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Essentials of Understanding Psychology by Feldman (13th edition) is the 13th edition of the Essentials of Understanding Psychology textbook authored by Robert S. Feldman, University of Massachusetts Amherst, and published by McGraw-Hill Education, New York, NY in 2019.

  • Abnormal behavior. Behavior that causes people to experience distress and prevents them from functioning in their daily lives.
  • Absolute threshold. The smallest intensity of a stimulus that must be present for the stimulus to be detected.
  • Action potential. An electric nerve impulse that travels through a neuron's axon when it is set off by a "trigger," changing the neuron's charge from negative to positive.
  • Activation-synthesis theory. Hobson's theory that the brain produces random electrical energy during REM sleep that stimulates memories stored in the brain.
  • Activity theory of aging. The theory that suggests that successful aging is characterized by maintaining the interests and activities of earlier stages of life.
  • Adaptation. An adjustment in sensory capacity after prolonged exposure to unchanging stimuli.
  • Addictive drugs. Drugs that produce a biological or psychological dependence in the user so that withdrawal from them leads to a craving for the drug that, in some cases, may be nearly irresistible.
  • Adolescence. The developmental stage between childhood and adulthood.
  • Age of viability. The point at which a fetus can survive if born prematurely.
  • Aggression. The intentional injury of, or harm to, another person.
  • Algorithm. A rule that, if applied appropriately, guarantees a solution to a problem.
  • All-or-none law. The rule that neurons are either on or off.
  • Altruism. Behavior meant to help another person without regard for self-interest.
  • Alzheimer's disease. A progressive brain disorder that leads to a gradual and irreversible decline in cognitive abilities.
  • Amnesia. Memory loss that occurs without other mental difficulties.
  • Anal stage. According to Freud, a stage from age 12 to 18 months to 3 years of age, in which a child's pleasure is centered on the anus.
  • Androgens. Male sex hormones secreted by the testes.
  • Anorexia nervosa. A severe eating disorder in which people may refuse to eat while denying that their behavior and appearance -- which can become skeleton- like -- are unusual.
  • Anterograde amnesia. Amnesia in which memory is lost for events that follow an injury.
  • Antianxiety drugs. Drugs that reduce the level of anxiety a person experiences essentially by reducing excitability and increasing feelings of well-being.
  • Antidepressant drugs. Medications that improve a severely depressed patient's mood and feeling of well-being.
  • Antipsychotic drugs. Drugs that temporarily reduce psychotic symptoms such as agitation, hallucinations, and delusions.
  • Antisocial personality disorder. A disorder in which individuals show no regard for the moral and ethical rules of society or the rights of others.
  • Anxiety disorder. The occurrence of anxiety without an obvious external cause that affects daily functioning.
  • Archetypes. According to Jung, universal symbolic representations of particular types of people, objects, ideas, or experiences.
  • Archival research. Research in which existing data, such as census documents, college records, and newspaper articles, are examined to test a hypothesis.
  • Arousal approaches to motivation. The belief that we try to maintain certain levels of stimulation and activity.
  • Association areas . One of the major regions of the cerebral cortex; the site of the higher mental processes, such as thought, language, memory, and speech.
  • Assumed-similarity bias. The tendency to think of people as being similar to oneself even when meeting them for the first time.
  • Attachment. The positive emotional bond that develops between a child and a particular individual.
  • Attention-deficit hyperactivity disorder (ADHD). A disorder marked by inattention, impulsiveness, a low tolerance for frustration, and a great deal of inappropriate activity.
  • Attitudes. Evaluations of people, objects, ideas, and behavior.
  • Attribution theory. The theory that considers how we decide, on the basis of samples of a person's behavior, what the specific causes of that behavior are.
  • Authoritarian parents. Parents who are rigid and punitive and value unquestioning obedience from their children.
  • Authoritative parents. Parents who are firm, set clear limits, reason with their children, and explain things to them.
  • Autism. A severe developmental disability that impairs children's ability to communicate and relate to others.
  • Autobiographical memory. Our recollections of our own life experiences.
  • Autonomic division. The part of the peripheral nervous system that controls involuntary movement of the heart, glands, lungs, and other organs.
  • Autonomy-versus-shame-and-doubt stage. The period during which, according to Erikson, toddlers (ages 1½ to 3 years) develop independence and autonomy if exploration and freedom are encouraged or shame and self-doubt if they are restricted and overprotected.
  • Aversive conditioning. A form of therapy that reduces the frequency of undesired behavior by pairing an aversive, unpleasant stimulus with undesired behavior.
  • Axon. The part of the neuron that carries messages destined for other neurons.
  • Babble. Meaningless speechlike sounds made by children from around the age of 3 months through 1 year.
  • Background stressors ("daily hassles"). Everyday annoyances, such as being stuck in traffic, that cause minor irritations and may have long-term ill effects if they continue or are compounded by other stressful events.
  • Basilar membrane. A vibrating structure that runs through the center of the cochlea, dividing it into an upper chamber and a lower chamber and containing sense receptors for sound.
  • Behavior modification. A technique whose goal is to increase the frequency of desirable behaviors and decrease the incidence of unwanted ones.
  • Behavioral assessment. Direct measures of an individual's behavior used to describe personality characteristics.
  • Behavioral genetics. The study of the effects of heredity on behavior.
  • Behavioral neuroscientists (or biopsychologists). Psychologists who specialize in considering the ways in which the biological structures and functions of the body affect behavior.
  • Behavioral perspective. The approach that suggests that observable, external behavior, which can be objectively measured, should be the focus of study.
  • Behavioral treatment approaches. Treatment approaches that make use of the basic processes of learning, such as reinforcement and extinction, to reduce or eliminate maladaptive behavior.
  • Biofeedback. A procedure in which a person learns to control through conscious thought internal physiological processes such as blood pressure, heart and respiration rate, skin temperature, sweating, and the constriction of particular muscles.
  • Biological and evolutionary approaches to personality. Theories that suggest that important components of personality are inherited.
  • Biomedical therapy. Therapy that relies on drugs and other medical procedures to improve psychological functioning.
  • Bipolar disorder. A disorder in which a person alternates between periods of euphoric feelings of mania and periods of depression.
  • Bisexuals. Persons who are sexually attracted to people of the same sex and the other sex.
