The Mind's Machine: Foundations of Brain and Behavior

Description

"The Mind's Machine, introduced in 2012, was written to present the interdisciplinary topics of introductory behavioral neuroscience to students from non-science majors, to psychology, life sciences, and neuroscience. This engaging and user-friendly text brings in relevance to students of all backgrounds through coverage of contemporary research, clinical cases and experimental studies, as well as through the use of clear learning objectives and concept checks, and Acrobatiq courseware for adaptive learning integrated with interactive learning tools"-- Cover Title Page Copyright Page Dedication Page Brief Contents Contents Preface Digital Resource Introduction Building the Mind’s Machine Behavioral Neuroscience Spans Past, Present, and Future An understanding of the brain’s role in behavior has developed over centuries Research objectives reflect specific theoretical orientations The future of behavioral neuroscience is in interdisciplinary discovery and knowledge translation Looking forward: A glimpse inside The Mind’s Machine Visual Summary 1: Structure and Function Neuroanatomy and Research Methods 1.1 The Nervous System Is Made of Specialized Cells The neuron has four principal divisions Information is transmitted through synapses The axon integrates and then transmits information Glial cells protect and assist neurons 1.2 The Nervous System Extends throughout the Body The peripheral nervous system has two divisions The central nervous system consists of the brain and spinal cord 1.3 The Brain Shows Regional Specialization of Functions The cerebral cortex performs complex cognitive processing Important nuclei are hidden beneath the cerebral cortex The midbrain has sensory and motor components The brainstem controls vital body functions Behaviors and cognitive processes depend on networks of brain regions 1.4 Specialized Support Systems Protect and Nourish the Brain The brain floats within layers of membranes The brain relies on two fluids for survival SIGNS & SYMPTOMS Stroke 1.5 Scientists Have Devised Clever Techniques for Studying the Structure and Function of the Nervous System Histological techniques let us view the cells of the nervous system in varying ways Brain-imaging techniques reveal the structure and function of the living brain RESEARCHERS AT WORK Subtractive analysis isolates specific brain activity 1.6 Careful Research Design Is Essential for Progress in Behavioral Neuroscience Three types of study designs probe brain-behavior relationships Animal research is an essential part of life sciences research, including behavioral neuroscience Behavioral neuroscientists use several levels of analysis Visual Summary 2: Neurophysiology The Generation, Transmission, and Integration of Neural Signals 2.1 Electrical Signals Are the Vocabulary of the Nervous System A threshold amount of depolarization triggers an action potential Ionic mechanisms underlie the action potential Action potentials are actively propagated along the axon BOX 2.1 How Is an Axon Like a Toilet? SIGNS & SYMPTOMS Multiple Sclerosis Synapses cause local changes in the postsynaptic membrane potential Spatial summation and temporal summation integrate synaptic inputs 2.2 Synaptic Transmission Requires a Sequence of Events Action potentials cause the release of transmitter molecules into the synaptic cleft Receptor molecules recognize transmitters The action of synaptic transmitters is stopped rapidly Neural circuits underlie reflexes 2.3 EEGs Measure Gross Electrical Activity of the Human Brain Electrical storms in the brain can cause seizures RESEARCHERS AT WORK Surgical probing of the brain revealed a map of the body Visual Summary 3: The Chemistry of Behavior Neurotransmitters and Neuropharmacology 3.1 Synaptic Transmission Is a Complex Electrochemical Process RESEARCHERS AT WORK The first transmitter to be discovered was acetylcholine 3.2 Neurotransmitter Substances Differ in Their Chemical Structure and in Their Distribution within the Brain The most abundant neurotransmitters are amino acids Four classical neurotransmitters modulate brain activity Many peptides function as neurotransmitters Some neurotransmitters are gases 3.3 Drugs Fit Like Keys into Molecular Locks Drugs are administered and eliminated in many different ways The effects of a drug depend on its dose Repeated treatments may reduce the effectiveness of drugs 3.4 Drugs Affect Each Stage of Neural Conduction and Synaptic Transmission Some drugs alter presynaptic processes Some drugs alter postsynaptic processes 3.5 Some Neuroactive Drugs Provide Relief from Mental