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racism (1) an individual's prejudicial attitudes and discriminatory behavior toward people of a given race, or (2) institutional practices (even if not motivated by prejudice) that subordinate people of a given race.
radical behaviorism An approach usually associated with B. F. Skinner which asserts that the subject matter of psychology is overt behavior, without reference to inferred, internal processes such as wishes, traits, or expectations.
random assignment In experimental design, the random placement of participants in experimental versus control groups in order to insure that all groups are matched at the outset of the experiment.
Random assignment Placement of research participants into experimental conditions in a manner which guarantees that all have an equal chance of being exposed to each level of the independent variable.
random assignment the process of assigning participants to the conditions of an experiment such that all persons have the same chance of being in a given condition. (Note the distinction between random assignment in experiments and random sampling in surveys. Random assignment helps us infer cause and effect. Random sampling helps us generalize to a population.)
random sample survey procedure in which every person in the population being studied has an equal chance of inclusion. A sample in which each member of a population has an equal chance of being chosen as a subject.
range A measure of the variability contained in a set of scores, calculated by subtracting the lowest score from the highest.
Rape myth The false belief that deep down, women enjoy forcible sex and find it sexually exciting.
ratio scale An interval scale in which there is a true zero point, thus allowing statements about proportions (e.g., this sound is twice as loud as the other). See alsocategorical scale, interval scale, nominal scale, ordinal scale.
ratio schedule A reinforcement schedule in which reinforcement is delivered for the first response made after a certain number of responses. In a fixed-ratio schedule, the number of responses required for a reward is always the same. In a variable-ratio schedule, the number of responses required varies irregularly around a specified average.
rationalization In psychoanalytic theory, a mechanism of defense by means of which unacceptable thoughts or impulses are reinterpreted in more acceptable and, thus, less anxiety-arousing terms (e.g., the jilted lover who convinces herself that she never loved her fiancé anyway).
Raven's Progressive Matrices Test: an IQ test that gauges the subject's ability to solve problems that are presented in unfamiliar designs.
reactance (1) a motive to protect or restore one's sense of freedom. Reactance arises when someone threatens our freedom of action. (2) The desire to assert one's sense of freedom.
reaction formation In psychoanalytic theory, a mechanism of defense in which a forbidden impulse is turned into its opposite (e.g., hate toward a sibling becomes exaggerated love).
reaction time The interval between the presentation of a signal and the observer’s response to that signal.
Realistic conflict theory The theory that intergroup conflict develops from competition for limited resources.
realistic group conflict theory the theory that prejudice arises from competition between groups for scarce resources.
reality principle In Freud’s theory, the set of rules that govern the ego and that dictate the way in which it tries to satisfy the id by gaining pleasure in accordance with the real world and its demands.
reasoning The determination of the conclusions that can be drawn from certain premises.
recall A task in which some item must be produced from memory. See alsorecognition.
receiver-operating-characteristic curve (ROC curve) A graphical representation of the relationship between stimulus sensitivity and response bias.
recency effect In free recall, the tendency to recall items at the end of the list more readily than those in the middle. See alsoprimacy effect (in free recall). Information presented last sometimes has the most influence. Recency effects are less common than primacy effects.
Recency effect The tendency for the last information received to carry greater weight than earlier information.
receptive field The retinal area in which visual stimulation affects a particular cell’s firing rate.
receptive language: an understanding of the spoken and written word.
receptor cells A special type of neuron that can respond to various external energies and transduce (translate) physical stimuli into electrical changes to which other neurons can respond.
receptor molecules The specialized molecules in the postsynaptic membrane that open or close certain ion channels when activated by the correct neurotransmitter.
recessive geneSeegene.
reciprocal altruismSeealtruism.