  • Borderline personality disorder. A disorder characterized by problems regulating emotions and thoughts, displaying impulsive and reckless behavior, and having unstable relationships with others.
  • Bottom-up processing. Perception that consists of the progression of recognizing and processing information from individual components of a stimuli and moving to the perception of the whole.
  • Bulimia. A disorder in which a person binges on large quantities of food, followed by efforts to purge the food through vomiting or other means.
  • Cannon-Bard theory of emotion. The belief that both physiological arousal and emotional experience are produced simultaneously by the same nerve stimulus.
  • Case study. An in-depth, intensive investigation of an individual or small group of people.
  • Cataclysmic events. Strong stressors that occur suddenly and typically affect many people at once (e.g., natural disasters).
  • Catharsis. The process of discharging built-up aggressive energy.
  • Central core. The "old brain," which controls basic functions such as eating and sleeping and is common to all vertebrates.
  • Central nervous system (CNS). The part of the nervous system that includes the brain and spinal cord.
  • Central route processing. The type of mental processing that occurs when a persuasive message is evaluated by thoughtful consideration of the issues and arguments used to persuade.
  • Central traits. The major traits considered in forming impressions of others.
  • Cerebellum (ser-uh-BELL-um). The part of the brain that controls bodily balance.
  • Cerebral cortex. The "new brain," responsible for the most sophisticated information processing in the brain; contains four lobes.
  • Chromosomes. Rod-shaped structures that contain all basic hereditary information.
  • Chunk. A group of familiar stimuli stored as a single unit in short-term memory.
  • Circadian rhythms. Biological processes that occur regularly on approximately a 24-hour cycle.
  • Classical conditioning. A type of learning in which a neutral stimulus comes to bring about a response after it is paired with a stimulus that naturally brings about that response.
  • Cochlea (KOKE-lee-uh). A coiled tube in the ear filled with fluid that vibrates in response to sound.
  • Cognitive approaches to motivation. Theories suggesting that motivation is a result of people's thoughts, beliefs, expectations, and goals.
  • Cognitive development. The process by which a child's understanding of the world changes due to the child's age and experience.
  • Cognitive dissonance. The mental conflict that occurs when a person holds two contradictory attitudes or thoughts (referred to as cognitions).
  • Cognitive learning theory. An approach to the study of learning that focuses on the thought processes that underlie learning.
  • Cognitive perspective. The approach that focuses on how people think, understand, and know about the world.
  • Cognitive psychology. The branch of psychology that focuses on the study of higher mental processes, including thinking, language, memory, problem solving, knowing, reasoning, judging, and decision making.
  • Cognitive treatment approaches. Treatment approaches that teach people to think in more adaptive ways by changing their dysfunctional cognitions about the world and themselves.
  • Collective unconscious. According to Jung, an inherited set of ideas, feelings, images, and symbols that are shared with all humans because of our common ancestral past.
  • Collectivism. An idea that the well-being of the group or society is more important than that of the individual.
  • Community psychology. A branch of psychology that focuses on the prevention and minimization of psychological disorders in the community.
  • Companionate love. The strong affection we have for those with whom our lives are deeply involved.
  • Compliance. Behavior that occurs in response to direct social pressure.
  • Compulsion. An irresistible urge to repeatedly carry out some act that seems strange and unreasonable.
  • Concept. A mental grouping of similar objects, events, or people.
  • Concrete operational stage. According to Piaget, the period from 7 to 12 years of age that is characterized by logical thought and a loss of egocentrism.
  • Conditioned response (CR). A response that, after conditioning, follows a previously neutral stimulus (e.g., salivation at the ringing of a bell).
  • Conditioned stimulus (CS). A once- neutral stimulus that has been paired with an unconditioned stimulus to bring about a response formerly caused only by the unconditioned stimulus.
  • Cones. Cone-shaped, light-sensitive receptor cells in the retina that are responsible for sharp focus and color perception, particularly in bright light.
  • Confirmation bias. The tendency to seek out and weight more heavily information that supports one's initial hypothesis and to ignore contradictory information that supports alternative hypotheses or solutions.
  • Conformity. A change in behavior or attitudes brought about by a desire to follow the beliefs or standards of other people.
  • Consciousness. The awareness of the sensations, thoughts, and feelings being experienced at a given moment.
  • Constructive processes. Processes in which memories are influenced by the meaning we give to events.
  • Continuous reinforcement schedule. A schedule in which behavior is reinforced every time the behavior occurs.
  • Control group. A group participating in an experiment that receives no treatment.
  • Convergent thinking. Thinking in which a problem is viewed as having a single answer and which produces responses that are based primarily on knowledge and logic.
  • Conversion disorder. A major somatic symptom disorder that involves an actual physical disturbance, such as the inability to use a sensory organ or the complete or partial inability to move an arm or leg.
  • Coping. The efforts to control, reduce, or learn to tolerate the threats that lead to stress.
  • Correlational research. Research in which the relationship between two sets of variables is examined to determine whether they are associated, or "correlated."
  • Creativity. The ability to generate original ideas or solve problems in novel ways.
  • Cross-cutting relations. The links between groups in the areas of work, education, and recreation.
  • Cross-sectional research. A research method that compares people of different ages at the same point in time.
  • Crystallized intelligence. The accumulation of information, knowledge, and skills that people have learned through experience and education.
  • Cue-dependent forgetting. Forgetting that occurs when there are insufficient retrieval cues to rekindle information that is in memory.
  • Culture. The learned behaviors, beliefs, and attitudes that characterize an individual society or population.
  • Culture-fair IQ test. A test trial that does not discriminate against the members of any minority group.
  • Daydreams. Fantasies that people construct while awake.
  • Decay. The loss of information in memory through its nonuse.
  • Declarative memory. Memory for factual information: names, faces, dates, and the like.
  • Defense mechanisms. In Freudian theory, unconscious strategies that people use to reduce anxiety by distorting reality and concealing the source of the anxiety from themselves.
  • Deinstitutionalization. The transfer of former mental patients from institutions to the community.
  • Dendrite. A cluster of fibers at one end of a neuron that receives messages from other neurons.
  • Dependent variable. The variable that is measured in an experiment. It is expected to change as a result of the experimenter's manipulation of the independent variable.
  • Depressants. Drugs that slow down the nervous system.
  • Depth perception. The ability to view the world in three dimensions and to perceive distance.