Illness and Pain Antipsychotics relieve symptoms of schizophrenia Antidepressants reduce chronic mood problems Anxiolytics combat anxiety Opiates have powerful painkilling effects 3.6 Some Neuroactive Drugs Are Used to Alter Conscious Experience Cannabinoids have many effects Stimulants increase neural activity Alcohol acts as both a stimulant and a depressant Hallucinogens alter sensory perceptions 3.7 Substance Abuse and Addiction Are Global Social Problems Competing models of substance abuse have been proposed SIGNS & SYMPTOMS Medical Interventions for Substance Abuse Visual Summary 4: Development of the Brain 4.1 Growth and Development of the Brain Are Orderly Processes Development of the nervous system can be divided into six distinct stages Cell proliferation produces cells that become neurons or glia In the adult brain, newly born neurons aid learning The death of many neurons is a normal part of development 4.2 An Explosion of Synapse Formation Is Followed by Synapse Rearrangement Retaining too many synapses can impair intellectual development Visual deprivation can lead to blindness Early exposure to visual patterns helps fine-tune connections in the visual system 4.3 Experience Can Affect Brain Development by Altering Gene Expression Genotype is fixed at birth, but phenotype changes throughout life Experience regulates gene expression in the developing and mature brain RESEARCHERS AT WORK Maternal care affects mouse behaviors Gene expression in the brain can be affected by mothering 4.4 The Brain Continues to Change as We Grow Older Memory impairment correlates with hippocampal shrinkage during aging Alzheimer’s disease is associated with a decline in cerebral metabolism SIGNS & SYMPTOMS Imaging Alzheimer’s Plaques Visual Summary 5: The Sensorimotor System 5.1 Sensory Processing and the Somatosensory System Receptor cells detect various forms of energy Receptor cells convert sensory signals into electrical activity Sensory information processing is selective and analytical Sensory events are encoded as streams of action potentials Sensory neurons respond to stimuli falling in their receptive fields Successive levels of the CNS process sensory information Sensory brain regions influence one another and change over time 5.2 Pain: The Body’s Emergency Signaling System A discrete pain pathway projects from body to brain SIGNS & SYMPTOMS A Professional Eater Meets His Match Special neural pathways carry pain information to the brain Pain control can be difficult Analgesic drugs are highly effective Electrical stimulation can sometimes relieve pain Placebos effectively control pain in some people, but not all Activation of endogenous opioids relieves pain 5.3 Movement and the Motor System Muscles and the skeleton work together to move the body The spinal cord mediates “automatic” responses and receives inputs from the brain Motor cortex plans and executes movements—and more RESEARCHERS AT WORK Mirror neurons in premotor cortex track movements in others Extrapyramidal systems regulate and fine-tune motor commands Visual Summary 6: Hearing, Balance, Taste, and Smell 6.1 Hearing: Pressure Waves in the Air Are Perceived as Sound BOX 6.1 The Basics of Sound The external ear captures, focuses, and filters sound The middle ear concentrates sound energies The cochlea converts vibrational energy into neural activity RESEARCHERS AT WORK Georg von Békésy and the cochlear wave The hair cells transduce movements of the basilar membrane into electrical signals Auditory signals run from cochlea to cortex 6.2 Specialized Neural Systems Extract Information from Auditory Signals The pitch of sounds is encoded in two complementary ways Brainstem systems compare the ears to localize sounds The auditory cortex processes complex sound 6.3 Hearing Loss Is a Widespread Problem SIGNS & SYMPTOMS Restoring Auditory Stimulation in Deafness 6.4 Balance: The Inner Ear Senses the Position and Movement of the Head Some forms of vestibular excitation produce motion sickness 6.5 Taste: Chemicals in Foods Are Perceived as Tastes Tastes excite specialized receptor cells on the tongue The five basic tastes are signaled by specific sensors on taste cells Taste information is transmitted to several parts of the brain 6.6 Smell: Chemicals in the Air Elicit Odor Sensations The sense of smell starts with receptor neurons in the nose Olfactory information projects from the olfactory bulbs to several brain regions Many vertebrates possess a vomeronasal system Visual Summary 7: Vision From Eye to Brain 7.1 The Vision Pathway Extends from the Eye to the Brain Visual processing begins in the retina Photoreceptors