of the nervous system. According to materialism, there is no need to refer to a nonmaterial mind. Materialism has its roots in the evolutionary theories of two English naturalists, Alfred Russel Wallace (1823–1913) and Charles Darwin (1809–1892). Evolution by Natural Selection Darwin and Wallace examined the structures of plants and animals and animal behavior. Despite the diversity of living organisms, the two naturalists were struck by the many similarities between organisms. For example, the skeleton, muscles, internal organs, and nervous systems of humans, monkeys, and other mammals are similar. These observations support the idea that living things must be related, an idea widely held even before Wallace and Darwin. More importantly, these same observations led to the idea that the similarities could be explained if all animals had evolved from a common ancestor. Darwin elaborated his theory in On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life, originally published in 1859. He argued that all organisms, both living and extinct, are descended from an ancestor that lived in the remote past. Animals have similar traits because those traits are passed from parents to their offspring. The nervous system is one such trait, an adaptation that emerged only once in animal evolution. Consequently, the nervous systems of living animals are similar because they are descendants of that first nervous system. Those animals with brains likewise are related because all animals with brains descend from the first animal to evolve a brain. Natural selection is Darwin’s theory for explaining how new species evolve and how they change over time. A species is a group of organisms that can breed among themselves but usually not with members of other species. Individual organisms within a species vary in their phenotype, the traits we can see or measure. Some are big, some are small, some are fat, some are fast, some are light colored, some have large teeth. Individual organisms whose traits best help them to survive in their environment are likely to leave more offspring that feature those traits. Natural Selection and Heritable Factors Beginning about 1857, Gregor Mendel (1822–1884), an Austrian monk, experimented with plant traits, such as the flower color and height of pea plants, and determined that such traits are due to heritable factors we now call genes (elaborated in Section 2.3). Thus, the unequal ability of individual organisms to survive and reproduce is related to the different genes they inherit from their parents and pass on to their offspring. Genetics, the study of genes and their function, emerged from this insight. Mendel realized that the environment plays a role in how genes express traits: planting tall peas in poor soil reduces their height. Likewise, experience affects gene expression: children who lack educational opportunities may not adapt as well in society as children who attend school. A new field of study that explains how the environment influences behavior is epigenetics (see Section 2.3). One way that epigenetic factors affect behavior is that they influence whether a gene is active — turned on or off — and in this way influence an individual’s behavior. Environment and experience play an important role in how animals adapt and learn. Adaptation and learning are in turn enabled by the brain’s ability to form new connections and pathways. The theory of neuroplasticity, that the brain can physically and chemically change, directs research on the nervous system’s potential for changing to enhance its adaptability to the environment. Neuroplasticity also explains how the brain compensates for injury. Our golfer and cook L.D. was in a coma after his fall, but with time he recovered consciousness, and then he recovered his ability to move and, eventually, his previously acquired golfing skills — all because of neuroplastic changes in his nervous system. Contemporary Perspectives As a scientific theory, contemporary brain theory is both materialistic and neutral with respect to beliefs, including religious beliefs. Science is not a belief system but rather a set of procedures designed to allow investigators to confirm answers to questions. Behavioral scientists, both those with and those without religious beliefs, use the scientific method to examine relationships between the brain and behavior and to replicate (repeat) others’ work on brain–behavior relationships. Today, when neuroscientists use terms such as mind and consciousness, most are not referring to a nonmaterial entity but are using them as shorthand for the collective functions of the brain, as does Francis Crick, the co-discoverer of the DNA double helix, in his book on the search for the soul, The Astonishing Hypothesis. 1.3 Brain Function: Insights from Brain Injury You may have heard statements such as “Most people use only 10% of their brains.” This idea arises from early suggestions that people with brain damage often get along quite well. Nevertheless, for most people who endure brain damage, some behavior is lost and some survives, as it did for L.D., whose case begins this chapter. Our understanding of brain function has its origins in individuals with brain damage. We now describe some fascinating neuropsychological concepts that have emerged from studying such individuals. Localization of Function The first general theory to propose that different parts of the brain have different functions was developed in the early 1800s by German anatomist Franz Josef Gall (1758–1828) and his partner Johann Gaspar Spurzheim (1776– 1832) (Critchley, 1965). Gall and Spurzheim proposed that the cortex and its gyri were functioning parts of the brain and not just coverings for the pineal body. They supported their position by showing through dissection that the brain’s most distinctive motor pathway, the