  • Determinism. The idea that people's behavior is produced primarily by factors outside of their willful control.
  • Developmental psychology. The branch of psychology that studies the patterns of growth and change that occur throughout life.
  • Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). A system, devised by the American Psychiatric Association, used by most professionals to classify and define psychological disorders.
  • Difference threshold (just noticeable difference). The smallest level of added or reduced stimulation required to sense that a change in stimulation has occurred.
  • Diffusion of responsibility. The belief that responsibility for intervening is shared, or diffused, among those present.
  • Discrimination. Behavior directed toward individuals on the basis of their membership in a particular group.
  • Disengagement theory of aging. The theory that suggests that successful aging is characterized by a gradual withdrawal from the world on physical, psychological, and social levels.
  • Dispositional causes (of behavior). Perceived causes of behavior brought about by a person's traits or personality characteristics.
  • Dissociative amnesia. A disorder in which a significant, selective memory loss occurs.
  • Dissociative disorders. Psychological dysfunctions characterized by the separation of different facets of a person's personality that are normally integrated.
  • Dissociative fugue. A form of amnesia in which a person leaves home and assumes a new identity.
  • Dissociative identity disorder (DID). A disorder in which a person displays characteristics of two or more distinct personalities.
  • Divergent thinking. Thinking that generates unusual, yet nonetheless appropriate, responses to problems or questions.
  • Double standard. The view that premarital sex is permissible for males but not for females.
  • Dreams-for-survival theory. The theory suggesting that dreams permit information that is critical for our daily survival to be reconsidered and reprocessed during sleep.
  • Drive. Motivational tension, or arousal, that energizes behavior to fulfill a need.
  • Drive-reduction approaches to motivation. Theories suggesting that a lack of some basic biological need produces a drive to push an organism to satisfy that need.
  • Drug therapy. Treatment of psychological disorders through the use of drugs.
  • Eardrum. The part of the ear that vibrates when sound waves hit it.
  • Ego. The part of personality that attempts to balance the desires of the id and the realities of the objective, outside world.
  • Ego-integrity-versus-despair stage. According to Erikson, a period from late adulthood until death during which we review life's accomplishments and failures.
  • Egocentric thought. A way of thinking in which a child views the world entirely from his or her own perspective.
  • Electroconvulsive therapy (ECT). A procedure used in the treatment of severe depression in which an electric current of 70-150 volts is briefly administered to a patient's head.
  • Embryo. A developed zygote that has a heart, a brain, and other organs.
  • Emerging adulthood. The period beginning in the late teenage years and extending into the mid-20s.
  • Emotional intelligence. The set of skills that underlie the accurate assessment, evaluation, expression, and regulation of emotions.
  • Emotions. Feelings that generally have both physiological and cognitive elements and that influence behavior.
  • Endocrine system. A chemical communication network that sends messages throughout the body via the bloodstream.
  • Episodic memory. Memory for events that occur in a particular time, place, or context.
  • Estrogens. Class of female sex hormones.
  • Ethnicity. Shared national origins or cultural patterns.
  • Evolutionary psychology. The branch of psychology that seeks to identify behavior patterns that are a result of our genetic inheritance from our ancestors.
  • Excitatory message. A chemical message that makes it more likely that a receiving neuron will fire and an action potential will travel down its axon.
  • Experiment. The investigation of the relationship between two (or more) variables by deliberately producing a change in one variable in a situation and observing the effects of that change on other aspects of the situation.
  • Experimental bias. Factors that distort how the independent variable affects the dependent variable in an experiment.
  • Experimental group. Any group participating in an experiment that receives a treatment.
  • Experimental manipulation. The change that an experimenter deliberately produces in a situation.
  • Explicit memory. Intentional or conscious recollection of information.
  • Extinction. A basic phenomenon of learning that occurs when a previously conditioned response decreases in frequency and eventually disappears.
  • Extramarital sex. Sexual activity between a married person and someone who is not his or her spouse.
  • Facial-affect program. Activation of a set of nerve impulses that make the face display the appropriate expression.
  • Facial-feedback hypothesis. The hypothesis that facial expressions not only reflect emotional experience but also help determine how people experience and label emotions.
  • Familial intellectual disability. Intellectual disability in which no apparent biological defect exists but there is a history of intellectual disability in the family.
  • Family therapy. An approach that focuses on the family and its dynamics.
  • Feature detector. Specialized neurons that are activated only by visual stimuli having specific features, such as a particular shape or pattern.
  • Fetal alcohol syndrome. The most common cause of intellectual disability in newborns, occurring when the mother uses alcohol during pregnancy.
  • Fetus. A developing individual from 8 weeks after conception until birth.
  • Fixations. Conflicts or concerns that persist beyond the developmental period in which they first occur.
  • Fixed-interval schedule. A schedule in which reinforcement is provided for a response only after a fixed time period has elapsed.
  • Fixed-ratio schedule. A schedule in which reinforcement is given only after a specific number of responses are made.
  • Flashbulb memories. Memories of a specific, important, or surprising emotionally significant event that are recalled easily and with vivid imagery.
  • Flooding. A behavioral treatment for anxiety in which people are suddenly confronted with a stimulus that they fear.
  • Fluid intelligence. Intelligence that reflects the ability to think logically, reason abstractly, and solve problems.
  • Formal operational stage. According to Piaget, the period from age 12 to adulthood that is characterized by abstract thought.
  • Free will. The idea that behavior is caused primarily by choices that are made freely by the individual.
  • Frequency theory of hearing. The theory that the entire basilar membrane acts like a microphone, vibrating as a whole in response to a sound.
  • Functional fixedness. The tendency to think of an object only in terms of its typical use.
  • Functionalism. An early approach to psychology that concentrated on what the mind does -- the functions of mental activity -- and the role of behavior in allowing people to adapt to their environments.
  • Fundamental attribution error. A tendency to overattribute others' behavior to dispositional causes and minimize the importance of situational causes.
  • G or g-factor. The single, general factor for mental ability assumed to underlie intelligence in some early theories of intelligence.
  • Gate-control theory of pain. The theory that particular nerve receptors in the spinal cord lead to specific areas of the brain related to pain.
  • General adaptation syndrome (GAS). A theory developed by Selye that suggests that a person's response to a stressor consists of three stages: alarm and mobilization, resistance, and exhaustion.
  • Generalized anxiety disorder. The experience of long-term, persistent anxiety and worry.