respond to light by releasing less neurotransmitter Different mechanisms enable the eyes to work over a wide range of light intensities Acuity is best in foveal vision Neural signals travel from the retina to several brain regions The retina projects to the brain in a topographic fashion 7.2 Neurons at Different Levels of the Visual System Have Very Different Receptive Fields Neurons in the retina and the LGN have concentric receptive fields RESEARCHERS AT WORK Neurons in the visual cortex have varied receptive fields Spatial-frequency analysis is unintuitive but efficient Neurons in the visual cortex beyond area V1 have complex receptive fields and help identify forms Visual perception of motion is analyzed by a special system that includes cortical area V5 7.3 Color Vision Depends on Integrating Information from the Retinal Cones Color perception requires receptor cells that differ in their sensitivities to different wavelengths SIGNS & SYMPTOMS Most Mammalian Species Have Some Color Vision Some retinal ganglion cells and LGN cells show spectral opponency Some visual cortical cells and regions appear to be specialized for color perception 7.4 What versus Where: Cortical Visual Areas Are Organized into Two Streams Visual neuroscience can be applied to alleviate some visual deficiencies SIGNS & SYMPTOMS Macular Degeneration Is the Leading Cause of Vision Loss as We Age Visual Summary 8: Hormones and Sex 8.1 Hormones Act in a Great Variety of Ways throughout the Body RESEARCHERS AT WORK Our current understanding of hormones developed in stages Hormones are one of several types of chemical communication Hormones can be classified by chemical structure Hormones act on a wide variety of cellular mechanisms Hormones can have different effects on different target organs Box 8.1 Techniques of Behavioral Endocrinology Each endocrine gland secretes specific hormones The posterior pituitary releases two hormones directly into the bloodstream Posterior pituitary hormones can affect social behavior Feedback control mechanisms regulate the secretion of hormones Hypothalamic releasing hormones govern the anterior pituitary Two anterior pituitary tropic hormones act on the gonads The gonads produce steroid hormones, regulating reproduction Hormonal and neural systems interact to produce integrated responses 8.2 Reproductive Behavior Is Regulated by the Brain Copulation brings gametes together Gonadal steroids activate sexual behavior RESEARCHERS AT WORK Individual differences in mating behavior Estrogen and progesterone act on a lordosis circuit that spans from brain to muscle Androgens act on a neural system for male reproductive behavior Maternal behaviors are governed by several sex-related hormones The hallmark of human sexual behavior is diversity Hormones play only a permissive role in human sexual behavior 8.3 Genetic and Hormonal Mechanisms Guide the Development of Masculine and Feminine Structures Sex chromosomes direct sexual differentiation of the gonads Gonadal hormones direct sexual differentiation of the body Changes in sexual differentiation processes result in predictable changes in development Reduced androgen signaling can block masculinization of the body SIGNS & SYMPTOMS Defining an Athlete’s Sex How should we define sex—by genes, gonads, genitals? RESEARCHERS AT WORK Gonadal hormones direct sexual differentiation of behavior and the brain Early testicular secretions result in masculine behavior in adulthood Several regions of the nervous system display prominent sexual dimorphism Social influences also affect sexual differentiation of the nervous system Do fetal hormones masculinize human behaviors in adulthood? What determines a person’s sexual orientation? Visual Summary 9: Homeostasis Active Regulation of the Internal Environment 9.1 Homeostatic Systems Share Several Key Features Negative feedback allows precise control Redundancy ensures critical needs are met Animals use behavioral compensation to adjust to environmental changes 9.2 The Body’s Water Is Actively Balanced between Two Major Compartments Osmotic thirst occurs when the extracellular fluid becomes too salty Hypovolemic thirst is triggered by a loss of fluid volume We don’t stop drinking just because the throat and mouth are wet 9.3 Our Bodies Regulate Energy Balance and Nutrient Intake to Serve Current Needs and Prepare for Future Demands Insulin is essential for obtaining, storing, and using food energy 9.4 The Hypothalamus Coordinates Multiple Systems That Control Hunger RESEARCHERS AT WORK Lesion studies showed that the hypothalamus is crucial for appetite Hormones from the body drive a hypothalamic