Reciprocal helping (Also know as reciprocal altruism.) A sociobiological principle stating that people expect that anyone helping another will have that favor returned at some future time.
reciprocal inhibition The arrangement by which excitation of some neural system is accompanied by inhibition of that system’s antagonist (as in antagonistic muscles).
reciprocal interaction The fact that different people seek out different situations. See alsoperson-by-situation interaction, situationism.
reciprocity norm an expectation that people will help, not hurt, those who have helped them. The expectation that one should return a favor or good deed.
reciprocity principle A basic rule of many social interactions that decrees that one must repay whatever one has been given.
recoding Changing the form in which information is stored.
recognition A task in which a participant must judge whether he has encountered a stimulus previously. See alsorecall.
reconditioning In classical conditioning, the presentation of further reinforced conditioning trials (i.e., those that include the unconditioned stimulus [US]) after a conditioned response (CR) has been extinguished.
reductionistic perspective: studies human development by reducing complex phenomenon or events to a single cause.
Reference group A group to which people orient themselves, using its standards to judge themselves and the world.
reference The relations between words or sentences and objects or events in the world (e.g., the word ball refers to a ball, that spherical object used in games and sports).
reflectance The proportion of light aimed at an object that is reflected by it. An object’s reflectance determines whether the object is perceived as light or dark.
Reflected appraisal Perception of how others perceive us and evaluate us.
reflection The process by which objects give off light from a source of illumination.
reflex A simple, stereotyped reaction in response to some stimulus (e.g., limb flexion in withdrawal from pain). An involuntary action, as a sneeze, resulting from a stimulus that is carried by an afferent nerve to a nerve center and the response that is reflected along an efferent nerve to some muscle or gland.
refractory periods: the waiting time before men can regain an erection after they have ejaculated.
regression toward the average the statistical tendency for extreme scores or extreme behavior to return toward one's average.
rehearsalSeeelaborative rehearsal, maintenance rehearsal.
reinforced trial In classical conditioning, a trial on which the conditioned stimulus (CS) is followed by the unconditioned stimulus ( US ). In instrumental conditioning, a trial in which the instrumental response is followed by reward, cessation of punishment, or some other reinforcer.
reinforcement In classical conditioning, the procedure by which the unconditional stimulus (US) is presented contingent upon the occurrence of the conditioned stimulus (CS). In instrumental conditioning, the procedure by which a sought-after consequence is made contingent upon the occurrence of the instrumental response. Stimuli offered following a given behavior that increases the probability that the behavior will be repeated.
relational aggression A strategy for attaining social advantage by manipulating others’ social alliances. Females are apparently more relationally aggressive, whereas males are apparently more physically aggressive.
relative deprivation the perception that one is less well off than others to whom one compares oneself.
relative size A monocular depth cue in which far-off objects produce a smaller retinal image than nearby objects of the same size.
releasing stimulus A term used by ethologists to describe a stimulus that is genetically programmed to elicit a fixed-action pattern (e.g., a long, thin, red-tipped beak which elicits a herring gull chick’s begging response). See alsofixed-action patterns.
reliability coefficient The coefficient used in determining the consistency of mental tests, that is, the repeatability of their results. It is usually derived from test-retest correlations or from correlations between alternative forms of a test. See alsotest-retest method.
reliability The degree of consistency with which a test measures a trait or attribute. Assuming that a trait or attribute remains constant, a perfectly reliable test of that measure will produce the same score each time it is given.
reliable: that which can be relied on; dependable; trustworthy; in testing, provides consistent results when administered on different occasions.
REM rebound The tendency to spend more time in REM sleep if deprived of it on previous nights. REM rebound often occurs during withdrawal from medications that suppress REM sleep (e.g., barbiturates or alcohol).
