Psychology 1300 Final Review

How do cultural norms affect our behavior?

A culture is a set of behaviors, ideas, attitudes, values, and traditions shared by a group and transmitted from one generation to the next. Cultural norms are understood rules that inform members of a culture about accepted and expected behaviors. Cultures differ across time and space.

How can we describe data with measures of central tendency and variation?

A measure of central tendency is a single score that represents a whole set of scores. Three such measures are the mode (the most frequently occurring score), the mean (the arithmetic average), and the median (the middle score in a group of data).

How do different reinforcement schedules affect behavior?

A reinforcement schedule defines how often a response will be reinforced. In continuous reinforcement (reinforcing desired responses every time they occur), learning is rapid, but so is extinction if rewards cease. In partial (intermittent) reinforcement (reinforcing responses only sometimes), initial learning is slower, but the behavior is much more resistant to extinction. Fixed-ratio schedules reinforce behaviors after a set number of responses; variable-ratio schedules, after an unpredictable number. Fixed-interval schedules reinforce behaviors after set time periods; variable-interval schedules, after unpredictable time periods.

How is adolescence defined, and what physical changes mark this period?

Adolescence is the transition period from childhood to adulthood, extending from puberty to social independence. During puberty, both primary and secondary sex characteristics develop dramatically. Boys seem to benefit from "early" maturation, girls from "late" maturation. The brain's frontal lobes mature and myelin growth increases during adolescence and the early twenties, enabling improved judgment, impulse control, and long-term planning.

What themes and influences mark our social journey from early adulthood to death?

Adults do not progress through an orderly sequence of age-related social stages. Chance events can determine life choices. The social clock is a culture's preferred timing for social events, such as marriage, parenthood, and retirement. Adulthood's dominant themes are love and work, which Erikson called intimacy and generativity.

What is the energy that we see as visible light, and how does the eye transform light energy into neural messages?

After entering the eye and being focused by a lens, light energy particles (from a thin slice of the broad spectrum of electromagnetic energy) strike the eye's inner surface, the retina. The retina's light-sensitive rods and color-sensitive cones convert the light energy into neural impulses. The hue we perceive in a light depends on its wavelength, and its brightness depends on its intensity.

How do the eye and the brain process visual information?

After processing by bipolar and ganglion cells in the eyes' retina, neural impulses travel through the optic nerve, to the thalamus, and on to the visual cortex. In the visual cortex, feature detectors respond to specific features of the visual stimulus. Supercell clusters in other critical areas respond to more complex patterns. Through parallel processing, the brain handles many aspects of vision (color, movement, form, and depth) simultaneously. Other neural teams integrate the results, comparing them with stored information and enabling perceptions.

How do early experiences modify the brain?

As a child's brain develops, neural connections grow more numerous and complex. Experiences then trigger a pruning process, in which unused connections weaken and heavily used ones strengthen. Early childhood is an important period for shaping the brain, but throughout our lives our brain modifies itself in response to our learning.

How does memory change with age?

As the years pass, recall begins to decline, especially for meaningless information, but recognition memory remains strong. Older adults rely more on time management and memory cues to remember time-based and habitual tasks. Dementia and Alzheimer's disease are brain ailments, not normal parts of aging. Developmental researchers study age-related changes (such as memory) with cross-sectional studies (comparing people of different ages) and longitudinal studies (retesting the same people over a period of years). "Terminal decline" describes the cognitive decline in the final few years of life.

How do parent-infant attachment bonds form?

At about 8 months, soon after object permanence develops, children separated from their caregivers display stranger anxiety. Infants form attachments not simply because parents gratify biological needs but, more important, because they are comfortable, familiar, and responsive. Ducks and other animals have a more rigid attachment process, called imprinting, that occurs during a critical period.

How have psychologists studied attachment differences, and what have they learned?

Attachment has been studied in strange situation experiments, which show that some children are securely attached and others are insecurely attached. Infants' differing attachment styles reflect both their individual temperament and the responsiveness of their parents and child-care providers. Adult relationships seem to reflect the attachment styles of early childhood, lending support to Erik Erikson's idea that basic trust is formed in infancy by our experiences with responsive caregivers.

Does behavior depend on one's culture and gender?

Attitudes and behaviors may vary somewhat by gender or across cultures, but because of our shared human kinship, the underlying processes and principles are more similar than different.

What are the social tasks and challenges of adolescence?

Erikson theorized that each life stage has its own psychosocial task, and that a chief task of adolescence is solidifying one's sense of self—one's identity. This often means "trying on" a number of different roles. Social identity is the part of the self-concept that comes from a person's group memberships.

What are some newborn abilities, and how do researchers explore infants' mental abilities?

Babies are born with sensory equipment and reflexes that facilitate their survival and their social interactions with adults. For example, they quickly learn to discriminate their mother's smell and sound. Researchers use techniques that test habituation, such as the novelty-preference procedure, to explore infants' abilities.

How is our biological sex determined, and how do sex hormones influence gender development?