appetite controller Other systems also play a role in hunger and satiety SIGNS & SYMPTOMS Friends with Benefits 9.5 Obesity and Eating Disorders Are Difficult to Treat Eating disorders can be life-threatening Visual Summary 10: Biological Rhythms and Sleep 10.1 Biological Rhythms Organize Behavior Circadian rhythms are generated by an endogenous clock The hypothalamus houses a circadian clock RESEARCHERS AT WORK Transplants prove that the SCN produces a circadian rhythm In mammals, light information from the eyes reaches the SCN directly Circadian rhythms have been genetically dissected in flies and mice 10.2 Sleep Is an Active Process Human sleep exhibits different stages We do our most vivid dreaming during REM sleep Different species provide clues about the evolution of sleep 10.3 Our Sleep Patterns Change across the Life Span Most people sleep appreciably less as they age Manipulating sleep reveals an underlying structure Sleep recovery may take time SIGNS & SYMPTOMS Total Sleep Deprivation Can Be Fatal What are the biological functions of sleep? Some humans sleep remarkably little, yet function normally RESEARCHERS AT WORK The forebrain generates slow wave sleep At least four interacting neural systems underlie sleep The reticular formation wakes up the forebrain The pons triggers REM sleep 10.4 Sleep Disorders Can Be Serious, Even Life-Threatening A hypothalamic sleep center was revealed by the study of narcolepsy Some minor dysfunctions are associated with non-REM sleep Some people appear to be acting out their nightmares Insomniacs have trouble falling asleep or staying asleep Although many drugs affect sleep, there is no perfect sleeping pill Everyone should practice good sleep hygiene Visual Summary 11: Emotions, Aggression, and Stress 11.1 Theories of Emotion Integrate Physiological and Behavioral Processes Do emotions cause bodily changes, or vice versa? RESEARCHERS AT WORK Do we use context to attribute specific emotions to physiological arousal? SIGNS & SYMPTOMS Lie Detector? Is there a core set of emotions? Facial expressions have complex functions in communication Facial expressions are mediated by muscles, cranial nerves, and CNS pathways 11.2 Do Distinct Brain Circuits Mediate Different Emotions? Brain lesions also affect emotions The amygdala is crucial for emotional learning Different emotions activate different regions of the human brain 11.3 Neural Circuitry, Hormones, and Synaptic Transmitters Mediate Violence and Aggression Androgens seem to increase aggression Brain circuits mediate aggression The biopsychology of human violence is a controversial topic 11.4 Stress Activates Many Bodily Responses The stress response progresses in stages There are individual differences in the stress response Stress and emotions affect our health SIGNS & SYMPTOMS Long-Term Consequences of Childhood Bullying Why does chronic stress suppress the immune system? Visual Summary 12:Psychopathology The Biology of Behavioral Disorders 12.1 The Toll of Psychiatric Disorders Is Huge Schizophrenia is a major neurobiological challenge in psychiatry Schizophrenia has a heritable component RESEARCHERS AT WORK Stress increases the risk of schizophrenia An integrative model of schizophrenia emphasizes the interaction of factors The brains of some people with schizophrenia show structural and functional changes The severity of schizophrenia led to desperate treatment attempts Antipsychotic medications revolutionized the treatment of schizophrenia SIGNS & SYMPTOMS Long-Term Effects of Antipsychotic Drugs 12.2 Mood Disorders Are the Most Common Psychopathologies Inheritance is an important determinant of depression The brain changes with depression A wide variety of treatments are available for depression SIGNS & SYMPTOMS Mixed Feelings about SSRIs Why do more females than males develop depression? Scientists are still searching for animal models of depression Sleep characteristics change in affective disorders In bipolar disorder, mood cycles between extremes RESEARCHERS AT WORK The entirely accidental discovery of lithium therapy 12.3 There Are Several Types of Anxiety Disorders Drug treatments provide clues to the mechanisms of anxiety In post-traumatic stress disorder, horrible memories won’t go away In obsessive-compulsive disorder, thoughts and acts keep repeating SIGNS & SYMPTOMS Tics, Twitches, and Snorts: The Unusual Character of Tourette’s Syndrome Visual Summary 13: Memory and Learning 13.1 There Are Several Kinds of Learning and Memory For Patient H.M., the present vanished into oblivion RESEARCHERS AT WORK Which brain structures are important for declarative memory? Damage