* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download what is psychology
Survey
Document related concepts
Transcript
AP Psychology review for the AP exam Step 1: review all vocabulary terms!!!! Step 2: Read and reflect on the following unit summaries Step 3: Breathe: It’ll be okay… you know more than you think!!! I. History and Approaches (2–4%) II. Research Methods (6–8%) III. Biological Bases of Behavior (8–10%) IV. Sensation and Perception (7–9%) V. States of Consciousness (2–4%) VI. Learning (7–9%) VII. Cognition (8–10%) VIII. Motivation and Emotion (7–9%) IX. Developmental Psychology (7–9%) X. Personality (6–8%) XI. Testing and Individual Differences (5–7%) XII. Abnormal Psychology (7–9%) XIII. Treatment of Psychological Disorders (5–7%) XIV. Social Psychology (7–9%) WHAT IS PSYCHOLOGY? Psychology’s Roots Psychology traces its roots back through recorded history to the writings of many scholars who spent their lives wondering about people—in India, China, the Middle East, and Europe. In their attempt to understand human nature, they looked carefully at how our minds work and how our bodies relate to our minds. Prescientific Psychology More than 2000 years ago, Buddha and Confucius focused on the power and origins of ideas. In other parts of the world, the ancient Hebrews, Socrates, his student Plato, and Plato’s student Aristotle pondered whether mind and body are connected or distinct, and whether human ideas are innate or result from experience. In the 1700s, René Descartes and John Locke reengaged aspects of those ancient debates, and Locke coined his famous description of the mind as a "white paper." Psychological Science Is Born Psychology as we know it today was born in a laboratory in Germany in the late 1800s, when Wilhelm Wundt ran the first true experiments in psychology’s first lab. Soon, the new discipline formed branches: structuralism, which searched for the basic elements of the mind, and functionalism, which tried to explain why we do what we do. William James, a pragmatist and functionalist, wrote the first text for the new discipline. Psychological Science Develops After beginning as a "science of mental life," psychology evolved in the 1920s into a "science of observable behavior." After rediscovering the mind in the 1960s, psychology now views itself as a "science of behavior and mental processes." Psychology is growing and globalizing, as psychologists in 69 countries around the world work, teach, and do research. Contemporary Psychology Psychology’s Perspectives Psychologists view behavior and mental processes from various perspectives. These viewpoints are complementary, not contradictory, and each offers useful insights in the study of behavior and mental processes. Psychology’s Subfields Psychology’s subfields encompass basic research (often done by biological, developmental, cognitive, personality, and social psychologists), applied research (sometimes conducted by industrial/organizational psychologists), and clinical applications. Psychology’s methods and findings aid other disciplines, and they contribute to the growing knowledge base we apply in our everyday lives. WHY DO PSYCHOLOGY? What About Intuition and Common Sense? Although in some ways we outsmart the smartest computers, our intuition often goes awry. To err is human. Without scientific inquiry and critical thinking we readily succumb to hindsight bias, also called the I-knew-it-all-along phenomenon. Learning the outcome of a study (or of an everyday happening) can make it seem like obvious common sense. We also are routinely overconfident of our judgments, thanks partly to our bias to seek information that confirms them. Such biases lead us to overestimate our unaided intuition. Enter psychological science. Science, with its procedures for gathering and sifting evidence, restrains error. Although limited by the testable questions it can address, a scientific approach helps us sift reality from illusion, taking us beyond the limits of our intuition and common sense. The Scientific Attitude and Critical Thinking Scientific inquiry begins with an attitude—a curious eagerness to skeptically scrutinize competing ideas and an openminded humility before nature. Putting ideas, even crazy-sounding ideas, to the test helps us winnow sense from nonsense. The curiosity that drives us to test ideas and to expose their underlying assumptions carries into everyday life as critical thinking. HOW DO PSYCHOLOGISTS ASK AND ANSWER QUESTIONS? The Scientific Method Research stimulates the construction of theories, which organize observations and imply predictive hypotheses. These hypotheses (predictions) are then tested to validate and refine the theory and to suggest practical applications. Description The Case Study, the Survey, and Naturalistic Observation Through individual case studies, surveys among random samples of a population, and naturalistic observations, psychologists observe and describe behavior and mental processes. In generalizing from observations, remember: Representative samples are a better guide than vivid examples. Correlation Correlation and Causation The strength of the relationship between one factor and another is expressed as a number in their correlation coefficient. Scatterplots and the correlations they reveal help us to see relationships that the naked eye might miss. Knowing how closely two things are positively or negatively correlated tells us how much one predicts the other. But it is crucial to remember that correlation is a measure of relationship; it does not reveal cause and effect. Illusory Correlations and Perceiving Order in Random Events Correlations also help us to discount relationships that do not exist. Illusory correlations—random events we notice and assume are related—arise from our search for patterns. Experimentation To discover cause-and-effect relationships, psychologists conduct experiments. By constructing a controlled reality, experimenters can manipulate one or more factors and discover how these independent variables affect a particular behavior, the dependent variable. Evaluating Therapies, and Can Subliminal Tapes Improve Your Life? In many experiments, control is achieved by randomly assigning people either to the experimental condition, the group exposed to the treatment, or to a control condition, a group that experiences no treatment or a different version of the treatment. FREQUENTLY ASKED QUESTIONS ABOUT PSYCHOLOGY Can Laboratory Experiments Illuminate Everyday Life? By intentionally creating a controlled, artificial environment in the lab, researchers aim to test theoretical principles. These principles help us to understand, describe, explain, and predict everyday behaviors. Does Behavior Depend on One’s Culture and Gender? Attitudes and behaviors do vary between genders and across cultures, but the principles that underlie them vary much less. Cross-cultural psychology explores both our cultural differences and the universal similarities that define our human kinship. Why Do Psychologists Study Animals? Some psychologists study animals out of an interest in animal behavior. Others do so because knowledge of the physiological and psychological processes of animals gives them a better understanding of the similar processes operating in humans. Is It Ethical to Experiment on Animals? Only about 7 percent of all psychological experiments involve animals, and under ethical and legal guidelines these animals rarely experience pain. Nevertheless, animal rights groups raise an important issue: Even if it leads to the relief of human suffering, is an animal’s temporary suffering justified? Is It Ethical to Experiment on People? Occasionally researchers temporarily stress or deceive people in order to learn something important. Professional ethical standards provide guidelines concerning the treatment of both human and animal participants. Is Psychology Free of Value Judgments? Psychology is not value-free. Psychologists’ own values influence their choice of research topics, their theories and observations, their labels for behavior, and their professional advice. Is Psychology Potentially Dangerous? Knowledge is power that can be used for good or evil. Applications of psychology’s principles have so far been overwhelmingly for the good. Psychology addresses some of humanity’s greatest problems and deepest longings. TIPS FOR STUDYING PSYCHOLOGY How can psychological principles help you as a student? 1. Distribute your study time. 2. Learn to think critically. 3. In class, listen actively. 4. Overlearn. 5. Be a smart test-taker. ___NEURAL COMMUNICATION The body’s circuitry, the nervous system, consists of billions of individual cells called neurons. A neuron receives signals from other neurons through its branching dendrites and cell body, combines these signals in the cell body, and transmits an electrical impulse (the action potential) down its axon. When these signals reach the end of the axon, they stimulate the release of chemical messengers called neurotransmitters. These molecules pass on their excitatory or inhibitory messages as they traverse the synaptic gap between neurons and combine with receptor sites on neighboring neurons. Researchers are studying neurotransmitters to discern their role in behavior and emotion. Some drugs (agonists) excite by mimicking particular neurotransmitters or blocking their reuptake; others (antagonists) inhibit by blocking neurotransmiters. THE NERVOUS SYSTEM The central nervous system’s neurons in the brain and spinal cord communicate with the peripheral nervous system’s sensory and motor neurons. The peripheral nervous system has two main divisions. The somatic nervous system directs voluntary movements and reflexes. The autonomic nervous system, through its sympathetic and parasympathetic divisions, controls our involuntary muscles and glands. Like people clustering into neighborhoods, neurons cluster into working networks. THE BRAIN Clinical observations have long revealed the general effects of damage to various areas of the brain. But CT and MRI scans now reveal brain structures, and EEG, PET, and functional MRI recordings reveal brain activity. By surgically lesioning or electrically stimulating specific brain areas, by recording the brain’s surface electrical activity, and by displaying neural activity with computer-aided brain scans, neuroscientists explore the connections among brain, mind, and behavior. Lower-Level Brain Structures The brainstem begins where the spinal cord swells to form the medulla, which controls heartbeat and breathing. Within the brainstem, the reticular formation controls arousal. Atop the brainstem is the thalamus, the brain’s sensory switchboard. The cerebellum, attached to the rear of the brainstem, coordinates muscle movement. Between the brainstem and cerebral cortex is the limbic system, which is linked to memory, emotions, and drives. One of its neural centers, the amygdala, is involved in responses of aggression and fear. Another, the hypothalamus, is involved in various bodily maintenance functions, pleasurable rewards, and the control of the hormonal system. The Cerebral Cortex Each hemisphere of the cerebral cortex—the neural fabric that covers the hemispheres—has four geographic areas: the frontal, parietal, occipital, and temporal lobes. Small, well-defined regions within these lobes control muscle movement and receive information from the body senses. However, most of the cortex—its association areas—is uncommitted to such functions and is therefore free to process other information. Some brain regions serve specific functions (figure 2.30, page 94). The brain divides its labor into specialized subtasks and then integrates the various outputs from its neural networks. Thus, our emotions, thoughts, and behaviors result from the intricate coordination of many brain areas. Language, for example, depends on a chain of events in several brain regions. If one hemisphere is damaged early in life, the