  • Generativity-versus-stagnation stage. According to Erikson, a period in middle adulthood during which we take stock of our contributions to family and society.
  • Genes. The parts of the chromosomes through which genetic information is transmitted.
  • Genetic preprogramming theories of aging. Theories that suggest that human cells have a built-in time limit to their reproduction and that they are no longer able to divide after a certain time.
  • Genital stage. According to Freud, the period from puberty until death, marked by mature sexual behavior (that is, sexual intercourse).
  • Genitals. The male and female sex organs.
  • Gestalt laws of organization (geh-SHTALLT). A series of principles that describe how we organize bits and pieces of information into meaningful wholes.
  • Gestalt psychology. An approach to psychology that focuses on the organization of perception and thinking in a "whole" sense rather than on the individual elements of perception.
  • Grammar. The system of rules that determine how our thoughts can be expressed.
  • Group. Two or more people who interact with one another, perceive themselves as part of a group, and are interdependent.
  • Group therapy. Therapy in which people meet in a group with a therapist to discuss problems.
  • Groupthink. A type of thinking in which group members share such a strong motivation to achieve consensus that they lose the ability to critically evaluate alternative points of view.
  • Habituation. The decrease in the response to a stimulus that occurs after repeated presentations of the same stimulus.
  • Hair cells. Tiny cells covering the basilar membrane that, when bent by vibrations entering the cochlea, transmit neural messages to the brain.
  • Hallucinogen. Drugs that are capable of producing alterations in perception, thoughts, and feelings.
  • Halo effect. A phenomenon in which an initial understanding that a person has positive or negative traits is used to infer other uniformly positive or negative characteristics.
  • Hardiness. A personality trait characterized by a sense of commitment, the perception of problems as challenges, and a sense of control.
  • Health psychology. The branch of psychology that investigates the psychological factors related to wellness and illness, including the prevention, diagnosis, and treatment of medical problems.
  • Hemispheres. Symmetrical left and right halves of the brain that control the side of the body opposite to their location.
  • Heritability. The degree to which a characteristic is related to genetic, inherited factors.
  • Heterosexuality. Sexual attraction and behavior directed to the other sex.
  • Heuristic. A thinking strategy that may lead us to a solution to a problem or decision but -- unlike algorithms -- may sometimes lead to errors.
  • Homeostasis. The body's tendency to maintain a steady internal state.
  • Homosexuals. Persons who are sexually attracted to members of their own sex.
  • Hormones. Chemicals that circulate through the blood and regulate the functioning or growth of the body.
  • Humanistic approaches to personality. Theories that emphasize people's innate goodness and desire to achieve higher levels of functioning.
  • Humanistic perspective. The approach that suggests that all individuals naturally strive to grow, develop, and be in control of their lives and behavior.
  • Humanistic therapy. Therapy in which the underlying rationale is that people have control of their behavior, can make choices about their lives, and are essentially responsible for solving their own problems.
  • Hypnosis. A trancelike state of heightened susceptibility to the suggestions of others.
  • Hypothalamus. A tiny part of the brain, located below the thalamus, that maintains homeostasis and produces and regulates vital behavior, such as eating, drinking, and sexual behavior.
  • Hypothesis. A prediction, stemming from a theory, stated in a way that allows it to be tested.
  • Id. The instinctual and unorganized part of personality whose sole purpose is to reduce tension created by primitive drives related to hunger, sex, aggression, and irrational impulses.
  • Identical twins. Twins who are genetically identical.
  • Identification. The process of wanting to be like another person as much as possible, imitating that person's behavior and adopting similar beliefs and values.
  • Identity. The distinguishing character of the individual: who each of us is, what our roles are, and what we are capable of.
  • Identity-versus-role-confusion stage. According to Erikson, a time in adolescence of major testing to determine one's unique qualities.
  • Illness anxiety disorder. A disorder in which people have a constant fear of illness and a preoccupation with their health.
  • Implicit memory. Memories of which people are not consciously aware but that can affect subsequent performance and behavior.
  • Incentive approaches to motivation. Theories suggesting that motivation stems from the desire to attain external rewards, known as incentives.
  • Independent (view of self). To view oneself as behaving independently, competing rather than cooperating with others.
  • Independent variable. The variable that is manipulated by an experimenter.
  • Individualism. The idea that holds as a primary value the personal identity, uniqueness, freedom, and worth of the individual person.
  • Industrial-organizational psychology (I/O psychology). The branch of psychology focusing on work- and job-related issues, including worker motivation, satisfaction, safety, and productivity.
  • Industry-versus-inferiority stage. According to Erikson, the last stage of childhood, during which children age 6 to 12 years may develop positive social interactions with others or may feel inadequate and become less sociable.
  • Information processing. The way in which people take in, use, and store information.
  • Informed consent. A document signed by participants affirming that they have been told the basic outlines of the study and are aware of what their participation will involve.
  • Inhibitory message. A chemical message that prevents or decreases the likelihood that a receiving neuron will fire.
  • Initiative-versus-guilt stage. According to Erikson, the period during which children ages 3 to 6 years experience conflict between independence of action and the sometimes negative results of that action.
  • Insight. A sudden awareness of the relationships among various elements that had previously appeared to be independent of one another.
  • Instinct approaches to motivation. Theories suggesting that motivation stems from the desire to attain external rewards, known as incentives.
  • Instincts. Inborn patterns of behavior that are biologically determined rather than learned.
  • Intellectual disability. A condition characterized by significant limitations both in intellectual functioning and in conceptual, social, and practical adaptive skills.
  • Intellectually gifted. The 2-4% segment of the population who have IQ scores greater than 130.
  • Intelligence. The capacity to understand the world, think rationally, and use resources effectively when faced with challenges.
  • Intelligence quotient (IQ). A score that takes into account an individual's mental and chronological ages.
  • Intelligence tests. Tests devised to quantify a person's level of intelligence.
  • Interactionist approach (to language development). The view that language development is produced through a combination of genetically determined predispositions and environmental circumstances that help teach language.
  • Interdependent (view of self). To view oneself as a member of a larger society, working together with others to achieve social harmony.
  • Interference. The phenomenon by which information in memory disrupts the recall of other information.
  • Interpersonal attraction (or close relationship). Positive feelings for others; liking and loving.