Biological sex is determined by the father's contribution to the twenty-third pair of chromosomes. The mother always contributes an X chromosome. The father may also contribute an X chromosome, producing a female, or a Y chromosome, producing a male by triggering additional testosterone release and the development of male sex organs. Sex-related genes and physiology influence behavioral and cognitive gender differences between males and females.

Does childhood neglect, abuse, or family disruption affect children's attachments?

Children are very resilient, but those who are moved repeatedly, severely neglected by their parents, or otherwise prevented from forming attachments by age 2 may be at risk for attachment problems.

What is the impact of prosocial modeling and of antisocial modeling?

Children tend to imitate what a model does and says, whether the behavior being modeled is prosocial (positive, constructive, and helpful) or antisocial. If a model's actions and words are inconsistent, children may imitate the hypocrisy they observe.

What are the basic components of classical conditioning, and what was behaviorism's view of learning?

Classical conditioning is a type of learning in which an organism comes to associate stimuli. In classical conditioning, an NS is a stimulus that elicits no response before conditioning. A UR is an event that occurs naturally (such as salivation), in response to some stimulus. A US is something that naturally and automatically (without learning) triggers the unlearned response (as food in the mouth triggers salivation). A CS is a previously neutral stimulus (such as a tone) that, after association with a US (such as food) comes to trigger a CR. A CR is the learned response (salivating) to the originally neutral (but now conditioned) stimulus. Ivan Pavlov's work on classical conditioning laid the foundation for behaviorism, the view that psychology should be an objective science that studies behavior without reference to mental processes. The behaviorists believed that the basic laws of learning are the same for all species, including humans.

How do biological constraints affect classical and operant conditioning?

Classical conditioning principles, we now know, are constrained by biological predispositions, so that learning some associations is easier than learning others. Learning is adaptive: Each species learns behaviors that aid its survival. Biological constraints also place limits on operant conditioning. Training that attempts to override biological constraints will probably not endure because animals will revert to predisposed patterns.

How do neuroscientists study the brain's connections to behavior and mind?

Clinical observations and lesioning reveal the general effects of brain damage. Electrical, chemical, or magnetic stimulation can also reveal aspects of information processing in the brain. MRI scans show anatomy. EEG, PET, and fMRI (functional MRI) recordings reveal brain function.

What are the key criticisms of evolutionary psychology?

Critics argue that evolutionary psychologists (1) start with an effect and work backward to an explanation, (2) do not recognize social and cultural influences, and (3) absolve people from taking responsibility for their sexual behavior. Evolutionary psychologists respond that understanding our predispositions can help us overcome them. They also cite the value of testable predictions based on evolutionary principles, as well as the coherence and explanatory power of those principles.

Why did Skinner's ideas provoke controversy, and how might his operant conditioning principles be applied at school, in sports, at work, and at home?

Critics of Skinner's principles believed the approach dehumanized people by neglecting their personal freedom and seeking to control their actions. Skinner replied that people's actions are already controlled by external consequences, and that reinforcement is more humane than punishment as a means for controlling behavior. In school, teachers can use shaping techniques to guide students' behaviors, and they can use interactive software and websites to provide immediate feedback. In sports, coaches can build players' skills and self-confidence by rewarding small improvements. At work, managers can boost productivity and morale by rewarding well-defined and achievable behaviors. At home, parents can reward desired behaviors but not undesirable ones. We can shape our own behaviors by stating our goals, monitoring the frequency of desired behaviors, reinforcing desired behaviors, and gradually reducing rewards as behaviors become habitual.

How do we use binocular and monocular cues to perceive the world in three dimensions and perceive motion?

Depth perception is our ability to see objects in three dimensions and judge distance. The visual cliff and other research demonstrate that many species perceive the world in three dimensions at, or very soon after, birth. Binocular cues, such as retinal disparity, are depth cues that rely on information from both eyes. Monocular cues (such as relative size, interposition, relative height, relative motion, linear perspective, and light and shadow) let us judge depth using information transmitted by only one eye. As objects move, we assume that shrinking objects are retreating and enlarging objects are approaching. A quick succession of images on the retina can create an illusion of movement, as in stroboscopic movement or the phi phenomenon.

How do psychologists use case studies, naturalistic observation, and surveys to observe and describe behavior, and why is random sampling important?

Descriptive methods, which include case studies, naturalistic observations, and surveys, show us what can happen, and they may offer ideas for further study. The best basis for generalizing about a population is a representative sample; in a random sample, every person in the entire population being studied has an equal chance of participating. Descriptive methods cannot show cause and effect because researchers cannot control variables.

What three issues have engaged developmental psychologists?

Developmental psychologists study physical, mental, and social changes throughout the life span. They focus on three issues: nature and nurture (the interaction between our genetic inheritance and our experiences); continuity and stages (whether development is gradual and continuous or a series of relatively abrupt changes); and stability and change (whether our traits endure or change as we age).

How do parents and peers influence adolescents?

During adolescence, parental influence diminishes and peer influence increases. Adolescents adopt their peers' ways of dressing, acting, and communicating. Parents have more influence in religion, politics, and college and career choices.