other will pick up many of its functions, thus demonstrating the brain’s plasticity. BRAIN REORGANIZATION Our Ever-Changing Brain If one hemisphere is damaged early in life (in the first five years), the other will pick up many of its functions, thus demonstrating the brain’s plasticity. Although the brain is less plastic later in life, nearby neurons may partially compensate for damaged ones, as when a patient recovers from a minor stroke. Our Divided Brain Clinical observations long ago revealed that the left cerebral hemisphere is crucial for language. Experiments on people with a severed corpus callosum have refined our knowledge of each hemisphere’s special functions. Separately testing the two hemispheres, researchers have confirmed that in most people the left hemisphere is the more verbal, and that the right hemisphere excels in visual perception and the recognition of emotion. Studies of healthy people with intact brains confirm that each hemisphere makes unique contributions to the integrated functioning of the brain. THE ENDOCRINE SYSTEM This chapter has focused on the body’s speedy electrochemical information system. There is, however, another communication system. Hormones released by the endocrine glands form the body’s slower information system. GENES: OUR BIOLOGICAL BLUEPRINT Genes (DNA segments that form the chromosomes) are the biochemical units of heredity. They provide the blueprint for protein molecules, the building blocks of our physical and behavioral development. EVOLUTIONARY PSYCHOLOGY: MAXIMIZING FITNESS Evolutionary psychologists study how natural selection has shaped our universal behavior tendencies. They reason that if organisms vary, if only some mature to produce surviving offspring, and if certain inherited behavior tendencies assist that survival, then nature must select those tendencies. They believe this helps explain gender differences in sexuality. Critics maintain that evolutionary psychologists make too many hindsight explanations. BEHAVIOR GENETICS: PREDICTING INDIVIDUAL DIFFERENCES Behavior geneticists explore our individual differences. Using methods such as twin, adoption, and temperament studies, they identify the heritability of various traits and disorders. Studies of the inheritance of temperament, and of twins and adopted children, provide scientific support for the idea that nature and nurture influence one’s developing personality. Genes and environment, biological and social factors, direct our life courses as their effects intertwine. Molecular geneticists are on a fast-moving frontier in their work to identify the specific genes that influence behaviors. ENVIRONMENTAL INFLUENCE Genetic influences are pervasive, but so are prenatal environments, early experiences, peer influences, and cultures. Sculpted by experience, neural interconnections multiply rapidly after birth. Human variations across cultures and over time show how differing norms, or expectations, guide behavior. Cultures differ in their norms for personal space, expressiveness, and pace of life. THE NATURE AND NURTURE OF GENDER Although males and females share similarly adaptive bodily procedures, differing sex chromosomes and differing concentrations of sex hormones lead to significant physiological sex differences. Yet gender differences vary widely depending upon cultural socialization through social learning and gender schemas. PRENATAL DEVELOPMENT AND THE NEWBORN Conception and Prenatal Development Developmental psychologists examine how we develop physically, cognitively, and socially, from conception to death. The life cycle begins when one sperm cell, out of the some 200 million ejaculated, unites with an egg to form a zygote. Attached to the uterine wall, the developing embryo begins to form body organs. By the ninth week, the fetus becomes recognizably human. The mother eats, drinks, and breathes for two, so that any teratogens she ingests can reach the developing child and place it at risk. The Competent Newborn Using new methods, researchers have discovered that newborns are born with sensory equipment and reflexes that facilitate their interacting with adults and securing nourishment. For example, they quickly learn to discriminate the smell and sound of their mothers. INFANCY AND CHILDHOOD Physical Development Brain Development Within the brain, nerve cells form before birth. Sculpted by maturation and experience, their interconnections multiply rapidly after birth. We lose conscious memories of experiences from our earliest years. Experiments do, however, show that infants can retain learning over time. Motor Development Infants’ more complex physical skills—sitting, standing, walking—develop in a predictable sequence whose actual timing is a function of individual maturation rate and culture. Cognitive Development Jean Piaget’s observations of children convinced him—and almost everyone else—that the mind of the child is not that of a miniature adult. Piaget theorized that our mind develops by forming schemas that help us assimilate our experiences and that must occasionally be altered to accommodate new information. In this way, children progress from the simplicity of the sensorimotor stage in the first two years to more complex stages of thinking, which include a developing "theory of mind." Piaget believed that preschool children, in the preoperational stage, are egocentric and unable to perform simple logical operations. At about age 6 or 7 they enter the concrete operational stage and can perform concrete operations, such as those required to comprehend the principle of conservation. Finally, at about age 12, children enter the formal operational stage, in which abstract reasoning is within their grasp. Recent research indicates that human cognition, regardless of culture, tends to unfold basically in the sequence Piaget proposed. However, young children are more capable, and development more continuous, than Piaget believed. The cognitive abilities that emerge at each stage apparently begin developing in a rudimentary form in the previous stage. Social Development Origins of Attachment and Deprivation of Attachment Attachment style in infancy predicts later social development. Infants become attached to their mothers and fathers not simply because mothers and fathers gratify biological needs but, more importantly, because they are comfortable, familiar, and responsive. If denied such care, both monkey and human infants may become pathetically withdrawn, anxious, and eventually abusive. Once an attachment forms, infants who are separated from their caregivers will, for a time, be distressed. Self-Concept and Child-Rearing Practices As with cognitive abilities, a self-concept develops gradually. By 18 months, infants recognize themselves in a mirror. By age 8 or 10, children’s self-images are quite stable and are linked with their independence, optimism, and sociability. Children who develop a positive self-image and a happy, self-reliant manner tend to have been reared by parents who are neither permissive nor authoritarian, but authoritative while allowing their children a sense of control. The parentingcompetence link is, however, correlational and does not explain cause and effect. ADOLESCENCE Physical Development Due to earlier maturation and prolonged education, adolescence—the transition years between biological maturity and social independence—has lengthened in many countries. Adolescence begins with a growth spurt that heralds the period of sexual maturation we call puberty and ends with the achievement of adult independence. Depending on how other people react, early or late maturation can influence adjustment, again illustrating how our genes and our environment interact in shaping us. Cognitive Development Piaget theorized that adolescents develop the capacity for formal operations, which enables them to reason abstractly. Today’s developmentalists find the rudiments of formal logic appearing earlier than Piaget believed. Following Piaget’s lead, Lawrence Kohlberg contended that moral thinking likewise proceeds through a sequence of stages, from a preconventional morality of self-interest, to a conventional morality concerned with gaining others’ approval or doing one’s duty, to (in some people) a postconventional morality of agreed-upon rights or universal ethical principles. But morality also lies in actions, which are influenced by the social situation and inner attitudes as well as by moral reasoning. Moreover, say Kohlberg’s critics, the postconventional level represents morality from the perspective of individualist, liberal-minded males. The social intuitionist perspective on morality suggests that moral feelings may precede moral judgments and influence our actions. Social Development Erik Erikson theorized that a chief task of adolescence is solidifying one’s sense of self—one’s identity. For many people, this struggle continues into the adult years as new relationships emerge and new roles are assumed. Although adolescence has traditionally been viewed as a time of storm and stress, researchers have found that most teenagers relate to their parents reasonably well and generally affirm their parents’ beliefs and attitudes. Gender differences in connectedness and other traits tend to peak during late adolescence and early adulthood. ADULTHOOD During early life, we sail a narrow channel, constrained by biological maturation. As the years pass, the channel widens, allowing us to diverge more and more. By adulthood, age no longer neatly predicts a person’s life experience and traits. Yet in some ways our bodies, minds, and relationships still undergo predictable changes. As long as we live, we adapt. Physical Development The barely perceptible physical declines of early adulthood begin to accelerate during middle adulthood. For women, a significant physical change is menopause, which generally seems to be a smooth rather than rough transition. For both men and women perceptual acuity, strength, and stamina decline after 65, but short-term ailments are fewer. Neural processes slow, and except for those who suffer brain disease, such as the progressive deterioration of Alzheimer’s disease, the brain remains healthy. Cognitive Development As the years pass, recognition memory remains strong, although recall begins to decline, especially for meaningless information. Research on how intelligence changes with age has progressed through several phases: cross-sectional studies suggesting a steady intellectual decline after early adulthood; longitudinal studies suggesting intellectual stability until very late in life; and today’s view that fluid intelligence declines in later life, but crystallized intelligence does not. Social Development From close study of small samples of individuals, some theorists maintain that adults pass through an orderly sequence of life stages. Some theorists have contended that moving from one stage to the next entails recurring times of crisis, such as the transition to midlife during the early forties. But people are not so predictable. Adult life is influenced in unanticipated ways, not only by events involving love and work but also by chance occurrences. Since 1960, marriage has been in decline, as reflected in later marriages, increased cohabitation, and doubled divorce rates. Although few people grow old gratefully, most age gracefully, retaining a sense of well-being throughout life. Those who live to old age must, however, cope with the deaths of friends and family members and with the prospect of their own deaths. Our experience with death is influenced by our experiences in life. REFLECTIONS ON TWO MAJOR DEVELOPMENTAL ISSUES We have touched on two of developmental psychology’s pervasive issues: continuity and discrete stages, and stability and change in personality. Although the stage theories of Piaget, Kohlberg, and Erikson have been modified in light of later research, each theory usefully alerts us to differences among people of