  • Interpersonal therapy (IPT). Short-term therapy that focuses on the context of current social relationships, helping patients to control their moods and emotions.
  • Intimacy-versus-isolation stage. According to Erikson, a period during early adulthood that focuses on developing close relationships.
  • Introspection. A procedure in which people are presented with a stimulus -- such as an image or sentence -- and asked to describe, in their own words and in as much detail as they can, what they were experiencing.
  • James-Lange theory of emotion. The belief that emotional experience is a reaction to bodily events occurring as a result of an external situation ("I feel sad because I am crying").
  • Korsakoff's syndrome. A disease that afflicts long-term alcoholics, leaving some abilities intact but including hallucinations and a tendency to repeat the same story.
  • Language. The communication of information through symbols arranged according to systematic rules.
  • Latency period. According to Freud, the period between the phallic stage and puberty during which children's sexual concerns are temporarily put aside.
  • Latent learning. Learning in which a new behavior is acquired but is not demonstrated until some incentive is provided for displaying it.
  • Lateralization. The dominance of one hemisphere of the brain in specific functions, such as language.
  • Learned helplessness. A state in which people conclude that unpleasant or aversive stimuli cannot be controlled -- a view of the world that becomes so ingrained that they cease trying to remedy the aversive circumstances even if they actually can exert some influence on the situation.
  • Learning. A relatively permanent change in behavior brought about by experience.
  • Learning-theory approach (to language development). The theory that language acquisition follows the principles of reinforcement and conditioning.
  • Levels-of-processing theory. The theory of memory that emphasizes the degree to which new material is mentally analyzed.
  • Life review. The process by which people examine and evaluate their lives.
  • Limbic system. The part of the brain that controls eating, aggression, and reproduction.
  • Linguistic-relativity hypothesis. The hypothesis that language shapes and may determine the way people perceive and understand the world.
  • Lobes. The four major sections of the cerebral cortex: frontal, parietal, temporal, and occipital.
  • Long-term memory. Memory that stores information on a relatively permanent basis, although it may be difficult to retrieve.
  • Longitudinal research. A research method that investigates behavior as participants get older.
  • Major depressive disorder. A severe form of depression that interferes with concentration, decision making, and sociability.
  • Mania. An extended state of intense, wild elation.
  • Masturbation. Sexual self-stimulation.
  • Means-ends analysis. Involves repeated tests for differences between the desired outcome and what currently exists.
  • Medical perspective. The perspective that suggests that when an individual displays symptoms of abnormal behavior, the root cause will be found in a physical examination of the individual, which may reveal a hormonal imbalance, a chemical deficiency, or a brain injury.
  • Meditation. A learned technique for refocusing attention that brings about an altered state of consciousness.
  • Memory. The process by which we encode, store, and retrieve information.
  • Menopause. The period during which women stop menstruating and are no longer fertile.
  • Mental age. The age for which a given level of performance is average or typical.
  • Mental images. Representations in the mind of an object or event.
  • Mental set. A framework for thinking about a problem based on our prior experience with similar problems.
  • Metabolism. The rate at which food is converted to energy and expended by the body.
  • Metacognition. An awareness and understanding of one's own cognitive processes.
  • Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). A widely used self-report test that identifies people with psychological difficulties and is employed to predict some everyday behaviors.
  • Mirror neurons. Specialized neurons that fire not only when a person enacts a particular behavior, but also when a person simply observes another individual carrying out the same behavior.
  • Mood disorder. A disturbance in emotional experience that is strong enough to intrude on everyday living.
  • Mood stabilizers. Drugs used to treat mood disorders characterized by intense mood swings, especially manic episodes in bipolar disorder.
  • Motivation. The factors that direct and energize the behavior of humans and other organisms.
  • Motor neurons (efferen neurons). Neurons that communicate information from the brain and nervous system to muscles and glands.
  • Motor area. The part of the cortex that is largely responsible for the body's voluntary movement.
  • Multiculturalism. The view that members of all cultures deserve equal respect and that their contributions to society should be recognized.
  • Myelin sheath. A protective coat of fat and protein that wraps around the axon.
  • Narcissistic personality disorder. A personality disturbance characterized by an exaggerated sense of self-importance.
  • Narcotics. Drugs that increase relaxation and relieve pain and anxiety.
  • Nativist approach (to language development). The theory that humans are biologically prewired to learn language at certain times and in particular ways.
  • Naturalistic observation. Research in which an investigator simply observes some naturally occurring behavior and does not make a change in the situation.
  • Nature-nurture issue. The issue of the degree to which environment and heredity influence behavior.
  • Need for achievement. A stable, learned characteristic in which a person obtains satisfaction by striving for and achieving challenging goals.
  • Need for affiliation. An interest in establishing and maintaining relationships with other people.
  • Need for power. A tendency to seek impact, control, or influence over others and to be seen as a powerful individual.
  • Negative reinforcer. An unpleasant stimulus whose removal leads to an increase in the probability that a preceding response will be repeated in the future.
  • Neo-Freudian psychoanalysts. Psychoanalysts who were trained in traditional Freudian theory but who later rejected some of its major points.
  • Neonate. A newborn child.
  • Neurons. Nerve cells, the basic elements of the nervous system.
  • Neuroplasticity. Changes in the brain that occur throughout the life span relating to the addition of new neurons, new interconnections between neurons, and the reorganization of information-processing areas.
  • Neuroscience perspective. The approach that views behavior from the perspective of the brain, the nervous system, and other biological functions.
  • Neurotransmitters. Chemicals that carry messages across the synapse to the dendrite (and sometimes the cell body) of a receiver neuron.
  • Neutral stimulus. A stimulus that, before conditioning, does not naturally bring about the response of interest.
  • Norms. Standards of test performance that permit the comparison of one person's score on a test with the scores of other individuals who have taken the same test.
  • Obedience. A change in behavior in response to the commands of others.
  • Obesity. Body weight that is more than 20% above the average weight for a person of a particular height.
  • Object permanence. The awareness that objects -- and people -- continue to exist even if they are out of sight.
  • Observational learning. Learning by observing the behavior of another person, or model.
  • Obsession. A persistent, unwanted thought or idea that keeps recurring.
  • Obsessive-compulsive disorder (OCD). A disorder characterized by obsessions or compulsions.
  • Oedipal conflict. A child's intense, sexual interest in his or her opposite-sex parent.