How did psychology continue to develop from the 1920s through today?

Early researchers define psychology as a "science of mental life." In the 1920s, under the influence of John B. Watson and the behaviorists, the field's focus changed to the "scientific study of observable behavior." In the 1960s, the humanistic psychologists and the cognitive psychologists revived interest in the study of mental processes. Psychology is now defined as the science of behavior and mental processes.

How do evolutionary psychologists use natural selection to explain behavior tendencies?

Evolutionary psychologists seek to understand how our traits and behavior tendencies are shaped by natural selection, as genetic variations increasing the odds of reproducing and surviving are most likely to be passed on to future generations. Some variations arise from mutations (random errors in gene replication), others from new gene combinations at conception. Humans share a genetic legacy and are predisposed to behave in ways that promoted our ancestors' surviving and reproducing. Charles Darwin's theory of evolution is an organizing principle in biology. He anticipated today's application of evolutionary principles in psychology.

What does research on restored vision, sensory restriction, and perceptual adaptation reveal about the effects of experience on perception?

Experience guides our perceptual interpretations. People blind from birth who gained sight after surgery lack the experience to visually recognize shapes, forms, and complete faces. Sensory restriction research indicates that there is a critical period for some aspects of sensory and perceptual development. Without early stimulation, the brain's neural organization does not develop normally. People given glasses that shift the world slightly to the left or right, or even upside-down, experience perceptual adaptation. They are initially disoriented, but they manage to adapt to their new context.

What are some ways in which males and females tend to be alike and to differ?

Gender refers to the characteristics, whether biologically or socially influenced, by which people define male and female. We are more alike than different, thanks to our similar genetic makeup—we see, hear, learn, and remember similarly. Males and females do differ in body fat, muscle, height, age of onset of puberty, and life expectancy; in vulnerability to certain disorders; and in aggression, social power, and social connectedness.

How do gender roles and gender typing influence gender development?

Gender roles, the behaviors a culture expects from its males and females, vary across place and time. Social learning theory proposes that we learn gender identity—our sense of being male or female—as we learn other things: through reinforcement, punishment, and observation. Critics argue that cognition also plays a role because modeling and rewards cannot explain gender typing. Transgender people's gender identity or expression differs from their birth sex.

What are genes, and how do behavior geneticists explain our individual differences?

Genes are the biochemical units of heredity that make up chromosomes, the threadlike coils of DNA. When genes are "turned on" (expressed), they provide the code for creating the proteins that form our body's building blocks. Most human traits are influenced by many genes acting together. Behavior geneticists seek to quantify genetic and environmental influences on our traits, in part through studies of identical (monozygotic) twins, fraternal (dizygotic) twins, and adoptive families. Shared family environments have little effect on personality, and the stability of temperament suggests a genetic predisposition.

How did the Gestalt psychologists understand perceptual organization, and how do figure-ground and grouping principles contribute to our perceptions?

Gestalt psychologists searched for rules by which the brain organizes fragments of sensory data into gestalts (from the German word for "whole"), or meaningful forms. In pointing out that the whole may exceed the sum of its parts, they noted that we filter sensory information and construct our perceptions. To recognize an object, we must first perceive it (see it as a figure) as distinct from its surroundings (the ground). We bring order and form to stimuli by organizing them into meaningful groups, following such rules as proximity, continuity, and closure.

What is heritability, and how does it relate to individuals and groups?

Heritability describes the extent to which variation among members of a group can be attributed to genes. Heritable individual differences (in traits such as height or intelligence) do not necessarily imply heritable group differences. Genes mostly explain why some people are taller than others, but not why people are taller today than they were a century ago.

How do hindsight bias, overconfidence, and the tendency to perceive order in random events illustrate why science-based answers are more valid than those based on intuition and common sense?

Hindsight bias (also called the "I-knew-it-all-along phenomenon") is the tendency to believe, after learning an outcome, that we would have foreseen it. Overconfidence in our judgments results partly from our bias to seek information that confirms them. These tendencies, plus our eagerness to perceive patterns in random events, lead us to overestimate our intuition. Although limited by the testable questions it can address, scientific inquiry can help us overcome our intuition's biases and shortcomings.

To what extent can a damaged brain reorganize itself, and what is neurogenesis?

If one hemisphere is damaged early in life, the other will pick up many of its functions by reorganizing or building new pathways. This plasticity diminishes later in life. The brain sometimes mends itself by forming new neurons, a process known as neurogenesis.

What are positive and negative correlations, and why do they enable prediction but not cause-effect explanation?

In a positive correlation, two factors rise or fall together. In a negative correlation, one item rises as the other falls. Scatterplots can help us to see correlations. A correlation coefficient can describe the strength and direction of a relationship between two variables, from +1.00 (a perfect positive correlation) through zero (no correlation at all) to −1.00 (a perfect negative correlation). A correlation can indicate the possibility of a cause-effect relationship, but it does not prove the direction of the influence, or whether an underlying third factor may explain the correlation.

In classical conditioning, what are the processes of acquisition, extinction, spontaneous recovery, generalization, and discrimination?