different ages and helps us keep the lifespan perspective in view. Research findings that reveal how people’s traits continue to change in later life have helped create a new emphasis on lifelong development. Nevertheless, there is also an underlying consistency to most people’s temperaments and personality traits. SENSING THE WORLD: SOME BASIC PRINCIPLES To study sensation is to study an ageless question: How does the world out there get represented in here, inside our heads? Put another way, how are the external stimuli that strike our bodies transformed into messages that our brains comprehend? Thresholds Each species comes equipped with sensitivities that enable it to survive and thrive. We sense only a portion of the sea of energy that surrounds us, but to this portion we are exquisitely sensitive. Our absolute threshold for any stimulus is the minimum stimulation necessary for us to detect it 50 percent of the time. Signal detection researchers report that our individual absolute thresholds vary with our psychological state. Experiments reveal that we can process some information from stimuli too weak to recognize. But the restricted conditions under which this occurs would not enable unscrupulous opportunists to exploit us with subliminal messages. To survive and thrive, an organism must have difference thresholds low enough to detect minute changes in important stimuli. In humans, a difference threshold (also called a just noticeable difference, or jnd) increases in proportion to the size of the stimulus—a principle known as Weber’s law. Sensory Adaptation The phenomenon of sensory adaptation focuses our attention on informative changes in stimulation by diminishing our sensitivity to constant or routine odors, sounds, and touches. VISION Each sense receives stimulation, transduces it into neural signals, and sends these neural messages to the brain. We have glimpsed how this happens with vision. The Stimulus Input: Light Energy The energies we experience as visible light are a thin slice from the broad spectrum of electromagnetic radiation. The hue and brightness we perceive in a light depend on the wavelength and intensity. The Eye After entering the eye and being focused by a cameralike lens, light waves strike the retina. The retina’s light-sensitive rods and color-sensitive cones convert the light energy into neural impulses, which are coded by the retina before traveling along the optic nerve to the brain. Visual Information Processing In the cortex, individual neurons, called feature detectors, respond to specific features of a visual stimulus, and their information is pooled for interpretation by higher-level brain cells. Subdimensions of vision (color, movement, depth, and form) are processed separately and simultaneously, illustrating the brain’s capacity for parallel processing. The visual pathway faithfully represents retinal stimulation, but the brain’s representation incorporates our assumptions, interests, and expectations. Color Vision Research on how we see color supports two nineteenth-century theories. First, as the Young-Helmholtz trichromatic (three-color) theory suggests, the retina contains three types of cones. Each is most sensitive to the wavelengths of one of the three primary colors of light (red, green, or blue). Second, as opponent-process theory maintains, the nervous system codes the color-related information from the cones into pairs of opponent colors, as demonstrated by the phenomenon of afterimages and as confirmed by measuring opponent processes within visual neurons of the thalamus. The phenomenon of color constancy under varying illumination shows that our brains construct our experience of color. THE OTHER SENSES Hearing The Stimulus Input: Sound Waves The pressure waves we experience as sound vary in frequency and amplitude, and correspondingly in perceived pitch and loudness. The Ear Through a mechanical chain of events, sound waves traveling through the auditory canal cause minuscule vibrations in the eardrum. Transmitted via the bones of the middle ear to the fluid-filled cochlea, these vibrations create movement in tiny hair cells, triggering neural messages to the brain. Research on how we hear pitch supports both the place theory, which best explains the sensation of high-pitched sounds, and frequency theory, which best explains the sensation of low-pitched sounds. We localize sound by detecting minute differences in the intensity and timing of the sounds received by each ear. Hearing losses linked to conduction and nerve disorders can be caused by prolonged exposure to loud noise and by diseases and age-related disorders. Those who live with hearing loss face social challenges. Cochlear implants can enable some hearing by deaf children. But Deaf Culture advocates, noting that Sign is a complete language, question the enhancement. Touch and Pain Our sense of touch is actually four senses—pressure, warmth, cold, and pain—that combine to produce other sensations, such as "hot." One theory of pain is that a "gate" in the spinal cord either opens to permit pain signals traveling up small nerve fibers to reach the brain, or closes to prevent their passage. Because pain is both a physiological and a psychological phenomenon, it often can be controlled through a combination of physical and psychological treatments. Taste Taste, a chemical sense, is likewise a composite of five basic sensations—sweet, sour, salty, bitter, and umami—and of the aromas that interact with information from the taste buds. The influence of smell on our sense of taste is an example of sensory interaction. Smell Like taste, smell is a chemical sense, but there are no basic sensations for smell, as there are for touch and taste. Unlike the retina’s receptor cells that sense color by breaking it into component parts, the 5 million olfactory receptor cells with their 1000 different receptor proteins recognize individual odor molecules. Some odors trigger a combination of receptors. Like other stimuli, odors can spontaneously evoke memories and feelings. Body Position and Movement Finally, our effective functioning requires a kinesthetic sense, which notifies the brain of the position and movement of body parts, and a sense of equilibrium, which monitors the position and movement of the whole body PERCEPTUAL ORGANIZATION From a top-down perspective, we see how, aided by knowledge and expectations, we transform sensory information into meaningful perceptions. Visual and auditory illusions were fascinating scientists even as psychology emerged. Explaining illusions required an understanding of how we transform sensations into meaningful perceptions, so the study of perception became one of psychology’s first concerns. Conflict between visual and other sensory information is usually resolved with the mind’s accepting the visual data, a tendency known as visual capture. The early Gestalt psychologists were impressed with the seemingly innate way we organize fragmentary sensory data into whole perceptions. Our minds structure the information that comes to us in several demonstrable ways: Form Perception To recognize an object, we must first perceive it (see it as a figure) as distinct from its surroundings (the ground). We must also organize the figure into a meaningful form. Several Gestalt principles—proximity, similarity, continuity, closure, and connectedness—describe this process. Depth Perception Research on the visual cliff revealed that many species perceive the world in three dimensions at, or very soon after, birth. We transform two-dimensional retinal images into three-dimensional perceptions by using binocular cues, such as retinal disparity, and monocular cues, such as the relative sizes of objects. Perceptual Constancy Having perceived an object as a coherent figure and having located it in space, how then do we recognize it—despite the varying images that it may cast on our retinas? Size, shape, and lightness constancies describe how objects appear to have unchanging characteristics regardless of their distance, shape, or motion. These constancies explain several of the well-known visual illusions. For example, familiarity with the size-distance relationships in a carpentered world of rectangular shapes makes people more susceptible to the Müller-Lyer illusion. PERCEPTUAL INTERPRETATION The most direct tests of the nature-nurture issue come from experiments that modify human perceptions. Sensory Deprivation and Restored Vision For many species, infancy is a critical period during which experience must activate the brain’s innate visual mechanisms. If cataract removal restores eyesight to adults who were blind from birth, they remain unable to perceive the world normally. Generally, they can distinguish figure from ground and can perceive colors, but they are unable to recognize shapes and forms. In controlled experiments, animals have been reared with severely restricted visual input. When their visual exposure is returned to normal, they, too, suffer enduring visual handicaps. Perceptual Adaptation Human vision is remarkably adaptable. Given glasses that shift the world slightly to the left or right, or even turn it upside down, people manage to adapt their movements and, with practice, to move about with ease. Perceptual Set Clear evidence that perception is influenced by our experience—our learned assumptions and beliefs—as well as by sensory input comes from the many demonstrations of perceptual set and context effects. The schemas we have learned help us to interpret otherwise ambiguous stimuli, a fact that helps explain why some of us "see" monsters, faces, and UFOs that others do not. Thinking Critically About Extrasensory Perception Many believe in or claim to experience extrasensory perception (ESP). Parapsychologists have tried to document several forms of ESP—telepathy, clairvoyance, and precognition—but for several reasons, especially the lack of a reproducible ESP effect, most research psychologists remain skeptical. New studies using the ganzfeld procedure raised hopes of a measurable telepathy phenomenon, but overall, follow-up studies have not supported the phenomenon’s reliability. WAKING CONSCIOUSNESS Consciousness occurs in varied states. We have not only the normal states of seeing and hearing, reasoning and remembering, daydreams and fantasies, but also the altered consciousness of sleep, hypnotic states, chemically induced hallucinations, and near-death visions. Selective Attention At any moment we are conscious of a very limited amount of all that we are capable of experiencing. One example of this selective attention is the cocktail party effect—attending to only one voice among many. Levels of Information Processing Psychology began as the study of consciousness, then turned to the study of observable behavior. Today, scientific investigation of states of mind is again one of psychology’s pursuits. Speedy parallel processing handles subconscious information; conscious processing is serial and much slower. SLEEP AND DREAMS Biological Rhythms and Sleep Our age-old biological rhythms affect our daily functioning and especially our sleep and dreams. Our daily schedule of waking and sleeping is timed by a body clock known as circadian rhythm. Each night’s sleep also has a rhythm of its own, running from transitional Stage 1 sleep to deep Stage 4 sleep and back up to the more internally active REM sleep stage. This cycle repeats several times during a normal night’s sleep, with periods of Stage 4 sleep progressively shortening and of dream-laden REM sleep lengthening. Why Do We Sleep? Depriving people of sleep has not conclusively revealed why, physiologically, we need sleep. Recent research reveals that sleep is linked with the release of pituitary growth hormone and that it may help to restore brain tissues and consolidate memories. Sleep may also have played a protective role in human evolution. Sleep Disorders The disorders of sleep include insomnia (recurring wakefulness), narcolepsy (sudden uncontrollable sleepiness or lapsing into REM sleep), and sleep apnea (the stopping of breathing while asleep). Dreams Although conscious thoughts can occur during any sleep stage, awakening people during REM sleep yields predictable "dreamlike" reports; awakening during other sleep stages yields only an occasional fleeting image. Our dreams are mostly of ordinary events and everyday experiences; they tend to involve some anxiety or misfortune more than an achievement. Freud believed that a dream’s manifest content, or story line, is a censored version of its latent content, some underlying meaning that gratifies our unconscious wishes. More recent explanations of why we dream suggest that dreams (1) help process information from the day and fix it in memory, (2) serve a physiological function, and/or (3) are the brain’s efforts to synthesize periodic hallucinations (from activity bursts in the visual cortex) into a story line. Despite their differences, most theorists agree that REM sleep and its associated dreams serve an important function, as shown by the REM rebound that occurs following REM deprivation. HYPNOSIS Facts and Falsehoods Although hypnosis was historically linked with quackery, it has more recently become the subject of serious research. Psychologists now agree that hypnosis is a state of heightened suggestibility to which people are subject in varying degrees, and that, although hypnotic procedures may help someone to recall past events, the hypnotist’s beliefs frequently work their way into the subject’s recollections. They also agree that hypnotized people can no more be made to act against their will than can unhypnotized people. Hypnosis can be at least temporarily therapeutic, and hypnotizable people can enjoy significant pain relief. Explaining the Hypnotized State Hypnosis is at least partly a by-product of normal social and cognitive processes. Many researchers believe it also is an altered state of consciousness, perhaps involving a dissociation between levels of consciousness. DRUGS AND CONSCIOUSNESS Psychoactive drugs, including depressants, stimulants, and hallucinogens, also alter consciousness. Dependence and Addiction Drugs often trigger withdrawal symptoms—negative aftereffects that oppose and offset their temporary pleasure. Such symptoms can lead to physical or psychological dependence. Medical use of drugs rarely creates addictions, however, and many who do suffer drug addictions overcome them when their social context changes. Psychoactive Drugs Alcohol, barbiturates, and the opiates act by depressing neural functioning. Each offers pleasures, but at the cost of impaired memory and self-awareness or other physical consequences. Caffeine, nicotine, the amphetamines, cocaine, and Ecstasy act by stimulating neural functioning. As with nearly all psychoactive drugs, they act at the synapses by influencing the brain’s neurotransmitters, and their effects depend on dosage and the user’s personality and expectations. LSD and marijuana can distort the user’s judgments of time and, depending on the setting, can alter sensations and perceptions. Influences on Drug Use Drug use among teenagers and young adults declined during the 1980s, as attitudes changed, and began a rebound during the mid-1990s. Psychological factors (such as stress, depression, and hopelessness) and social factors (such as peer pressure) combine to lead many people to experiment with—and become dependent on—drugs. Some people also appear to have a greater biological susceptibility to dependence on drugs such as alcohol. CLASSICAL CONDITIONING Although learning by association had been discussed for centuries, it remained for Ivan Pavlov to capture the phenomenon in his classic experiments on conditioning. Pavlov’s Experiments Pavlov repeatedly presented a neutral stimulus (such as a tone) just before an unconditioned stimulus (UCS, food) that triggered an unconditioned response (UCR, salivation). After several repetitions, the tone alone (now the conditioned stimulus, CS) began triggering a conditioned response (CR, salivation). Further experiments on acquisition revealed that classical conditioning was usually greatest when the CS was presented just before the UCS, thus preparing the organism for what was coming. Other experiments explored the phenomena of extinction, spontaneous recovery, generalization, and discrimination. Pavlov’s work laid a foundation for John B. Watson’s emerging belief that psychology, to be an objective science, should study only overt behavior, without considering unobservable mental activity. Watson called this position behaviorism. Updating Pavlov’s Understanding The behaviorists’ optimism that learning principles would generalize from one response to another and from one species to another has been tempered. Conditioning principles, we now know, are cognitively influenced and biologically constrained. In classical conditioning, animals learn when to "expect" an unconditioned stimulus. Moreover, animals are biologically predisposed to learn associations between, say, a peculiar taste and a drink that will make them sick, which they will then avoid. They don’t, however, learn to avoid a sickening drink announced by a noise. Pavlov’s Legacy Pavlov taught us that principles of learning apply across species, that significant psychological phenomena can be studied objectively, and that conditioning principles have important practical applications. OPERANT CONDITIONING Through operant conditioning, organisms learn to produce behaviors that are followed by reinforcing stimuli and to suppress behaviors that are followed by punishing stimuli. Skinner’s Experiments Skinner showed that when placed in an operant chamber, rats or pigeons can be shaped to display successively closer approximations of a desired behavior. Researchers have also studied the effects of primary and secondary reinforcers, and of immediate and delayed reinforcers. Partial reinforcement schedules (fixed-ratio, variable-ratio, fixed-interval, and variable-interval) produce slower acquisition of the target behavior than does continuous reinforcement, but they also create more resistance to extinction. Punishment is most effective when it is strong, immediate, and consistent. However, it can have undesirable side effects. Updating Skinner’s Understanding Skinner’s emphasis on external control of behavior made him both influential and controversial. Many psychologists criticized Skinner (as they did Pavlov) for underestimating the importance of cognitive and biological constraints. For example, research on latent learning and overjustification further indicates the importance of cognition in learning. Skinner’s Legacy Skinner stimulated vigorous intellectual debate on the nature of human freedom and the strategies and ethics of managing people. Nevertheless, his operant principles are being applied in schools, the workplace, and homes. For example, computer-assisted instruction both shapes and reinforces learning. Immediate reinforcement boosts worker productivity. And individuals can strengthen their own desired behavior and extinguish unwanted behavior. LEARNING BY OBSERVATION Another important type of learning, especially among humans, is what Albert Bandura and others call observational learning. In experiments, children tend to imitate what a model both does and says, whether the behavior is social or antisocial. Such experiments have stimulated research on social modeling in the home, within peer groups, and in the media. Children are especially likely to imitate those they perceive to be like them, successful, or admirable. THE PHENOMENON OF MEMORY Information Processing Memory is the persistence of learning over time. Psychologists have proposed several information-processing models of memory. We will use the influential three-stage processing model, which suggests that we (1) register fleeting sensory memories, some of which are (2) processed into on-screen short-term or working memories, a tiny fraction of which are (3) encoded for long-term memory and, possibly, later retrieval. ENCODING: GETTING INFORMATION IN How We Encode and What We Encode Some types of information, notably information concerning space, time, and frequency, we encode mostly automatically. Other types of information, including much of our processing of meaning, imagery, and organization, require effort. Mnemonic devices depend on the memorability of visual images and of information that is organized into chunks. Organizing information into chunks and hierarchies also aids memory. STORAGE: RETAINING INFORMATION Sensory Memory Information first enters the memory system through the senses. We register and briefly store visual images via iconic memory and sounds via echoic memory. Short-Term and Long-Term Memory Our short-term memory span for information just presented is limited—a seconds-long retention of up to about seven items, depending on the information and how it is presented. Our capacity for storing information permanently in long-term memory is essentially unlimited. Storing Memories in the Brain The search for the physical basis of memory has recently focused on the synapses and their neurotransmitters; on the long-term potentiation of brain circuits, such as those running through the hippocampus; and on the effects of stress hormones on memory. Studies of people with brain damage reveal that we have two types of memory—explicit (declarative) memories processed by the hippocampus, and implicit (nondeclarative) memories processed by the cerebellum and the amygdala. RETRIEVAL: GETTING INFORMATION OUT Retrieval Cues To be remembered, information that is "in there" must be retrieved, with the aid of associations (cues) that prime the memory. Cues sometimes come from returning to the original context. Mood affects memory, too. While in a good or bad mood, we tend to retrieve memories congruent with that mood. FORGETTING One explanation of forgetting is that we fail to encode information for entry into our memory system. Without effortful processing, we never notice or process much of what we sense. Memories may also fade after storage—often rapidly at first, and then leveling off. Forgetting also results from retrieval failure. Retrieval-related forgetting may be caused by a lack of retrieval cues, by proactive or retroactive interference, or even, said Freud, by motivated forgetting. MEMORY CONSTRUCTION Memories are not stored as exact copies, and they certainly are not retrieved as such. Rather, we construct our memories, using both stored and new information. Thus, when child or adult eyewitnesses are subtly exposed to misinformation after an event, they often believe they saw the misleading details as part of the event. People also exhibit source amnesia, by attributing something heard, read, or imagined to a wrong source. Because false memories feel like true memories and are equally durable, sincerity need not signify reality. Memory researchers are especially suspicious of claims of long-repressed memories of sexual abuse, UFO abduction, or other traumas "recovered" with the aid of a therapist or suggestive book. More than we once supposed, incest and abuse happen. But unless the victim was a child too young to remember any early experiences, such traumas are usually remembered vividly, not banished into an active but inaccessible unconscious. IMPROVING MEMORY The psychology of memory suggests concrete strategies for improving memory. These include spaced study; active rehearsal; encoding of well-organized, vivid, meaningful associations; mnemonic techniques; returning to contexts and moods that are rich with associations; recording memories before misinformation can corrupt them; minimizing interference; and self-testing and rehearsal. THINKING Our cognitive system receives, perceives, and retrieves information, which we then use to think and communicate, sometimes wisely, sometimes foolishly. This chapter has so far explored how