  • Operant conditioning. Learning in which a voluntary response is strengthened or weakened, depending on its favorable or unfavorable consequences.
  • Operational definition. The translation of a hypothesis into specific, testable procedures that can be measured and observed.
  • Opponent-process theory of color vision. The theory that receptor cells for color are linked in pairs, working in opposition to each other.
  • Optic nerve. A bundle of ganglion axons that carry visual information to the brain.
  • Oral stage. According to Freud, a stage from birth to age 12 to 18 months, in which an infant's center of pleasure is the mouth.
  • Overgeneralization. The phenomenon by which children overapply a language rule, thereby making linguistic errors.
  • Ovulation. The point at which an egg is released from the ovaries.
  • Panic disorder. Anxiety disorder that takes the form of panic attacks lasting from a few seconds to several hours.
  • Parasympathetic division. The part of the autonomic division of the nervous system that acts to calm the body after an emergency has ended.
  • Partial reinforcement schedule (or intermittent reinforcement schedule). Reinforcing of a behavior some but not all of the time.
  • Passionate love (or romantic love). A state of intense absorption in someone that includes intense physiological arousal, psychological interest, and caring for the needs of another.
  • Perception. The sorting out, interpretation, analysis, and integration of stimuli by the sense organs and brain.
  • Perceptual constancy. Our understanding that physical objects are unvarying and consistent even though sensory input about them may vary.
  • Peripheral nervous system. The part of the nervous system that includes the autonomic and somatic subdivisions; made up of neurons with long axons and dendrites, it branches out from the spinal cord and brain and reaches the extremities of the body.
  • Peripheral route processing. The type of mental processing that occurs when a persuasive message is evaluated on the basis of irrelevant or extraneous factors.
  • Permissive parents. Parents who give their children relaxed or inconsistent direction and, although they are warm, require little of them.
  • Person-centered therapy. Therapy in which the goal is to reach one's potential for self-actualization.
  • Personal stressors. Major life events, such as the death of a family member, that have immediate negative consequences that generally fade with time.
  • Personality. The pattern of enduring characteristics that produce consistency and individuality in a given person.
  • Personality disorder. A disorder characterized by a set of inflexible, maladaptive behavior patterns that keep a person from functioning appropriately in society.
  • Phallic stage. According to Freud, a period beginning around age 3 during which a child's pleasure focuses on the genitals.
  • Phonemes. The smallest units of speech.
  • Phonology. The study of the smallest units of speech, called phonemes.
  • Pituitary gland. The major component of the endocrine system, or "master gland," which secretes hormones that control growth and other parts of the endocrine system.
  • Place theory of hearing. The theory that different areas of the basilar membrane respond to different frequencies.
  • Placebo. A false treatment, such as a pill, "drug," or other substance, without any significant chemical properties or active ingredient.
  • Positive reinforcer. A stimulus added to the environment that brings about an increase in a preceding response.
  • Posttraumatic stress disorder (PTSD). A phenomenon in which victims of major catastrophes or strong personal stressors feel long-lasting effects that may include re-experiencing the event in vivid flashbacks or dreams.
  • Practical intelligence. According to Sternberg, intelligence related to overall success in living.
  • Prejudice. A negative (or positive) evaluation of a particular group and its members.
  • Preoperational stage. According to Piaget, the period from 2 to 7 years of age that is characterized by language development.
  • Priming. A phenomenon that occurs when exposure to a word or concept (called a prime) later makes it easier to recall information related to the prime.
  • Principle of conservation. The knowledge that quantity is unrelated to the arrangement and physical appearance of objects.
  • Proactive interference. Interference in which information learned earlier disrupts the recall of material learned later.
  • Procedural memory. Memory for skills and habits, such as riding a bike or hitting a baseball; sometimes referred to as nondeclarative memory.
  • Projective personality test. A test in which a person is shown an ambiguous stimulus and asked to describe it or tell a story about it.
  • Prosocial behavior. Helping behavior.
  • Prototypes. Typical, highly representative examples of a concept.
  • Prozac. A widely prescribed -- but still controversial -- antidepressant.
  • Psychoactive drugs. Drugs that influence a person's emotions, perceptions, and behavior.
  • Psychoanalysis. Freud's psychotherapy in which the goal is to release hidden thoughts and feelings from the unconscious part of our minds in order to reduce their power in controlling behavior.
  • Psychoanalytic perspective. The perspective that suggests that abnormal behavior stems from childhood conflicts over opposing wishes regarding sex and aggression.
  • Psychoanalytic theory. Freud's theory that unconscious forces act as determinants of personality.
  • Psychodynamic approaches to personality. Approaches that assume that personality is primarily unconscious and motivated by inner forces and conflicts about which people have little awareness.
  • Psychodynamic perspective. The approach based on the view that behavior is motivated by unconscious inner forces over which the individual has little control.
  • Psychodynamic therapy. Therapy that seeks to bring unresolved past conflicts and unacceptable impulses from the unconscious into the conscious, where patients may deal with the problems more effectively.
  • Psychological tests. Standard measures devised to assess behavior objectively; used by psychologists to help people make decisions about their lives and understand more about themselves.
  • Psychology. The scientific study of behavior and mental processes.
  • Psychoneuroimmunology (PNI). The study of the relationship among psychological factors, the immune system, and the brain.
  • Psychophysics. The study of the relationship between the physical aspects of stimuli and our psychological experience of them.
  • Psychophysiological disorders. Medical problems influenced by an interaction of psychological, emotional, and physical difficulties.
  • Psychosexual stages. Developmental periods that children pass through during which they encounter conflicts between the demands of society and their own sexual urges.
  • Psychosocial development. Development of individuals' interactions and understanding of each other and of their knowledge and understanding of themselves as members of society.
  • Psychosurgery. Brain surgery once used to reduce the symptoms of mental disorder but rarely used today.
  • Psychotherapy. Treatment in which a trained professional -- a therapist -- uses psychological techniques to help a person overcome psychological difficulties and disorders, resolve problems in living, or bring about personal growth.
  • Puberty. The period at which maturation of the sexual organs occurs, beginning at about age 11 or 12 for girls and 13 or 14 for boys.
  • Punishment. A stimulus that decreases the probability that a previous behavior will occur again.
  • Race. Generally refers to obvious physical differences that set one group apart from others.