In classical conditioning, acquisition is associating an NS with the US so that the NS begins triggering the CR. Acquisition occurs most readily when the NS is presented just before (ideally, about a half-second before) a US, preparing the organism for the upcoming event. This finding supports the view that classical conditioning is biologically adaptive. Through higher-order conditioning, a new NS can become a new CS. Extinction is diminished responding when the CS no longer signals an impending US. Spontaneous recovery is the appearance of a formerly extinguished response, following a rest period. Generalization is the tendency to respond to stimuli that are similar to a CS. Discrimination is the learned ability to distinguish between a CS and other irrelevant stimuli.

How do cognitive processes affect classical and operant conditioning?

In classical conditioning, animals may learn when to expect a US and may be aware of the link between stimuli and responses. In operant conditioning, cognitive mapping and latent learning research demonstrate the importance of cognitive processes in learning. Other research shows that excessive rewards (driving extrinsic motivation) can undermine intrinsic motivation.

From the perspectives of Piaget, Vygotsky, and today's researchers, how does a child's mind develop?

In his theory of cognitive development, Jean Piaget proposed that children actively construct and modify their understanding of the world through the processes of assimilation and accommodation. They form schemas that help them organize their experiences. Progressing from the simplicity of the sensorimotor stage of the first two years, in which they develop object permanence, children move to more complex ways of thinking. In the pre-operational stage (about age 2 to about 6 or 7), they develop a theory of mind, but they are egocentric and unable to perform simple logical operations. At about age 7, they enter the concrete operational stage and are able to comprehend the principle of conservation. By about age 12, children enter the formal operational stage and can reason systematically. Research supports the sequence Piaget proposed, but it also shows that young children are more capable, and their development more continuous, than he believed. Lev Vygotsky's studies of child development focused on the ways a child's mind grows by interacting with the social environment. In his view, parents and caretakers provide temporary scaffolds enabling children to step to higher levels of learning.

What is observational learning, and how do some scientists believe it is enabled by mirror neurons?

In observational learning, as we observe and imitate others we learn to anticipate a behavior's consequences because we experience vicarious reinforcement or vicarious punishment. Our brain's frontal lobes have a demonstrated ability to mirror the activity of another's brain. The same areas fire when we perform certain actions (such as responding to pain or moving our mouth to form words), as when we observe someone else performing those actions.

How does operant conditioning differ from classical conditioning?

In operant conditioning, an organism learns associations between its own behavior and resulting events; this form of conditioning involves operant behavior (behavior that operates on the environment, producing rewarding or punishing consequences). In classical conditioning, the organism forms associations between stimuli—events it does not control; this form of conditioning involves respondent behavior (automatic responses to some stimulus).

How is operant behavior reinforced and shaped?

In operant conditioning, behaviors followed by reinforcers increase; those followed by punishers often decrease. Expanding on Edward Thorndike's law of effect, B. F. Skinner and others found that the behavior of rats or pigeons placed in an operant chamber (Skinner box) can be shaped by using reinforcers to guide closer and closer approximations of the desired behavior.

What is included in the biopsychosocial approach to development?

Individual development results from the interaction of biological, psychological, and social-cultural influences. Biological influences include our shared human genome; individual variations; prenatal environment; and sex-related genes, hormones, and physiology. Psychological influences include gene-environment interactions; the effect of early experiences on neural networks; responses evoked by our own characteristics, such as gender and temperament; and personal beliefs, feelings, and expectations. Social-cultural influences include parental and peer influences; cultural traditions and values; and cultural gender norms.

What is learning, and what are some basic forms of learning?

Learning is the process of acquiring new and relatively enduring information or behaviors. In associative learning, we learn that certain events occur together. In classical conditioning, we learn to associate two or more stimuli (a stimulus is any event or situation that evokes a response). In operant conditioning, we learn to associate a response and its consequences. Through cognitive learning, we acquire mental information that guides our behavior. For example, in observational learning, we learn new behaviors by observing events and watching others.

How might an evolutionary psychologist explain gender differences in sexuality and mating preferences?

Men tend to have a recreational view of sexual activity; women tend to have a relational view. Evolutionary psychologists reason that men's attraction to multiple healthy, fertile-appearing partners increases their chances of spreading their genes widely. Because women incubate and nurse babies, they increase their own and their children's chances of survival by searching for mates with the potential for long-term investment in their joint offspring.

What is the promise of molecular genetics research?

Molecular geneticists study the molecular structure and function of genes, including those that affect behavior. Psychologists and molecular geneticists are cooperating to identify specific genes—or more often, teams of genes—that put people at risk for disorders.

What physical and sensory changes occur during middle and late adulthood?

Muscular strength, reaction time, sensory abilities, and cardiac output begin to decline in the late twenties and continue to decline throughout middle adulthood (roughly age 40 to 65) and late adulthood (the years after 65). Women's period of fertility ends with menopause around age 50; men have no similar age-related sharp drop in hormone levels or fertility. In late adulthood, the immune system weakens, increasing susceptibility to life-threatening illnesses. Chromosome tips (telomeres) wear down, reducing the chances of normal genetic replication. But for some, longevity-supporting genes, low stress, and good health habits enable better health in later life.