we form concepts, solve problems, and make judgments and decisions. Concepts Concepts simplify and order the world by organizing it into a hierarchy of categories. Concepts often form around prototypes, or best examples of a category. Matching objects and ideas with prototypes is an efficient way of making snap judgments about what belongs in a specific category. Solving Problems When faced with a novel situation for which no well-learned response will do, we may use such strategies as algorithms and heuristics. Sometimes the solution comes in a flash of insight. We do, however, face obstacles to successful problem solving. The confirmation bias predisposes us to verify rather than challenge our hypotheses. And fixations, such as mental set and functional fixedness, may prevent our taking a needed fresh perspective on a problem. Making Decisions and Forming Judgments Our use of heuristics, such as representativeness and availability, provides highly efficient but occasionally misleading guides for making quick decisions and forming intuitive judgments. Our tendencies to seek confirmation of our hypotheses and to use quick and easy heuristics can blind us to our vulnerability to error, a phenomenon known as overconfidence. And the way someone poses, or frames, a question affects our responses. We tend to show a belief bias in our reasoning, accepting as more logical those conclusions that agree with our beliefs. We also exhibit belief perseverance, clinging to our ideas because the explanation we accepted as valid lingers in the mind even after the basis for the ideas has been discredited. Yet despite our capacity for error and our susceptibility to bias, human cognition is remarkably efficient and adaptive. As we gain expertise in a field, we grow adept at making quick, shrewd judgments. LANGUAGE Language Development Among the marvels of nature is a child’s ability to acquire language. The ease with which children progress from the babbling stage through the one-word stage to the telegraphic speech of the two-word stage and beyond has sparked a lively debate concerning how they do it. Behaviorist B. F. Skinner proposed that we learn language by the familiar principles of association, reinforcement, and imitation. Challenging this claim, linguist Noam Chomsky argued that children are biologically prepared to learn words and use grammar. Cognitive neuroscientists emphasize that for mastery of grammar, the learning that occurs during life’s first few years, when the brain is building a dense network of neuronal connections, is critical. Thinking and Language We consider thinking and language in the same chapter, for they are hard to separate. Language Influences Thinking Words convey ideas, and different languages embody different ways of thinking. Although the linguistic relativity hypothesis suggested that language determines thought, it is more accurate to say that language influences thought. Studies of the effects of the generic pronoun he and the ability of vocabulary enrichment to enhance thinking reveal the influence of words. Thinking in Images We sometimes think in images rather than in words, and we invent new words or new combinations of old words to describe new ideas. So we might say that our thinking affects our language, which then affects our thought. Animal Thinking and Language Evidence accumulates that primates at some level count, display insight, create tools, and transmit cultural innovations. Another vigorously debated issue is whether language is uniquely human. Animals obviously communicate. Bees, for example, communicate the location of food through an intricate combination of dance and sound. And several teams of psychologists have taught various species of apes, including a number of chimpanzees, to communicate with humans by signing or by pushing buttons wired to a computer. Apes have developed considerable vocabularies. They string words together to express meaning and to make and follow requests. Skeptics point out important differences between apes’ and humans’ facilities with language, especially in their respective abilities to order words using proper syntax. Nevertheless, these studies reveal that apes have considerable cognitive ability. INTELLIGENCE The Origins of Intelligence Testing Among the most controversial issues in psychology is the debate over intelligence testing: whether tests can measure and quantify a person’s abilities and how widely the results can be used fairly. More than a century ago in France, Alfred Binet started the modern intelligence-testing movement by developing questions that helped predict children’s future progress in the Paris school system. Lewis Terman of Stanford University revised Binet’s work for use in the United States. Terman believed his Stanford-Binet could help guide people toward appropriate opportunities, but more than Binet, he believed that intelligence was inherited. During the early part of the twentieth century, intelligence tests were sometimes used in ways that, in hindsight, even their designers regretted—to "document" a presumed innate inferiority of certain ethnic and immigrant groups. What Is Intelligence? It is misleading to reify concepts such as "intelligence" and "giftedness"—to regard these abstract concepts as if they were real, concrete things. To most psychologists, intelligence is defined as the ability to learn from experience, solve problems, and adapt to new situations. One General Ability or Several Specific Abilities? Psychologists agree that people have specific abilities, such as verbal and mathematical aptitudes. However, they debate whether a general intelligence (g) factor runs through them all. Factor analysis and studies of special conditions, such as the savant syndrome, have identified clusters of mental aptitudes. Emotional Intelligence Psychologists have recently described emotional intelligence as the ability to perceive, understand, and regulate emotions. Emotionally intelligent individuals are especially self-aware, and their empathy enables them to read others’ emotions. Creativity and Intelligence Intelligence correlates weakly with creativity. Increases in intelligence beyond a necessary threshold level are not linked with increased creativity. Assessing Intelligence Tests are commonly classified as either aptitude tests (designed to predict learning ability, as is the Wechsler) or achievement tests (designed to assess current competence). Principles of Test Construction A good test must be standardized, so that any person’s performance can be meaningfully compared to others’; reliable, so it yields dependably consistent scores; and valid, so it measures what it is supposed to measure. Test scores usually fall into a bell-shaped distribution, the normal curve. The average score is assigned an arbitrary number (such as 100 on an intelligence test). Aptitude tests tend to be highly reliable, but they are weak predictors of success in life. However, their predictive validity for academic success in the early grades is fairly strong. Test validity weakens for predicting grades in college and even more so in graduate school, as the range of student abilities becomes more restricted. Genetic and Environmental Influences on Intelligence Because of its political and racial overtones, the debate over the nature and nurture of intelligence is an ongoing controversy. Genetic Influences Studies of twins, family members, and adopted children together point to a significant hereditary contribution to intelligence scores. Heritability, the proportion of person-to-person variation attributable to genes, can vary, depending on the range of populations and environments studied. Environmental Influences These same studies, plus others that compare children reared in extremely impoverished or enriched environments or in different cultures, indicate that life experiences also significantly influence intelligence test performance. Group Differences in Intelligence Test Scores Like individuals, groups vary in intelligence test scores. Hereditary variation within a group need not signify a hereditary explanation of between-group differences. In the case of the racial gaps in test scores, the evidence suggests that environmental differences are largely, perhaps entirely, responsible. Psychologists debate evolutionary and cultural explanations of gender differences in specific aptitudes. The Question of Bias Aptitude tests aim to predict how well a test-taker will perform in a given situation. So they are necessarily "biased" in the sense that they are sensitive to performance differences caused by cultural experience. But bias can also mean what psychologists commonly mean by the term—that a biased test predicts less accurately for one group than for another. In this sense of the term, most experts do not consider the major aptitude tests to be significantly biased. MOTIVATIONAL CONCEPTS Motivation is the energizing and directing of behavior, the force behind our yearning for food, our longing for sexual intimacy, our need to belong, and our desire to achieve. Instincts and Evolutionary Psychology Under Darwin’s influence, early theorists viewed behavior as controlled by biological forces, such as specific instincts. When it became clear that people were naming, not explaining, various behaviors by calling them instincts, this approach fell into disfavor. The underlying idea—that genes predispose species-typical behavior—is, however, still influential in evolutionary psychology. Drives and Incentives Most physiological needs create aroused psychological states that drive us to reduce or satisfy those needs. The aim of drive reduction is internal stability, or homeostasis. Thus, drive reduction motivates survival behaviors, such as eating and drinking. Not only are we pushed by our internal drives, we are also pulled by external incentives. Depending on our personal experiences, some stimuli (for example, certain foods) will arouse our desires. Optimum Arousal Rather than reducing a physiological need or tension state, some motivated behaviors increase arousal. Curiosity-driven behaviors, for example, suggest that too little as well as too much stimulation can motivate people to seek an optimum level of arousal. A Hierarchy of Motives Maslow’s hierarchy of needs expresses the idea that, until satisfied, some motives are more compelling than others. HUNGER The Physiology of Hunger Hunger’s inner push primarily originates not from the stomach’s contractions but from variations in body chemistry, including hormones that heighten or reduce hunger. For example, we are likely to feel hungry when our glucose levels are low or when ghrelin is secreted by an empty stomach. This information is integrated by the hypothalamus, which regulates the body’s weight as it influences our feelings of hunger and satiety. To maintain weight, the body also adjusts its metabolic rate of energy expenditure. The Psychology of Hunger Our preferences for certain tastes are partly genetic and universal, but also partly learned in a cultural context. The impact of psychological factors, such as challenging family settings and weight-obsessed societal pressures, on eating behavior is dramatic in people with anorexia nervosa, who keep themselves on near-starvation rations, and in those with bulimia nervosa, who binge and purge in secret. In the past half-century a dramatic increase in poor body image has coincided with a rise in eating disorders among women in Western cultures. In addition to cultural pressures, low self-esteem and negative emotions (with a possible genetic component) seem to interact with stressful life experiences to produce anorexia and bulimia. SEXUAL MOTIVATION Describing Sexual Behavior Although early data-collection efforts by Alfred Kinsey and others have been criticized for their methodology, information about human sexual practices continues to accumulate. We do know that sexual behaviors vary across both place and time and that the