  • Random assignment to condition. A procedure in which participants are assigned to different experimental groups or "conditions" on the basis of chance and chance alone.
  • Rapid eye movement sleep (REM sleep). Sleep occupying 20% of an adult's sleeping time, characterized by increased heart rate, blood pressure, and breathing rate; erections; eye movements; and the experience of dreaming.
  • Rational-emotive behavior therapy. A form of therapy that attempts to restructure a person's belief system into a more realistic, rational, and logical set of views by challenging dysfunctional beliefs that maintain irrational behavior.
  • Realistic conflict theory. The theory that conflict arises from direct competition over-valued, but limited, resources.
  • Recall. Memory task in which specific information must be retrieved.
  • Reciprocity-of-liking effect. A tendency to like those who like us.
  • Recognition. Memory task in which individuals are presented with a stimulus and asked whether they have been exposed to it in the past or to identify it from a list of alternatives.
  • Reflex. An automatic, involuntary response to an incoming stimulus.
  • Reflexes. Unlearned, involuntary responses that occur automatically in the presence of certain stimuli.
  • Rehearsal. The repetition of information that has entered short-term memory.
  • Reinforcement. The process by which a stimulus increases the probability that a preceding behavior will be repeated.
  • Reinforcer. Any stimulus that increases the probability that a preceding behavior will occur again.
  • Relative deprivation. The sense that one lacks a desired resource in comparison to another group, which is perceived to have more.
  • Reliability. The property by which tests measure consistently what they are trying to measure.
  • Replicated research. Research that is repeated, sometimes using other procedures, settings, and groups of participants, to increase confidence in prior findings.
  • Repression. The defense mechanism in which the ego pushes unacceptable or unpleasant thoughts and impulses out of consciousness but maintains them in the unconscious.
  • Resilience. The ability to withstand, overcome, and actually thrive after profound adversity.
  • Resting state. The state in which there is a negative electrical charge of about −70 millivolts within a neuron.
  • Reticular formation. The part of the brain extending from the medulla through the pons; it is related to changes in the level of arousal of the body.
  • Retina. The part of the eye that converts the electromagnetic energy of light to electrical impulses for transmission to the brain.
  • Retroactive interference. Interference in which material that was learned later disrupts the retrieval of information that was learned earlier.
  • Retrograde amnesia. Amnesia in which memory is lost for occurrences prior to a certain event, but not for new events.
  • Reuptake. The reabsorption of neurotransmitters by a terminal button.
  • Rods. Thin, cylindrical receptor cells in the retina that are highly sensitive to light.
  • Rorschach test. A test that involves showing a series of symmetrical visual stimuli to people who then are asked what the figures represent to them.
  • Schachter-Singer theory of emotion. The belief that emotions are determined jointly by a nonspecific kind of physiological arousal and its interpretation, based on environmental cues.
  • Schedules of reinforcement. Different patterns of frequency and timing of reinforcement following desired behavior.
  • Schemas. Organized bodies of information stored in memory that bias the way new information is interpreted, stored, and recalled.
  • Schizophrenia. A class of disorders in which severe distortion of reality occurs.
  • Scientific method. The approach through which psychologists systematically acquire knowledge and understanding about behavior and other phenomena of interest.
  • Self. The way in which we look inward and define ourselves as individuals.
  • Self-actualization. A state of self-fulfillment in which people realize their highest potential in their own unique way.
  • Self-efficacy. The belief that we can master a situation and produce positive outcomes.
  • Self-esteem. The component of personality that encompasses our positive and negative self-evaluations.
  • Self-report measures. A method of gathering data about people by asking them questions about their own behavior and traits.
  • Self-serving bias. The tendency to attribute personal success to personal factors (skill, ability, or effort) and to attribute failure to factors outside oneself.
  • Semantic memory. Memory for general knowledge and facts about the world, as well as memory for the rules of logic that are used to deduce other facts.
  • Semantic networks. Mental representations of clusters of interconnected information.
  • Semantics. The meaning of words and sentences.
  • Semicircular canals. Three tube-like structures of the inner ear containing fluid that sloshes through them when the head moves, signaling rotational or angular movement to the brain.
  • Sensation. The activation of the sense organs by a source of physical energy.
  • Sensorimotor stage. According to Piaget, the stage from birth to 2 years, during which a child has little competence in representing the environment by using images, language, or other symbols.
  • Sensory neurons (afferent neurons). Neurons that transmit information from the perimeter of the body to the nervous system and brain.
  • Sensory area. The site in the brain of the tissue that corresponds to each of the senses, with the degree of sensitivity related to the amount of tissue.
  • Sensory memory. The initial, momentary storage of information, lasting only an instant.
  • Shaping. The process of teaching a complex behavior by rewarding closer and closer approximations of the desired behavior.
  • Short-term memory. Memory that holds information for 15 to 25 seconds.
  • Significant outcome. Meaningful results that make it possible for researchers to feel confident that they have confirmed their hypotheses.
  • Situational causes (of behavior). Causes of behavior that are external to a person.
  • Skin senses. The senses of touch, pressure, temperature, and pain.
  • Social cognition. The cognitive processes by which people understand and make sense of others and themselves.
  • Social cognitive approaches to personality. Theories that emphasize the influence of a person's cognitions -- thoughts, feelings, expectations, and values -- as well as observation of others' behavior, in determining personality.
  • Social influence. The process by which social groups and individuals exert pressure on an individual, either deliberately or unintentionally.
  • Social neuroscience. The subfield of social psychology that seeks to identify the neurological basis of social behavior.
  • Social psychology. The scientific study of how people's thoughts, feelings, and actions are affected by others.
  • Social support. A mutual network of caring, interested others.
  • Social supporter. A group member whose dissenting views make non-conformity to the group easier.
  • Sociocultural perspective. The perspective that assumes that people's behavior -- both normal and abnormal -- is shaped by the kind of family group, society, and culture in which they live.
  • Somatic division. The part of the peripheral nervous system that specializes in the control of voluntary movements and the communication of information to and from the sense organs.
  • Somatic symptom disorders. Psychological difficulties that take on a physical (somatic) form, but for which there is no medical cause.
  • Sound. The movement of air molecules brought about by a source of vibration.
  • Specific phobia. Intense, irrational fears of specific objects or situations.
  • Spinal cord. A bundle of neurons that leaves the brain and runs down the length of the back and is the main means for transmitting messages between the brain and the body.