corticospinal (cortex to spinal cord) tract, leads from the cortex of each hemisphere to the spinal cord on the opposite side of the body. Thus, they suggested, the cortex sends instructions to the spinal cord to command muscles to move. They also recognized that the two symmetrical hemispheres of the brain are connected by the corpus callosum and can thus interact. Gall’s ideas about behavior began with an observation made in his youth. Reportedly, he observed that students with good memories had large, protruding eyes and surmised that a well-developed memory area of the cortex located behind the eyes would cause them to protrude. Thus, he developed his hypothesis, called localization of function, that a different, specific brain area controls each kind of behavior. Gall and Spurzheim furthered this idea by collecting instances of individual differences that they related to other prominent features of the head and skull. They proposed that a bump on the skull indicated a well-developed underlying cortical gyrus and therefore a greater capacity for a particular behavior; a depression in the same area indicated an underdeveloped gyrus and a concomitantly reduced faculty. Thus, just as a person with a good memory had protruding eyes, a person with a high degree of musical ability, artistic talent, sense of color, combativeness, or mathematical skill would have large bumps in other areas of the skull (see Figure 1.4 for an example). Figure 1.4 Gall’s Theory Depressions (A) and bumps (B) on the skull indicate the size of the underlying area of brain and thus, when correlated with personality traits, indicate the part of the brain controlling the trait. While examining a patient (who because of her behavior became known as “Gall’s Passionate Widow”), Gall found a bump at the back of her neck that he thought located the center for “amativeness” (sexiness) in the cerebellum. (Research from Olin, 1910.) A person with a bump there would be predicted to have a strong sex drive, whereas a person low in this trait would have a depression in the same region. Gall and Spurzheim identified a long list of behavioral traits borrowed from the English or Scottish psychology of the time. They assigned each trait to a particular part of the skull and, by inference, to the underlying brain part. Spurzheim called this study of the relation between the skull’s surface features and a person’s mental faculties phrenology (phren is a Greek word for “mind”). Figure 1.5 shows the resulting phrenological map that he and Gall devised. Figure 1.5 Phrenology Bust Originally, Gall’s system identified putative locations for 27 faculties. As the study of phrenology expanded, the number of faculties increased. Language, indicated at the front of the brain, below the eye, actually derived from one of Gall’s case studies. A soldier had suffered a knife wound that penetrated the frontal lobe of his left hemisphere through the eye. The soldier lost the ability to speak. Some people seized on phrenology as a means of making personality assessments. They developed a method called cranioscopy, in which a device was placed around the skull to measure its bumps and depressions. These measures were then correlated with the phrenological map to determine the person’s likely behavioral traits. Cranioscopy was even proposed as a method for determining a person’s fitness to attend university or to be given a job. As a science, phrenology was a flop; characteristics such as faith, self-love, and veneration are impossible to define and to quantify objectively. Phrenologists also failed to recognize that the superficial features on the skull reveal little about the underlying brain. Nevertheless, Gall’s notion of localization of function laid the conceptual foundation for modern views of functional localization, beginning with the localization of language. Among his many observations, Gall gave the first account of a case in which frontal-lobe brain damage was followed by loss of the ability to speak. The patient was a soldier whose brain was pierced by a sword driven through his eye. Note that, on the phrenological map in Figure 1.5, language is located below the eye. Gall gave the observation no special emphasis, thinking it merely a confirmation of his theory. The case subsequently came to factor in discoveries concerning the brain’s role in language. Lateralization of Function A now legendary chain of observations and speculations led to confirmation that language is both localized in the brain and lateralized — that is, located on one side of the brain. This discovery led to the principle of lateralization of function, that one cerebral hemisphere can perform a function not shared by the other (Benton, 1964). On February 21, 1825, French physician Jean Baptiste Bouillaud (1796–1881) read a paper before the Royal Academy of Medicine in France. Bouillaud argued from clinical studies that certain functions are localized in the cortex and, specifically, that speech is localized in the frontal lobes, in accordance with Gall’s theory. Observing that acts such as writing, drawing, painting, and fencing are carried out with the right hand, Bouillaud also suggested that the part of the brain that controls them might be the left hemisphere. Physicians had long recognized that damage to a hemisphere of the brain impairs movement of the opposite side of the body. A few years later, in 1836, Marc Dax (1770– 1837) presented a paper in Montpellier, France, discussing a series of clinical cases demonstrating that disorders of speech were constantly associated with lesions of the left hemisphere. Dax’s manuscript received little attention, however, and was not published until 1865, by his son. Ernest Auburtin (1825–1893), Bouillaud’s son-in-law, supported Bouillaud’s cause. At a meeting of the Anthropological Society of Paris in 1861, he