What are neurons, and how do they transmit information?

Neurons are the elementary components of the nervous system, the body's speedy electrochemical information system. A neuron receives signals through its branching dendrites, and sends signals through its axons. Some axons are encased in a myelin sheath, which enables faster transmission. If the combined received signals exceed a minimum threshold, the neuron fires, transmitting an electrical impulse (the action potential) down its axon by means of a chemistry-to-electricity process. The neuron's reaction is an all-or-none process.

How do neurotransmitters influence behavior, and how do drugs and other chemicals affect neurotransmission?

Neurotransmitters travel designated pathways in the brain and may influence specific behaviors and emotions. Acetylcholine affects muscle action, learning, and memory. Endorphins are natural opiates released in response to pain and exercise. Drugs and other chemicals affect brain chemistry at synapses. Agonists excite by mimicking particular neurotransmitters or by blocking their reuptake. Antagonists inhibit a particular neurotransmitter's release or block its effect.

What are the absolute and difference thresholds, and do stimuli below the absolute threshold have any influence on us?

Our absolute threshold for any stimulus is the minimum stimulation necessary for us to be consciously aware of it 50 percent of the time. Signal detection theory predicts how and when we will detect a faint stimulus amid background noise. Individual absolute thresholds vary, depending on the strength of the signal and also on our experience, expectations, motivation, and alertness. Our difference threshold (also called just noticeable difference, or jnd) is the difference we can discern between two stimuli 50 percent of the time. Weber's law states that two stimuli must differ by a constant proportion (not a constant amount) to be perceived as different. Priming shows that we can process some information from stimuli below our absolute threshold for conscious awareness. But the effect is too fleeting to enable people to exploit us with subliminal messages.

How do heredity and environment work together?

Our genetic predispositions and our surrounding environments interact. Environments can trigger gene activity, and genetically influenced traits can evoke responses from others. The field of epigenetics studies the influences on gene expression that occur without changes in DNA.

How do we sense touch?

Our sense of touch is actually several senses—pressure, warmth, cold, and pain—that combine to produce other sensations, such as "hot."

What three steps are basic to all our sensory systems?

Our senses (1) receive sensory stimulation (often using specialized receptor cells); (2) transform that stimulation into neural impulses; and (3) deliver the neural information to the brain. Transduction is the process of converting one form of energy into another. Researchers in psychophysics study the relationships between stimuli's physical characteristics and our psychological experience of them.

How can we best understand and control pain?

Pain reflects bottom-up sensations (such as input from nociceptors, the sensory receptors that detect hurtful temperatures, pressure, or chemicals) and top-down processes (such as experience, attention, and culture). 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.

What are the claims of ESP, and what have most research psychologists concluded after putting these claims to the test?

Parapsychology is the study of paranormal phenomena, including extrasensory perception (ESP) and psychokinesis. The three most testable forms of ESP are telepathy (mind-to-mind communication), clairvoyance (perceiving remote events), and precognition (perceiving future events). Skeptics argue that (1) to believe in ESP, you must believe the brain is capable of perceiving without sensory input; (2) Researchers have been unable to replicate ESP phenomena under controlled conditions.

What are parenting styles, and how are children's traits related to them?

Parenting styles—authoritarian, permissive, and authoritative—reflect varying degrees of control. Children with high self-esteem tend to have authoritative parents and to be self-reliant and socially competent, but the direction of cause and effect in this relationship is not clear.

In what ways do parents and peers shape children's development?

Parents influence their children in areas such as manners and political and religious beliefs, but not in other areas, such as personality. As children attempt to fit in with their peers, they tend to adopt their culture—styles, accents, slang, attitudes. By choosing their children's neighborhoods and schools, parents exert some influence over peer group culture.

Why does Pavlov's work remain so important, and what have been some applications of his work to human health and well-being?

Pavlov taught us that significant psychological phenomena can be studied objectively, and that classical conditioning is a basic form of learning that applies to all species. Classical conditioning techniques are used to improve human health and well-being in many areas, including behavioral therapy for some types of psychological disorders. The body's immune system may also respond to classical conditioning.

A loved one's death triggers what range of reactions?

People do not grieve in predictable stages, as was once supposed. Strong expressions of emotion do not purge grief, and bereavement therapy is not significantly more effective than grieving without such aid. Erikson viewed the late-adulthood psychosocial task as developing a sense of integrity (versus despair).

How do perceptual constancies help us organize our sensations into meaningful perceptions?

Perceptual constancy enables us to perceive objects as stable despite the changing image they cast on our retinas. Color constancy is our ability to perceive consistent color in objects, even though the lighting and wavelengths shift. Brightness (or lightness) constancy is our ability to perceive an object as having a constant lightness even when its illumination—the light cast upon it—changes. Our brain constructs our experience of an object's color or brightness through comparisons with other surrounding objects. Shape constancy is our ability to perceive familiar objects (such as an opening door) as unchanging in shape. Size constancy is perceiving objects as unchanging in size despite their changing retinal images. Knowing an object's size gives us clues to its distance; knowing its distance gives clues about its size, but we sometimes misread monocular distance cues and reach the wrong conclusions, as in the Moon illusion.