  • Spontaneous recovery. The reemergence of an extinguished conditioned response after a period of rest and with no further conditioning.
  • Spontaneous remission. Recovery without formal treatment.
  • Stage 1 sleep. The state of transition between wakefulness and sleep, characterized by relatively rapid, low-amplitude brain waves.
  • Stage 2 sleep. A sleep deeper than that of stage 1, characterized by a slower, more regular wave pattern, along with momentary interruptions of "sleep spindles."
  • Stage 3 sleep. A sleep characterized by slow brain waves, with greater peaks and valleys in the wave pattern than in stage 2 sleep.
  • Status. The social standing of someone in a group.
  • Stereotype. A set of generalized beliefs and expectations about a particular group and its members.
  • Stimulants. Drugs that have an arousal effect on the central nervous system, causing a rise in heart rate, blood pressure, and muscular tension.
  • Stimulus. Energy that produces a response in a sense organ.
  • Stimulus discrimination. The process that occurs if two stimuli are sufficiently distinct from one another that one evokes a conditioned response but the other does not; the ability to differentiate between stimuli.
  • Stimulus generalization. A process in which, after a stimulus has been conditioned to produce a particular response, stimuli that are similar to the original stimulus produce the same response.
  • Stress. A person's response to events that are threatening or challenging.
  • Structuralism. Wundt's approach, which focuses on uncovering the fundamental mental components of consciousness, thinking, and other kinds of mental states and activities.
  • Subjective well-being. People's sense of their happiness and satisfaction with their lives.
  • Superego. The part of personality that harshly judges the morality of our behavior.
  • Survey research. Research in which people chosen to represent a larger population are asked a series of questions about their behavior, thoughts, or attitudes.
  • Sympathetic division. The part of the autonomic division of the nervous system that acts to prepare the body for action in stressful situations, engaging all the organism's resources to respond to a threat.
  • Synapse. The space between two neurons where the axon of a sending neuron communicates with the dendrites of a receiving neuron by using chemical messages.
  • Syntax. Ways in which words and phrases can be combined to form sentences.
  • Systematic desensitization. A behavioral technique based on classical conditioning in which exposure to an anxiety-producing stimulus is paired with deep relaxation to extinguish the response of anxiety.
  • Telegraphic speech. Sentences in which only essential words are used.
  • Temperament. A basic, inborn characteristic way of responding and behavioral style.
  • Teratogens. Environmental agents such as drugs, chemicals, viruses, or other factors that produce birth defects.
  • Terminal buttons. Small bulges at the end of axons that send messages to other neurons.
  • Test standardization. A technique used to validate questions in personality tests by studying the responses of people with known diagnoses.
  • Thalamus. The part of the brain located in the middle of the central core that acts primarily to relay information about the senses.
  • Thematic Apperception Test (TAT). A test consisting of a series of pictures about which a person is asked to write a story.
  • Theories. Broad explanations and predictions concerning observations of interest.
  • Theory of multiple intelligences. Gardner's intelligence theory that proposes that there are eight distinct spheres of intelligence.
  • Thinking. Brain activity in which people mentally manipulate information, including words, visual images, sounds, or other data.
  • Tip-of-the-tongue phenomenon. The inability to recall information that one realizes one knows -- a result of the difficulty of retrieving information from long-term memory.
  • Top-down processing. Perception that is guided by higher-level knowledge, experience, expectations, and motivations.
  • Trait theory. A model of personality that seeks to identify the basic traits necessary to describe personality.
  • Traits. Consistent, habitual personality characteristics and behaviors that are displayed across different situations.
  • Transcranial magnetic stimulation (TMS). A depression treatment in which a precise magnetic pulse is directed to a specific area of the brain.
  • Transference. The transfer of feelings to a psychoanalyst of love or anger that had been originally directed to a patient's parents or other authority figures.
  • Transgender. An umbrella term for persons whose gender identity, gender expression, or behavior does not conform to that typically associated with the sex to which they were assigned at birth.
  • Treatment. The manipulation implemented by the experimenter.
  • Trichromatic theory of color vision. The theory that there are three kinds of cones in the retina, each of which responds primarily to a specific range of wavelengths.
  • Trust-versus-mistrust stage. According to Erikson, the first stage of psychosocial development, occurring from birth to age 1½ years, during which time infants develop feelings of trust or lack of trust.
  • Type A behavior pattern. A cluster of behaviors involving hostility, competitiveness, time urgency, and feeling driven.
  • Type B behavior pattern. A cluster of behaviors characterized by a patient, cooperative, noncompetitive, and nonaggressive manner.
  • Unconditional positive regard. An attitude of acceptance and respect on the part of an observer, no matter what a person says or does.
  • Unconditioned response (UCR). A response that is natural and needs no training (e.g., salivation at the smell of food).
  • Unconditioned stimulus (UCS). A stimulus that naturally brings about a particular response without having been learned.
  • Unconscious. A part of the personality that contains the memories, knowledge, beliefs, feelings, urges, drives, and instincts of which the individual is not aware.
  • Unconscious wish fulfillment theory. Sigmund Freud's theory that dreams represent unconscious wishes that dreamers desire to see fulfilled.
  • Uninvolved parents. Parents who show little interest in their children and are emotionally detached.
  • Validity. The property by which tests actually measure what they are supposed to measure.
  • Variable-interval schedule. A schedule by which the time between reinforcements varies around some average rather than being fixed.
  • Variable-ratio schedule. A schedule by which reinforcement occurs after a varying number of responses rather than after a fixed number.
  • Variables. Behaviors, events, or other characteristics that can change, or vary, in some way.
  • Visual illusions. Physical stimuli that consistently produce errors in perception.
  • Wear-and-tear theories of aging. Theories that suggest that the mechanical functions of the body simply stop working efficiently.
  • Weber's law. A basic law of psychophysics stating that a just noticeable difference is a constant proportion to the intensity of an initial stimulus (rather than a constant amount).
  • Weight set point. The particular level of weight that the body strives to maintain.
  • Working memory. A memory system that holds information temporarily while actively manipulating and rehearsing that information.
  • Zone of proximal development (ZPD). According to Vygotsky, the gap between what children already are able to accomplish on their own and what they are not quite ready to do by themselves.
  • Zygote. The new cell formed by the union of an egg and sperm.