range of "normal" sexual interests and behaviors is very broad. The Physiology of Sex Physiologically, the human sexual response cycle normally follows a pattern of excitement, plateau, orgasm, and resolution, followed in males by a refractory period, during which renewed arousal and orgasm are impossible. Sex hormones, in combination with the hypothalamus, help our bodies develop and function as either male or female. In nonhuman animals, hormones also help stimulate sexual activity. In humans, they influence sexual behavior more loosely, especially once sufficient hormone levels are present. The Psychology of Sex External stimuli can trigger sexual arousal in both men and women. Sexually explicit materials may also lead people to perceive their partners as comparatively less appealing and to devalue their relationships. In combination with the internal hormonal push and the external pull of sexual stimuli, fantasies (imagined stimuli) influence sexual arousal. Sexual disorders, such as premature ejaculation and female orgasmic disorder, are being successfully treated by new methods, which assume that people learn and can modify their sexual responses. Adolescent Sexuality Adolescents’ physical maturation fosters a sexual dimension to their emerging identity. But culture is a big influence, too, as is apparent from varying rates of teen intercourse and pregnancy. A near-epidemic of sexually transmitted infections has triggered new research and educational programs pertinent to adolescent sexuality. Sexual Orientation One’s heterosexual or homosexual orientation seems neither willfully chosen nor willfully changed. Preliminary new evidence links sexual orientation with genetic influences, prenatal hormones, and certain brain structures. The increasing public perception that sexual orientation is biologically influenced is associated with increasing acceptance of gays and lesbians and their relationships. Sex and Human Values Sex research and education are not value-free. Some say that sex-related values should therefore be openly acknowledged, recognizing the emotional significance of sexual expression. Human sexuality at its life-uniting and loverenewing best affirms our deep need to belong. THE NEED TO BELONG No one is an island; we are all, as John Donne noted in 1624, part of the human continent. Our need to affiliate—to feel connected and identified with others—boosted our ancestors’ chances for survival and is therefore part of our human nature. We experience our need to belong when suffering the breaking of social bonds, when feeling the gloom of loneliness or the joy of love, and when seeking social acceptance. ACHIEVEMENT MOTIVATION Identifying Achievement Motivation Some human behaviors are energized and directed without satisfying any apparent biological need. Achieving personal goals, for example, may be motivated by a person’s social needs for competence and independence. People with a high need to achieve tend to prefer moderately challenging tasks and tend to persist in accomplishing them. Sources of Achievement Motivation To understand why people with similar abilities often differ widely in their achievements, psychologists have studied highly motivated children. Many achievement-motivated children have parents and teachers who encourage and affirm independent achievement. Such children may learn to associate achievement with positive emotions and to attribute their success to their own competence. THEORIES OF EMOTION The James-Lange and Cannon-Bard Theories One of the oldest theoretical controversies regarding emotion focuses on the timing of our feelings in relation to the physiological responses that accompany emotion. William James and Carl Lange proposed that we feel emotion after we notice our physiological responses. Walter Cannon and Philip Bard believed that we feel emotion at the same time that our bodies respond. Most researchers today agree with Cannon and Bard but also note that, as James and Lange pointed out, physical reactions are an important ingredient of emotion. Cognition and Emotion A more recent controversy among emotion researchers concerns whether we can experience human emotions apart from cognition. Can we feel before we think? Stanley Schachter’s two-factor theory of emotion contends that the cognitive labels we put on our states of arousal are an essential ingredient of emotion. Richard Lazarus agrees that cognition is essential: Many important emotions arise from our interpretations or inferences. Robert Zajonc and Joseph LeDoux, however, believe that some simple emotional responses occur instantly, not only outside of conscious awareness but before any cognitive processing occurs. The issue has practical implications: To the degree that emotions are rooted in thinking, we can hope to change them by changing our thinking. EMBODIED EMOTION Emotion and Physiology Emotions are both psychological and physiological. Much of the physiological activity is controlled by the autonomic nervous system’s sympathetic (arousing) and parasympathetic (calming) divisions. Our performance on a task is usually best when arousal is moderate, though this varies with the difficulty of the task. The Physiology of Specific Emotions When two emotions are similarly arousing and negative (or positive) the physiological responses that accompany them are nearly indistinguishable to an untrained observer. However, scientists have discovered subtle differences in activity in the brain’s cortical areas, in use of brain pathways, and in secretion of hormones associated with different emotions. Polygraphs measure several physiological indicators of emotion. Although they detect lies at a rate better than chance, they are not accurate enough to justify their widespread use in business and government. The use of guilty knowledge questions may increase the accuracy of these tests. EXPRESSED EMOTION Nonverbal Communication Much of our communication is through the body’s silent language. Psychologists have studied people’s abilities to detect emotion, even from thin slices of behavior. High-tech equipment has enabled researchers to make more precise linkages between some emotions and facial muscles. Culture and Emotional Expression Although some gestures are culturally determined, facial expressions, such as those of happiness and fear, are common the world over. In communal cultures that value interdependence, intense displays of potentially disruptive emotions are infrequent. The Effects of Facial Expressions Expressions do more than communicate emotion. They also amplify the felt emotion and signal the body to respond accordingly. Emotions, then, arise from the interplay of cognition, physiology, and expressive behaviors. EXPERIENCED EMOTION Among various human emotions, we looked closely at how we experience two: anger and happiness. Anger Anger is most often evoked by events that not only are frustrating or insulting but also are interpreted as willful, unjustified, and avoidable. Blowing off steam may be temporarily calming, but in the long run it does not reduce anger. Expressing anger can actually make us angrier. Happiness A good mood boosts people’s perceptions of the world and their willingness to help others. The moods triggered by the day’s good or bad events seldom last beyond that day. Even significant good events, such as a substantial rise in income, seldom increase happiness for long. We can explain the relativity of happiness with the adaptation-level phenomenon and the relative deprivation principle. Nevertheless, some people are usually happier than others, and researchers have identified factors that predict such happiness. STRESS AND HEALTH People’s behaviors and stress responses are major influences on health and disease. Health psychology is contributing to the interdisciplinary field of behavioral medicine, which provides new avenues for the prevention and treatment of illness. Among health psychology’s concerns are the effects of stress and the promotion of healthier living. Stress and Stressors Walter Cannon viewed stress, the process by which we appraise and respond to events that challenge or threaten us, as a "fight-or-flight" system. Hans Selye saw it as a three-stage (alarm-resistance-exhaustion) general adaptation syndrome. Modern research on stress assesses the health consequences of catastrophic events, significant life changes, and daily hassles. The events that tend to provoke stress responses are those that we perceive as both negative and uncontrollable. Stress and the Heart Coronary heart disease, the number one cause of death, has been linked with the competitive, hard-driving, impatient, and (especially) anger-prone Type A personality. Under stress, the body of a reactive, hostile person secretes more of the hormones that accelerate the buildup of plaque on the heart’s artery walls. Stress and Susceptibility to Disease Stress diverts energy from the immune system, making a person more vulnerable to infections and malignancy. Although stress does not cause diseases such as cancer, it may influence the disease’s progression. Research indicates that conditioning also influences the immune system’s responses. PROMOTING HEALTH Preventing illness and promoting health through stress management and behavior change is far easier and more costeffective than attempting to treat problems after they occur. Coping with Stress Among the components of stress-management programs are training in aerobic exercise, biofeedback, and relaxation. Although the degree of mind control over the body that can be gained through biofeedback has fallen short of early expectations, it sometimes helps control tension headaches and high blood pressure. Simple relaxation exercises offer some of the same benefits. Counseling Type A heart-attack survivors to slow down and relax has helped lower rates of recurring attacks. Social support also helps people cope, partly by buffering the impact of stress. Researchers are now trying to understand the active components of the religion-health correlation. HISTORIC PERSPECTIVES ON PERSONALITY The Psychoanalytic Perspective Exploring the Unconscious Sigmund Freud’s treatment of emotional disorders led him to believe that they sprang from unconscious dynamics, which he sought to analyze through free associations and dreams. Freud saw personality as composed of pleasure-seeking psychic impulses (the id), a reality-oriented executive (the ego), and an internalized set of ideals (the superego). Freud believed that children develop through psychosexual stages—the oral, anal, phallic, latency, and genital stages. He suggested that our personalities are influenced by how we have resolved conflicts associated with these stages and whether we have remained fixated at any stage. Tensions between demands of the id and superego cause anxiety. The ego copes by using defense mechanisms, of which repression is the most basic. Assessing the Unconscious Projective tests are tests that attempt to assess personality by presenting ambiguous stimuli that are designed to reveal the unconscious. Although projective tests, such as the Rorschach inkblots, have questionable reliability or validity, some clinicians continue to use them. Evaluating the Psychoanalytic Perspective Neo-Freudians Alfred Adler and Karen Horney accepted many of Freud’s ideas, as did Carl Jung. But they also argued that we have motives other than sex and aggression, and that the ego’s conscious control is greater than Freud supposed. Today’s research psychologists find some of Freud’s specific ideas implausible, unvalidated, or contradicted by new research, and they note that his theory offers only after-the-fact explanations. Many researchers now believe that repression rarely, if ever, occurs. Nevertheless, Freud drew psychology’s attention to the unconscious, to the struggle to cope with anxiety and sexuality, and to the conflict between biological impulses and social restraints. His cultural impact has been enormous. The