REM sleep The type of sleep characterized by rapid eye movements, an EEG indicative of high cortical arousal, speeded heart rate and respiration, near-paralysis of limb muscles, and recall of highly visual dreams.
repetition priming An increase in the likelihood that an item will be identified, recognized, or recalled caused by recent exposure to that item, which may occur without explicit awareness.
replication A repetition of an experiment that yields the same results.
representational thought In Piaget’s theory, thought that is internalized and includes mental representations of prior experiences with objects and events. Symbolic thought, which children begin exhibiting around ages 18 to 24 months.
representations Cognitions that correspond to (represent) certain events, or relations between events, in the world.
representativeness heuristic A rule of thumb by means of which we estimate the probability that an object (or event) belongs to a certain category based on how prototypical it is of that category, regardless of how common it actually is. See alsoprototype. The tendency to judge the category membership of people based on how closely they match the "typical" or "average" member of that category. The tendency to presume, sometimes despite contrary odds, that someone or something belongs to a particular group if resembling (representing) a typical member.
repressed memory In psychoanalytic theory, a memory that is so anxiety-laden that it has been pushed out of consciousness where it may fester until it is "recovered." There is little scientific evidence for the existence of recoverable repressed memories.
repression In psychoanalytic theory, a mechanism of defense by means of which thoughts, impulses, or memories that give rise to anxiety are pushed out of consciousness. A conception developed initially by Freud and the psychoanalysts, which has largely displaced the dissociation (q.v.) of the French psychopathologists, the essential difference from 'dissociation' being its is dynamic and explanatory and not merely descriptive; applied primarily, with Freud, to a mental process arising from conflict between the 'pleasure principle' and the 'reality principle', as when impulses and desires are in conflict with enforced standards of conduct; as a result such impulses and desires with the associated memories and ideal systems, and the painful emotions arising out of the conflict, are actively or automatically thrust out of consciousness into the unconscious, in which, however, they still remain active, determining behavior and experience, for the most part indirectly and producing neurotic symptoms of various kinds, as well as determining dreams, both night and day, and underlying many types of deviations from normal behavior."
resistance In psychoanalysis, a term describing the patient’s failure to associate freely and say whatever enters her head.
response amplitude The size of a response, used commonly as a sign of response strength in classical and operant conditioning.
response bias In signal detection experiments, the willingness of the participant to assert that a stimulus has occurred or not occurred, given the costs of false positives or false negatives. See alsopayoff matrix.
response latency The time that elapses between an elicitor and a response (in classical conditioning, between the onset of a conditioned stimulus [CS] and the conditioned response [CR]). As classical conditioning proceeds, response latency usually decreases (i.e., the CR occurs sooner).
response rate The number of responses per unit of time. This is one measure of the strength of an operant response.
response suppression The inhibition of a response by conditioned fear.
response timeSeereaction time.
resting potential The difference in voltage across a neuronal membrane when the neuron is not firing.
restitutional symptoms For Eugen Bleuler, symptoms such as delusions and hallucinations that originated in the schizophrenic patient’s attempt to compensate for his increasing isolation from the world
restrained-eating hypothesis The hypothesis that obese persons are oversensitive to external food cues because their conscious restraints on eating have become disinhibited. See alsoexternality hypothesis, setpoint hypothesis.
restructuring A reorganization of a problem that can facilitate its solution; a characteristic of creative thought.
retention intervals In memory experiments, the time that elapses between the original learning and a later test.
retention The survival of a memory over some period of time.
retina The tissue-thin structure at the back of the interior of the eye that contains the photoreceptors, several layers of intermediate neurons, and the cell bodies of the axons that form the optic nerve.
retinal image The image of an object that is projected on the retina. Its size increases with the size of that object and decreases with the object’s distance from the eye.
retrieval cue A stimulus that helps one to recall a memory.
retrieval failure The inability to access a memory, often due to poor encoding; an alternative to erasure as an explanation for forgetting.
retrieval The process of searching for some item in memory and of finding it. If retrieval fails, this may or may not mean that the relevant memory trace is missing. The trace may simply be inaccessible.
retroactive inhibition The lessened ability to recall old material because of material learned subsequently. See alsoproactive inhibition.
retrograde amnesia A memory deficit, often suffered after a head injury, in which the patient loses memory of some period prior to the injury. See alsoanterograde amnesia.
reuptake A mechanism by which a neurotransmitter is vacuumed back into the presynaptic terminal that released it.
reversible figures Visual patterns that allow parsing such that what is initially figure becomes ground and vice versa (e.g., a drawing that can be seen as either a black picket fence against a white wall or a white picket fence against a black wall).
reward theory of attraction the theory that we like those whose behavior is rewarding to us or whom we associate with rewarding events.