reported the case of a patient who lost the ability to speak when pressure was applied to his exposed frontal lobe. Auburtin also described another patient, ending with a promise that other scientists interpreted as a challenge: For a long time during my service with M. Bouillaud I studied a patient, named Bache, who had lost his speech but understood everything said to him and replied with signs in a very intelligent manner to all questions put to him…. I saw him again recently and his disease has progressed; slight paralysis has appeared but his intelligence is still unimpaired, and speech is wholly abolished. Without a doubt this man will soon die. Based on the symptoms that he presents we have diagnosed softening of the anterior lobes. If, at autopsy, these lobes are found to be intact, I shall renounce the ideas that I have just expounded to you. (Stookey, 1954) Paul Broca (1824–1880), founder of the Anthropological Society, heard Auburtin’s challenge. Five days later he received a patient, a Monsieur Leborgne, who had lost his speech and was able to say only “tan” and utter an oath. The right side of his body was paralyzed, but he seemed intelligent and typical in other respects. Broca recalled Auburtin’s challenge and invited him to examine Tan, as the patient came to be called. Together they agreed that, if Auburtin was right, Tan should have a frontal lesion. Tan died on April 17, 1861, and the next day Broca (1960) submitted his findings to the Anthropological Society. (This submission is claimed to be the fastest publication ever made in science.) Auburtin was correct: the left frontal lobe was the focus of Tan’s lesion. By 1863, Broca had collected eight more cases similar to Tan’s, each with a frontal lobe lesion in the left hemisphere (Broca, 1865). As a result of his studies, Broca located speech in the third convolution (gyrus) of the frontal lobe on the left side of the brain (Figure 1.6). By demonstrating that speech is located only in one hemisphere, Broca discovered the brain property of functional lateralization. Because speech is thought to be central to human consciousness, the left hemisphere is referred to as the dominant hemisphere to recognize its special role in language (Joynt, 1964). In recognition of Broca’s contribution, the anterior speech region of the brain is called Broca’s area, and the syndrome that results from its damage is called Broca aphasia (from the Greek a, for “not,” and phasia, for “speech”). (As a note, contemporary terminology uses “Broca aphasia” to refer to the condition in which there is an inability to speak, “Broca’s aphasia” to refer to the one explanation for the condition, and “Broca’s area” to refer to the proposed anatomical location of speech. Similar terminology applies to “Wernicke aphasia,” “Wernicke’s aphasia,” and “Wernicke’s area,” described below.) Figure 1.6 CT Scan and Brain Reconstruction (A) Dorsal view of a horizontal CT scan of a subject with Broca aphasia. The dark region at the left anterior is the area of the lesion. (B) A schematic representation of the horizontal section, with the area of the lesion shown in blue. (C) A reconstruction of the brain, showing a lateral view of the left hemisphere with the lesion shown in blue. (Research from Damasio & Damasio, 1989) An interesting footnote: Broca examined Tan’s brain only by inspecting its surface. His anatomical analysis was criticized by French anatomist Pierre Marie (1906/1971), who reexamined the preserved brains of Broca’s first two patients, Tan and Monsieur Lelong, 25 years after Broca’s death. Marie pointed out in his article “The Third Left Frontal Convolution Plays No Particular Role in the Function of Language” that Lelong’s brain showed general nonspecific atrophy, common in senility, and that Tan had additional extensive damage in his posterior cortex that may have accounted for his aphasia. Broca was aware of Tan’s posterior damage but concluded that, whereas it contributed to his death, the anterior damage had occurred earlier, producing his aphasia. Broca’s view on localization and his discovery of lateralization became dogma in neuropsychology for the next 100 years, but it was tempered by Pierre Marie’s criticism. A Lateralized Language Model German anatomist Carl Wernicke (1848–1904) created the first model of how the brain produces language in 1874. Wernicke was aware that the part of the cortex into which the sensory pathway from the ear projects — the auditory cortex — is located in the temporal lobe behind Broca’s area. He therefore suspected a relationship between hearing and speech functioning, and he described cases in which aphasic patients had lesions in this auditory area of the temporal lobe. These patients displayed no opposite-side paralysis and they could speak fluently, but what they said was confused and made little sense. And although they could hear, they could neither understand nor repeat what was said to them. Wernicke syndrome is sometimes called temporal-lobe aphasia or fluent aphasia, to emphasize that the person can say words, but is more frequently called Wernicke aphasia. The associated region of the temporal lobe is called Wernicke’s area. By contrast, Broca aphasia is frequently associated with paralysis of the right arm and leg, as described for Tan, and although these patients could not articulate, they could understand the meanings of words. In short, the distinguishing features of the conditions in relation to language is that Broca aphasia patients have a movement problem, whereas Wernicke aphasia patients have a problem of understanding. Wernicke’s model of language organization in the left hemisphere is illustrated in Figure 1.7A. He proposed that auditory informati

Fundamentals of Human Neuropsychology, 8th Edition PDF

Document Details

Tags

Related

Summary

Full Transcript

Upgrade to continue