Humanistic Perspective Humanistic psychologists have sought to turn psychology’s attention from baser motives and environmental conditioning to the growth potential of healthy people, as seen through the individual’s own experiences. Abraham Maslow’s Self-Actualizing Person Abraham Maslow believed that if basic human needs are fulfilled, people will strive to actualize their highest potential. To describe self-actualization, he studied some exemplary personalities and summarized his impressions of their qualities. Carl Rogers’ Person-Centered Perspective To nurture growth in others, Carl Rogers advised being genuine, accepting, and empathic. In such a climate, people can develop a deeper self-awareness and a more realistic and positive self-concept. Assessing the Self Humanistic psychologists assessed personality through questionnaires on which people report their self-concept and in therapy by seeking to understand others’ subjective personal experiences. Evaluating the Humanistic Perspective Humanistic psychology helped to renew psychology’s interest in the self. Nevertheless, humanistic psychology’s critics complain that its concepts are vague and subjective, its values individualist and self-centered, and its assumptions naively optimistic. CONTEMPORARY RESEARCH ON PERSONALITY The Trait Perspective Exploring Traits Rather than explain the hidden aspects of personality, trait researchers describe the predispositions that underlie our actions. For example, through factor analysis, researchers have isolated important dimensions of personality. Assessing Traits Personality inventories (like the MMPI-2) are questionnaires on which people respond to items designed to gauge a wide range of feelings and behaviors. Items on the tests are empirically derived, and the tests are objectively scored. Peer reports may, however, provide more trustworthy clues to a person’s behavioral traits. The Big Five Factors Five personality dimensions—stability, extraversion, openness, agreeableness, and conscientiousness—offer a reasonably comprehensive picture of personality. Genetic predispositions and other biological factors influence these traits. Evaluating the Trait Perspective Critics of the trait perspective question the consistency with which traits are expressed. Although people’s traits persist over time, human behavior varies widely from situation to situation. Despite these variations, a person’s average behavior across different situations tends to be fairly consistent. Traits matter. The Social-Cognitive Perspective The social-cognitive perspective applies principles of learning, cognition, and social behavior to personality, with particular emphasis on the ways in which our personality influences and is influenced by our interaction with the environment. It assumes reciprocal determinism—that personal-cognitive factors combine with the environment to influence people’s behavior. By studying how people vary in their perceived locus of control and in their experiences of learned helplessness, researchers have found that a sense of personal control helps people to cope with life. Research on learned helplessness has evolved into research on optimism and now into a broader positive psychology movement. Assessing Behavior in Situations Social-cognitive researchers observe how people’s behaviors and beliefs both affect and are affected by their situations. They have found that the best way to predict someone’s behavior in a given situation is to observe that person’s behavior pattern in similar situations. Evaluating the Social-Cognitive Perspective Although faulted for slighting the importance of unconscious dynamics, emotions, and inner traits, the social-cognitive perspective builds on psychology’s well-established concepts of learning and cognition and reminds us of the power of social situations. Exploring the Self Research on the self has recently expanded to include the concept of possible selves, the visions of ourselves we dream of becoming, and the concept of the spotlight effect, the assumption that we overestimate others noticing and evaluating our appearance, performance, and blunders. But research confirms the importance of high self-esteem and the potency of the self-serving bias. Culture and the Self Individuals and cultures vary in giving priority to "me" or "we"—to personal control and individual achievement or to social connections and solidarity. Self-reliant individualism defines identity in terms of personal goals and attributes; socially connected collectivism gives priority to group goals and to one’s social identity and commitments. The Modern Unconscious Mind Freud’s view of the unconscious—a reservoir of repressed and mostly unacceptable thoughts, wishes, feelings, and memories—has not survived empirical scrutiny. But current information-processing research confirms that our access to all that goes on in our mind is very limited. The current view of the unconscious is that it consists of schemas that control our perceptions; priming that points us toward certain interpretations; parallel processing (as in vision) that occurs without our conscious knowledge; implicit memories of learned skills; instantly activated emotions; and self-concepts and stereotypes that filter information about ourselves and others. Freud’s idea that we defend ourselves against anxiety also has a contemporary version, but again in a much altered form. The terror-management theory proposes that our awareness of our own vulnerability and inevitable death is a source of anxiety by affirming our worldviews, acting to enhance our self-esteem, and cleaving to close others. Psychology’s false consensus effect (the tendency to overestimate the effect to which others share our beliefs and behaviors) bears a resemblance to Freud’s projection defense mechanism. Reaction formation also seems to happen. But current theorists believe that the motivation triggering defense mechanisms is a need to protect our self-image, not a well of instinctual energy or impulses. PERSPECTIVES ON PSYCHOLOGICAL DISORDERS Psychological disorders fascinate us, partly because most of us will at some time experience or witness them close at hand. Defining Psychological Disorders Between normality and abnormality there is not a gulf but a somewhat arbitrary line. Where we draw this line depends on how atypical, disturbing, maladaptive, and unjustifiable a person’s behavior is. Understanding Psychological Disorders The medical model’s assumption that psychological disorders are mental illnesses displaced earlier views that demons and evil spirits were to blame. However, critics question the medical model’s labeling of psychological disorders as sicknesses. Most mental health workers today adapt a bio-psycho-social perspective. They assume that disorders are influenced by genetic predisposition, physiological states, psychological dynamics, and social circumstances. Classifying Psychological Disorders Many psychiatrists and psychologists use the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) for naming and describing psychological disorders in treatment and research. Diagnostic labels facilitate mental health professionals’ communications and research, and most health insurance policies in North America require DSM-IV diagnoses before they will pay for therapy. Labeling Psychological Disorders Critics point out the price we pay for these benefits of classifying disorders: Labels also can create preconceptions that unfairly stigmatize people and bias our perceptions of their past and present behavior. ANXIETY DISORDERS Anxiety is part of our everyday experience. It is classified as a psychological disorder only when it becomes distressing or persistent or is characterized by maladaptive behaviors intended to reduce it. Four Anxiety Disorders Those who suffer generalized anxiety disorder may for no clear reason feel persistently and uncontrollably tense and uneasy. Anxiety escalates into periodic episodes of intense dread for those suffering panic disorder. Those with a phobic disorder may be irrationally afraid of a specific object or situation. Persistent and repetitive thoughts and actions characterize obsessive-compulsive disorder. Explaining Anxiety Disorders The psychoanalytic perspective viewed anxiety disorders as the discharging of repressed impulses. Psychologists now tend to consider these disorders from the learning and biological perspectives. The learning perspective sees anxiety disorders as a product of fear conditioning, stimulus generalization, reinforcement, and observational learning. The biological perspective considers possible evolutionary, genetic, and physiological influences. DISSOCIATIVE AND PERSONALITY DISORDERS Dissociative Disorders Dissociative disorders occur when, under stress, a person’s conscious awareness becomes dissociated (separated) from previous memories, thoughts, and feelings. Most mysterious of all dissociative disorders are cases of dissociative identity (multiple personality). The afflicted person is said to have two or more distinct personalities, with the original typically unaware of the other(s). Skeptics question whether this disorder may be a cultural phenomenon, finding it suspicious that the disorder has just recently become popular and is virtually nonexistent outside North America. Personality Disorders Personality disorders are enduring, maladaptive patterns of behavior that impair social functioning. For society, the most troubling of these is the remorseless and fearless antisocial personality. MOOD DISORDERS Mood disorders are characterized by emotional extremes. The two principal forms are major depressive disorder and bipolar disorder. Major Depressive Disorder In major depression, the person—without apparent reason—descends for weeks or months into deep unhappiness, lethargy, and feelings of worthlessness before rebounding to normality. Although less disabling, dysthymic disorder is marked by chronic low energy and poor self-esteem. Bipolar Disorder In the less common bipolar disorder, the person alternates between the hopelessness and lethargy of depression and the hyperactive, wildly optimistic, impulsive phase of mania. Explaining Mood Disorders Current research on depression is vigorously exploring two sets of influences. The first focuses on genetic predispositions and neurotransmitter abnormalities. The second views the cycle of depression from a social-cognitive perspective, in light of cyclic self-defeating beliefs, learned helplessness, negative attributions, and aversive experiences. SCHIZOPHRENIA Schizophrenia typically strikes during late adolescence. It affects men and women about equally, and it seems to occur in all cultures. Symptoms of Schizophrenia Schizophrenia shows itself in disorganized thinking (nonsensical talk and delusions, which may stem from a breakdown of selective attention); disturbed perceptions (including hallucinations); and inappropriate emotions and actions. It is rarely a one-time episode. Subtypes of Schizophrenia Schizophrenia is a set of disorders that emerge either gradually from a chronic history of social inadequacy (in which case the outlook is dim) or suddenly in reaction to stress (in which case the prospects for recovery are brighter). Understanding Schizophrenia Multiple factors converge to create schizophrenia. As they have for depression, researchers have linked certain forms of schizophrenia with brain abnormalities, in this case, with enlarged, fluid-filled cerebral cavities or increased receptors for the neurotransmitter dopamine, known to be a major player in schizophrenia. Twin and adoption studies also point to a genetic predisposition that, in conjunction with environmental factors, may bring about a schizophrenia disorder. RATES OF PSYCHOLOGICAL DISORDERS A 1980s NIMH survey of nearly 20,000 institutionalized and community residents and a later government survey revealed that one in five U.S. adults was currently experiencing a psychological