How do our expectations, contexts, emotions, and motivation influence our perceptions?

Perceptual set is a mental predisposition that functions as a lens through which we perceive the world. Our learned concepts (schemas) prime us to organize and interpret ambiguous stimuli in certain ways. Our physical and emotional context, as well as our motivation, can create expectations and color our interpretation of events and behaviors.

How did Piaget, Kohlberg, and later researchers describe adolescent cognitive and moral development?

Piaget theorized that adolescents develop a capacity for formal operations and that this development is the foundation for moral judgment. Lawrence Kohlberg proposed a stage theory of moral reasoning, from a preconventional morality of self-interest, to a conventional morality concerned with upholding laws and social rules, to (in some people) a postconventional morality of universal ethical principles. Other researchers believe that morality lies in moral intuition and moral action as well as thinking. Some critics argue that Kohlberg's postconventional level represents morality from the perspective of individualist, middle-class males.

What theories help us understand pitch perception?

Place theory explains how we hear high-pitched sounds, and frequency theory explains how we hear low-pitched sounds. (A combination of the two theories explains how we hear pitches in the middle range.) Place theory proposes that our brain interprets a particular pitch by decoding the place where a sound wave stimulates the cochlea's basilar membrane. Frequency theory proposes that the brain deciphers the frequency of the neural impulses traveling up the auditory nerve to the brain.

How do theories advance psychological science?

Psychological theories are explanations that apply an integrated set of principles to organize observations and generate hypotheses—predictions that can be used to check the theory or produce practical applications of it. By testing their hypotheses, researchers can confirm, reject, or revise their theories. To enable other researchers to replicate the studies, researchers report them using precise operational definitions of their procedures and concepts. If others achieve similar results, confidence in the conclusion will be greater.

Why are psychologists concerned with human biology?

Psychologists working from a biological perspective study the links between biology and behavior. We are biopsychosocial systems, in which biological, psychological, and social-cultural factors interact to influence behavior.

Is psychology free of value judgments?

Psychologists' values influence their choice of research topics, their theories and observations, their labels for behavior, and their professional advice. Applications of psychology's principles have been used mainly in the service of humanity.

What is psychology's historic big issue?

Psychology's biggest and most enduring issue has been the nature—nurture issue, which focuses on the relative contributions of genes and experience. Today's science emphasizes the interaction of genes and experiences in specific environments. Charles Darwin's view that natural selection shapes behaviors as well as bodies is an important principle in contemporary psychology.

How does punishment differ from negative reinforcement, and how does punishment affect behavior?

Punishment administers an undesirable consequence (such as spanking) or withdraws something desirable (such as taking away a favorite toy) in an attempt to decrease the frequency of a behavior (a child's disobedience). Negative reinforcement (taking an aspirin) removes an aversive stimulus (a headache). This desired consequence (freedom from pain) increases the likelihood that the behavior (taking aspirin to end pain) will be repeated. Punishment can have undesirable side effects, such as suppressing rather than changing unwanted behaviors; teaching aggression; creating fear; encouraging discrimination (so that the undesirable behavior appears when the punisher is not present); and fostering depression and feelings of helplessness.

How does day care affect children?

Quality day care, with responsive adults interacting with children in a safe and stimulating environment, does not appear to harm children's thinking and language skills. Some studies have linked extensive time in day care with increased aggressiveness and defiance, but other factors—the child's temperament, the parents' sensitivity, and the family's economic and educational levels and culture—also matter.

How do positive and negative reinforcement differ, and what are the basic types of reinforcers?

Reinforcement is any consequence that strengthens behavior. Positive reinforcement adds a desirable stimulus to increase the frequency of a behavior. Negative reinforcement removes an aversive stimulus to increase the frequency of a behavior. Primary reinforcers (such as receiving food when hungry or having nausea end during an illness) are innately satisfying—no learning is required. Conditioned (or secondary) reinforcers (such as cash) are satisfying because we have learned to associate them with more basic rewards (such as the food or medicine we buy with them). Immediate reinforcers (such as a purchased treat) offer immediate payback; delayed reinforcers (such as a weekly paycheck) require the ability to delay gratification.

Can laboratory experiments illuminate everyday life?

Researchers intentionally create a controlled, artificial environment in the laboratory in order to test general theoretical principles. These general principles help explain everyday behaviors.

How do children's self-concepts develop?

Self-concept, an understanding and evaluation of who we are, emerges gradually. At 15 to 18 months, children recognize themselves in a mirror. By school age, they can describe many of their own traits, and by age 8 to 10 their self-image is stable.

Do self-confidence and life satisfaction vary with life stages?

Self-confidence tends to strengthen across the life span. Surveys show that life satisfaction is unrelated to age. Positive emotions increase after midlife and negative ones decrease.