to the medial diencephalon can also cause amnesia Brain damage can destroy autobiographical memories while sparing general memories 13.2 Different Forms of Nondeclarative Memory Involve Different Brain Regions Different types of nondeclarative memory serve varying functions Animal research confirms the various brain regions involved in different attributes of memory Brain regions involved in learning and memory: A summary Successive processes capture, store, and retrieve information in the brain SIGNS & SYMPTOMS Emotions and Memory Long-term memory has vast capacity but is subject to distortion 13.3 Memory Storage Requires Physical Changes in the Brain Plastic changes at synapses can be physiological or structural Varied experiences and learning cause the brain to change and grow Invertebrate nervous systems show synaptic plasticity Classical conditioning relies on circuits in the mammalian cerebellum 13.4 Synaptic Plasticity Can Be Measured in Simple Hippocampal Circuits NMDA receptors and AMPA receptors collaborate in LTP Is LTP a mechanism of memory formation? Visual Summary 14: Attention and Higher Cognition 14.1 Attention Focuses Cognitive Processing on Specific Objects There are limits on attention Attention is deployed in several different ways RESEARCHERS AT WORK Reaction times reflect brain processing, from input to output Some types of stimuli just grab our attention Attention helps us to search for specific objects in a cluttered world 14.2 Targets of Attention: Attention Alters the Functioning of Many Brain Regions Distinctive patterns of brain electrical activity mark shifts of attention Attention affects the activity of neurons 14.3 Sources of Attention: A Network of Brain Sites Creates and Directs Attention Two subcortical systems guide shifts of attention Several cortical areas are crucial for generating and directing attention Brain disorders can cause specific impairments of attention SIGNS & SYMPTOMS Difficulty with Sustained Attention Can Sometimes Be Relieved with Stimulants 14.4 Consciousness, Thought, and Decisions Are Mysterious Products of the Brain Which brain regions are active when we are conscious? Some aspects of consciousness are easier to study than others A flexible frontal system plans and monitors our behavior We make decisions using a frontal network that weighs risk and benefit Visual Summary 15: Language and Lateralization 15.1 The Left and Right Hemispheres of the Brain Are Different The two hemispheres process information differently in most people The left and right hemispheres differ in their auditory specializations Handedness is associated with cerebral lateralization RESEARCHERS AT WORK Reversibly shutting down one hemisphere reveals its specializations 15.2 Right-Hemisphere Damage Impairs Specific Types of Cognition In prosopagnosia, faces are unrecognizable 15.3 Left-Hemisphere Damage Can Cause Aphasia Damage to a left anterior speech zone causes nonfluent (or Broca’s) aphasia Damage to a left posterior speech zone causes fluent (or Wernicke’s) aphasia Widespread left-hemisphere damage can obliterate language capabilities Competing models describe the left-hemisphere language network Brain mapping helps us understand the organization of language in the brain RESEARCHERS AT WORK Noninvasive stimulation mapping reveals details of the brain’s language areas Functional neuroimaging technologies let us visualize activity in the brain’s language zones during speech 15.4 Human Languages Share Basic Features Language has both unlearned and learned components Nonhuman primates engage in elaborate vocal behavior Many different species engage in vocal communication Some people struggle throughout their lives to read Brain damage may cause specific impairments in reading 15.5 Recovery of Function after Brain Damage: Stabilization and Reorganization Are Crucial Stages Rehabilitation and retraining can help recovery from brain and spinal cord injury SIGNS & SYMPTOMS Contact Sports Can Be Costly Visual Summary APPENDIX A: Primer on Concepts and Techniques in Molecular Biology A.1 Genes Carry Information That Encodes Proteins Genetic information is stored in molecules of DNA DNA is transcribed to produce messenger RNA RNA molecules direct the formation of protein molecules A.2 Molecular Biologists Have Craftily Enslaved Microorganisms and Enzymes Southern blots identify particular genes Northern blots identify particular mRNA transcripts In situ hybridization localizes mRNA transcripts within specific cells Western blots identify particular proteins Antibodies can also tell us which cells possess a particular protein Glossary References Index