disorder. Among Americans who have ever experienced a psychological disorder, the three most common were phobic disorder; alcohol abuse or dependence (with men outnumbering women five to one); and mood disorder (with women outnumbering men two to one). THE PSYCHOLOGICAL THERAPIES Psychological therapy, or psychotherapy, is an emotionally charged, confiding interaction between a trained therapist and someone suffering from psychological difficulties. The major psychotherapies derive from the familiar psychoanalytic, humanistic, behavioral, and cognitive perspectives on psychology. Psychoanalysis Those influenced by the psychoanalytic perspective try to help people gain insight into the unconscious origins of their disorders and to work through the accompanying feelings. To do so, an analyst may draw on techniques such as free association and dream analysis, and interpret resistance and the transference to the therapist of long-repressed feelings. Traditional psychoanalysis, which is no longer practiced widely, is criticized for assuming repression, for after-the-fact interpretations, and for being time-consuming and costly. The more common psychodynamic therapy is influenced by the psychoanalytic perspective’s concern for providing insight into childhood experiences and defense mechanisms. But it offers a briefer treatment form and often incorporates other techniques into the therapy sessions. Humanistic Therapies Unlike psychoanalysts, humanistic therapists focus on clients’ current conscious feelings and on their taking responsibility for their own growth. Carl Rogers, in his client-centered therapy, used active listening to express genuineness, acceptance, and empathy. Behavior Therapies Behavior therapists do not attempt to explain the origin of problem behaviors or to promote self-awareness. Instead, they attempt to modify the problem behaviors themselves. Thus, they may countercondition behaviors through systematic desensitization or aversive conditioning. Or they may apply operant conditioning principles with behavior modification techniques, such as token economies. Cognitive Therapies The cognitive therapies, such as Aaron Beck’s cognitive therapy for depression, aim to change self-defeating thinking by training people to look at themselves in new, more positive ways. GROUP AND FAMILY THERAPIES Many therapeutic techniques can also be applied in a group context. Self-help and support groups, such as AA, engage many millions of people. Family therapy treats the family as an interactive system from which problems may arise. EVALUATING PSYCHOTHERAPIES Is Psychotherapy Effective? Because the positive testimonials of clients and therapists cannot prove that therapy is actually effective, psychologists have conducted hundreds of studies of psychotherapy’s outcomes. Meta-analyses of these studies reveal that (1) people who remain untreated often improve; (2) those who receive psychotherapy are more likely to improve, regardless of what kind of therapy they receive and for how long; (3) people with clear-cut specific problems often receive the greatest benefits from therapy; but (4) placebo treatments or the sympathy and friendly counsel of paraprofessionals also tend to produce more improvement than occurs when people receive no treatment. The Relative Effectiveness of Different Therapies Although no one type of therapy can be said to be most effective overall, some therapies are particularly well-suited to specific disorders. Behavioral conditioning, for example, is effective in treating phobias and compulsions. Evaluating Alternative Therapies Of the three alternative therapies considered—therapeutic touch, EMDR, and light exposure therapy—only light exposure therapy has held up under scientific testing. Commonalities Among Psychotherapies All types of psychotherapy seem to offer three benefits: new hope, a fresh perspective, and an empathic, trusting, caring relationship. Therapists do, however, differ in the values that influence their aims. Culture and Values in Psychotherapy Therapists differ in the values that influence their aims. Value differences may also create problems when a therapist from one culture works with a client from another culture. Before seeking therapy, one might ask about the therapist’s treatment approach and values, as well as the person’s credentials and fees. THE BIOMEDICAL THERAPIES Drug Therapies The most widely used biomedical therapies are the antipsychotic, antianxiety, and antidepressant drugs. A few drugs, such as lithium for bipolar disorder, have proven very effective in double-blind studies, though many drugs are hardly more effective than placebo treatments and some have serious side effects. Electroconvulsive Therapy ECT is a biomedical therapy in which a brief electric current is sent through the brain of an anesthetized patient. Although controversial, ECT remains an effective, last-resort treatment for many people with severe depression who have not responded to drug therapy. Researchers are also exploring newer alternatives, such as magnetic brain stimulation. Psychosurgery Although radical psychosurgical procedures such as lobotomy were once popular, neurosurgeons now rarely perform brain surgery to alleviate specific problems. Even when MRI-guided precision surgery is considered, it is a treatment of last resort because its effects are irreversible. PREVENTING PSYCHOLOGICAL DISORDERS Advocates of preventive mental health argue that many psychological disorders could be prevented. Their aim is to change oppressive, esteem-destroying environments into more benevolent, nurturing environments that foster individual growth and self-confidence. SOCIAL THINKING Social psychology is the study of how people think about, influence, and relate to one another. Attributing Behavior to Persons or to Situations We generally explain people’s behavior by attributing it either to internal dispositions or to external situations. In accounting for others’ actions, we often underestimate the influence of the situation, thus committing the fundamental attribution error. When we explain our own behavior, however, we more often point to the situation and not to ourselves. Attitudes and Actions Attitudes predict behavior only under certain conditions, as when other influences are minimized, when the attitude is specific to the behavior, and when people are aware of their attitudes. Studies of the foot-in-the-door phenomenon and of role playing reveal that our actions can also modify our attitudes, especially when we feel responsible for those actions. Cognitive dissonance theorists explain that behavior shapes attitudes because people feel discomfort when their actions go against their feelings and beliefs; they reduce the discomfort by bringing their attitudes more into line with what they have done. SOCIAL INFLUENCE Conformity and Obedience As suggestibility studies demonstrate, when we are unsure about our judgments, we are likely to adjust them toward the group standard. Solomon Asch found that under certain conditions people will conform to a group’s judgment even when it is clearly incorrect. We may conform either to gain social approval (normative social influence) or because we welcome the information that others provide (informational social influence). In Stanley Milgram’s famous experiments, people torn between obeying an experimenter and responding to another’s pleas to stop the shocks usually chose to obey orders, even though obedience supposedly meant harming the other person. Social influence is potent. Group Influence Experiments on social facilitation reveal that the presence of either observers or co-actors can arouse individuals, boosting their performance on easy tasks but hindering it on difficult ones. When people pool their efforts toward a group goal, social loafing may occur as some individuals take a free ride on others’ efforts. When a group experience arouses people and makes them anonymous, they may become less self-aware and self-restrained, a psychological state known as deindividuation. Within groups, discussions among like-minded members often produce group polarization, an enhancement of the group’s prevailing attitudes. This is one cause of groupthink, the tendency for harmony-seeking groups to make unrealistic decisions after suppressing dissenting information. The power of the group is great, but so is the power of the person. Even a small minority sometimes sways a group, especially when the minority expresses its views consistently. SOCIAL RELATIONS Prejudice Prejudice often arises as those who enjoy social and economic superiority attempt to justify the status quo. Even the temporary assignment of people to groups can cause an ingroup bias. Once established, the inertia of social influence often helps maintain prejudice. Prejudice may also focus the anger caused by frustration on a scapegoat. Newer research reveals how our ways of processing information—for example, by overestimating similarities when we categorize people or by noticing and remembering vivid cases—work to create stereotypes. In addition, favored social groups often rationalize their higher status with the just-world phenomenon. Aggression Aggressive behavior, like all behavior, is a product of nature and nurture. Although psychologists dismiss the idea that aggression is instinctual, aggressiveness is genetically influenced. Moreover, certain areas of the brain, when stimulated, activate or inhibit aggression, and these neural areas are biochemically influenced. A variety of psychological factors also fuel aggression’s fire. Aversive events heighten people’s hostility. Such stimuli are especially likely to trigger aggression in those rewarded for their own aggression, those who have learned aggression from role models, and those who have been influenced by media violence. Enacting violence in video games also heightens aggressive behavior. Conflict Conflicts between individuals and cultures often arise from malignant social processes. These include social traps, in which each party, by protecting and pursuing its self-interest, creates an outcome that no one wants. The spiral of conflict also feeds and is fed by distorted mirror-image perceptions, in which each party views itself as moral and the other as untrustworthy and evil-intentioned. Attraction Three factors affect our liking for one another. Proximity—geographical nearness—is conducive to attraction, partly because mere exposure to novel stimuli enhances liking. Physical attractiveness influences social opportunities and the way one is perceived. As acquaintanceship moves toward friendship, similarity of attitudes and interests greatly increases liking. We can view passionate love as an aroused state that we cognitively label as love. The strong affection of companionate love, which often emerges as a relationship matures, is enhanced by an equitable relationship and by intimate selfdisclosure. Altruism In response to incidents where bystanders did not intervene in emergencies, social psychologists undertook experiments that revealed a bystander effect: Any given bystander is less likely to help if others are present. The bystander effect is especially apparent in situations where the presence of others inhibits one’s noticing the event, interpreting it as an emergency, or assuming responsibility for offering help. Many factors, including mood, also influence one’s willingness to help someone in distress. Social exchange theory proposes that our social behaviors—even our helpful acts— maximize our benefits (which may include our own good feelings) and minimize our costs. Our desire to help is also affected by social norms, which prescribe reciprocating the help we have received and being socially responsible toward those in need. Peacemaking Enemies sometimes become friends, especially when the circumstances favor cooperation to achieve superordinate goals, understanding through communication, and reciprocated conciliatory gestures.