What are sensation and perception? What do we mean by bottom-up processing and top-down processing?

Sensation is the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment. Perception is the process of organizing and interpreting this information, enabling recognition of meaningful events. Sensation and perception are actually parts of one continuous process. Bottom-up processing is sensory analysis that begins at the entry level, with information flowing from the sensory receptors to the brain. Top-down processing is information processing guided by high-level mental processes, as when we construct perceptions by filtering information through our experience and expectations.

What is the function of sensory adaptation?

Sensory adaptation (our diminished sensitivity to constant or routine odors, sounds, and touches) focuses our attention on informative changes in our environment.

Why do psychologists study animals, and what ethical guidelines safeguard human and animal research participants?

Some psychologists are primarily interested in animal behavior; others want to better understand the physiological and psychological processes shared by humans and other species. Government agencies have established standards for animal care and housing. Professional associations and funding agencies also establish guidelines for protecting animals' well-being. The APA ethics code outlines standards for safeguarding human participants' well-being, including obtaining their informed consent and debriefing them later.

What are the characteristics of air pressure waves that we hear as sound, and how does the ear transform sound energy into neural messages?

Sound waves are bands of compressed and expanded air. Our ears detect these changes in air pressure and transform them into neural impulses, which the brain decodes as sound. Sound waves vary in amplitude, which we perceive as differing loudness, and in frequency, which we experience as differing pitch.

How do we locate sounds?

Sound waves strike one ear sooner and more intensely than the other. The brain analyzes the minute differences in the sounds received by the two ears and computes the sound's source.

What do split brains reveal about the functions of our two brain hemispheres?

Split-brain research (experiments on people with a severed corpus callosum) has 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.

How do we experience taste and smell, and how do they interact?

Taste and smell are chemical senses. Taste is a composite of five basic sensations—sweet, sour, salty, bitter, and umami—and of the aromas that interact with information from the taste receptor cells of the taste buds. There are no basic sensations for smell. We have some 5 million olfactory receptor cells, with about 350 different receptor proteins. Odor molecules trigger combinations of receptors, in patterns that the olfactory cortex interprets. The receptor cells send messages to the brain's olfactory bulb, then to the temporal lobe, and to parts of the limbic system. The influence of smell on our sense of taste is an example of sensory interaction. Embodied cognition is the influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.

What theories help us understand color vision?

The Young-Helmholtz trichromatic (three-color) theory proposed that the retina contains three types of color receptors. Contemporary research has found three types of cones, each most sensitive to the wavelengths of one of the three primary colors of light (red, green, or blue). Hering's opponent-process theory proposed three additional color processes (red-versus-green, blue-versus-yellow, black-versus-white). Contemporary research has confirmed that, en route to the brain, neurons in the retina and the thalamus code the color-related information from the cones into pairs of opponent colors.

What are psychology's levels of analysis and related perspectives?

The biopsychosocial approach integrates information from three differing but complementary levels of analysis: the biological, psychological, and social-cultural. This approach offers a more complete understanding than could usually be reached by relying on only one of psychology's current perspectives (neuroscience, evolutionary, behavior genetics, psychodynamic, behavioral, cognitive, and social-cultural).

During infancy and childhood, how do the brain and motor skills develop?

The brain's nerve cells are sculpted by heredity and experience. Their interconnections multiply rapidly after birth, a process that continues until puberty, when a pruning process begins shutting down unused connections. Complex motor skills—sitting, standing, walking—develop in a predictable sequence, though the timing of that sequence is a function of individual maturation and culture. We have no conscious memories of events occurring before about age 3-1/2, in part because major brain areas have not yet matured.

What structures make up the brainstem, and what are the functions of the brainstem, thalamus, and cerebellum?

The brainstem, the oldest part of the brain, is responsible for automatic survival functions. Its components are the medulla (which controls heartbeat and breathing), the pons (which helps coordinate movements), and the reticular formation (which affects arousal). The thalamus, sitting above the brainstem, acts as the brain's sensory switchboard. The cerebellum, attached to the rear of the brainstem, coordinates muscle movement and balance and also helps process sensory information.

What are the functions of the nervous system's main divisions, and what are the three main types of neurons?

The central nervous system (CNS)—the brain and the spinal cord—is the nervous system's decision maker. The peripheral nervous system (PNS), which connects the CNS to the rest of the body by means of nerves, gathers information and transmits CNS decisions to the rest of the body. The two main PNS divisions are the somatic nervous system (which enables voluntary control of the skeletal muscles) and the autonomic nervous system (which controls involuntary muscles and glands by means of its sympathetic and parasympathetic divisions). Neurons cluster into working networks. There are three types of neurons: (1) Sensory neurons carry incoming information from sense receptors to the brain and spinal cord. (2) Motor neurons carry information from the brain and spinal cord out to the muscles and glands. (3) Interneurons communicate within the brain and spinal cord and between sensory and motor neurons. In addition, glial cells support, nourish, and protect neurons and may also play a role in learning and thinking.

What are the functions of the various cerebral cortex regions?

The cerebral cortex has two hemispheres, and each hemisphere has four lobes: the frontal, parietal, occipital, and temporal. Each lobe performs many functions and interacts with other areas of the cortex. The motor cortex, at the rear of the frontal lobes, controls voluntary movements. The sensory cortex, at the front of the parietal lobes, registers and processes body touch and movement sensations. Body parts requiring precise control (in the motor cortex) or those that are especially sensitive (in the sensory cortex) occupy the greatest amount of space. Most of the brain's cortex—the major portion of each of the four lobes—is devoted to uncommitted association areas, which integrate information involved in learning, remembering, thinking, and other higher-level functions. Our mental experiences arise from coordinated brain activity.

How does the endocrine system transmit information and interact with the nervous system?

The endocrine system is a set of glands that secrete hormones into the bloodstream, where they travel through the body and affect other tissues, including the brain. The endocrine system's master gland, the pituitary, influences hormone release by other glands. In an intricate feedback system, the brain's hypothalamus influences the pituitary gland, which influences other glands, which release hormones, which in turn influence the brain.

What is the course of prenatal development, and how do teratogens affect that development?

The life cycle begins at conception, when one sperm cell unites with an egg to form a zygote. The zygote's inner cells become the embryo, and in the next 6 weeks, body organs begin to form and function. By 9 weeks, the fetus is recognizably human. Teratogens are potentially harmful agents that can pass through the placental screen and harm the developing embryo or fetus, as happens with fetal alcohol syndrome.

What are the limbic system's structures and functions?

The limbic system is linked to emotions, memory, and drives. Its neural centers include the hippocampus (which processes conscious memories); the amygdala (involved in responses of aggression and fear); and the hypothalamus (involved in various bodily maintenance functions, pleasurable rewards, and the control of the endocrine system). The pituitary (the "master gland") controls the hypothalamus by stimulating it to trigger the release of hormones.

How do the scientific attitude's three main components relate to critical thinking?

The scientific attitude equips us to be curious, skeptical, and humble in scrutinizing competing ideas or our own observations. This attitude carries into everyday life as critical thinking, which puts ideas to the test by examining assumptions, discerning hidden values, evaluating evidence, and assessing conclusions.

How can psychological principles help you learn and remember?

The testing effect shows that learning and memory are enhanced by actively retrieving, rather than simply rereading, previously studied material. The SQ3R study method—survey, question, read, retrieve, and review—applies principles derived from memory research. Four additional tips are (1) distribute your study time; (2) learn to think critically; (3) process class information actively; and (4) overlearn.

What is emerging adulthood?

The transition from adolescence to adulthood is now taking longer. Emerging adulthood is the period from age 18 to the mid-twenties, when many young people are not yet fully independent. But critics note that this stage is found mostly in today's Western cultures.

How do we sense our body's position and movement?

Through kinesthesis, we sense the position and movement of our body parts. We monitor our body's position and movement, and maintain our balance with our vestibular sense.

What are the characteristics of experimentation that make it possible to isolate cause and effect?

To discover cause-effect relationships, psychologists conduct experiments, manipulating one or more factors of interest and controlling other factors. Using random assignment, they can minimize confounding variables, such as preexisting differences between the experimental group (exposed to the treatment) and the control group (given a placebo or different version of the treatment). The independent variable is the factor the experimenter manipulates to study its effect; the dependent variable is the factor the experimenter measures to discover any changes occurring in response to the manipulations. Studies may use a double-blind procedure to avoid the placebo effect and researcher's bias.

How do we know whether an observed difference can be generalized to other populations?

To feel confident about generalizing an observed difference to other populations, we would want to know that the sample studied was representative of the larger population being studied; that the observations, on average, had low variability; that the sample consisted of more than a few cases; and that the observed difference was statistically significant.

How do nerve cells communicate with other nerve cells?

When action potentials reach the end of an axon (the axon terminals), they stimulate the release of neurotransmitters. These chemical messengers carry a message from the sending neuron across a synapse to receptor sites on a receiving neuron. The sending neuron, in a process called reuptake, then normally reabsorbs the excess neurotransmitter molecules in the synaptic gap. If incoming signals are strong enough, the receiving neuron generates its own action potential and relays the message to other cells.

What are some important milestones in psychology's early development?

Wilhelm Wundt established the first psychological laboratory in 1879 in Germany. Two early schools were structuralism and functionalism.

How do individualist and collectivist cultures influence people?

Within any culture, the degree of individualism or collectivism varies from person to person. Cultures based on self-reliant individualism, like those found in North America and Western Europe, tend to value personal independence and individual achievement. They define identity in terms of self-esteem, personal goals and attributes, and personal rights and liberties. Cultures based on socially connected collectivism, like those in many parts of Asia and Africa, tend to value interdependence, tradition, and harmony, and they define identity in terms of group goals, commitments, and belonging to one's group.

What are psychology's main subfields?

Within the science of psychology, researchers may conduct basic research to increase the field's knowledge base (often in biological, developmental, cognitive, personality, and social psychology) or applied research to solve practical problems (in industrial-organizational psychology and other areas).