Rh factor: incompatibility group of antigens, determined by heredity and usually present in human red blood cells, that may cause hemolytic reactions during pregnancy or after transfusion of blood containing this factor into someone lacking it.
rhodopsin The photopigment used in the rods within the retina.
risk aversion In decision making, the reluctance to choose an alternative that involves some risk.
rites of passage Ceremonies employed by cultures to mark important developmental transitions (e.g., puberty rites, debutante balls, graduation exercises).
RN - Registered Nurse
ROC curveSeereceiver-operating-characteristic curve.
rods Photoreceptors in the retina that respond to lower light intensities and give rise to achromatic (colorless) sensations.
role a set of norms that define how people in a given social position ought to behave.
role playing In psychotherapy, a technique in which the therapist and patient act out scenes, such as a marital confrontation, that are likely to occur outside the therapeutic situation.
romantic love A state of emotion characterized by idealization of the beloved, turbulent emotions, and obsessive thoughts. See alsocompanionate love.
Romeo-and-Juliet effect The intensification of romantic love that can occur with parental opposition.
rooting reflex In the infant, the sucking elicited by stroking applied on or around the lips; aids breast-feeding.
Rorschach inkblot test A projective (unstructured) technique of personality assessment that requires the examinee to look at a series of inkblots and report everything she sees in them.
rubella: a mild, infectious, communicable virus disease, characterized by swollen glands, especially of the back of the head and neck, and small red spots on the skin; German measles.
safety signal A cue which predicts that an aversive stimulus will not occur. See alsocontingency.
sample A subset of a population selected by the investigator for study. A random sample is constructed such that each member of the population has an equal chance of being picked. A stratified sample is constructed such that every relevant subgroup of the population is randomly sampled in proportion to its size. See alsopopulation. A selected segment of a population studied to gain knowledge of the whole.
saturation A perceived dimension of visual stimuli that describes the "strength" of a color — the extent to which it appears rich or pale (e.g., light pink vs. hot pink).
savant A mentally retarded person who has some remarkable talent that seems out of keeping with his low level of general intelligence. Previously idiot savant, a term now abandoned as derogatory.
scaling A procedure for assigning numbers to a subject’s responses. See alsocategorical scale, interval scale, nominal scale, ordinal scale, ratio scale.
scatter plot A graph depicting the relationship between two interval- or ratio-scale variables, with each axis representing one variable; often used to graph correlation data.
schedule of reinforcement The pattern of occasions on which responses are to be reinforced. Commonly, reinforcement is scheduled after a stipulated number of responses occurs or when a response occurs after a preset time interval has elpased. See alsoratio schedule, interval schedules.
Schemas Organized systems of beliefs about some stimulus object, which are built up from experience and which selectively guide the processing of new information. Piaget's term for innate thinking processes. In theories of memory and thinking, a term that refers to a general cognitive structure in which information is organized
schizophrenia A group of severe mental disorders characterized by at least some of the following: marked disturbance of thought, withdrawal, inappropriate or flat emotions, delusions, and hallucinations. See also catatonic schizophrenia, disorganized type of schizophrenia, negative symptoms of schizophrenia, paranoid schizophrenia, positive symptoms of schizophrenia.
scientific method: a systematic approach to researching questions and problems through objective and accurate observation, collection and analysis of data, direct experimentation, and replication of these procedures.
score profileSeetest profile.
script A subcase of a schema that describes a characteristic pattern of behavior in a particular setting, such as a restaurant. See alsoschema.
seasonal affective disorder A mood disorder that shows reliable fluctuations with the time of year. One example is a depression that ensues in the fall when the days become shorter and ends in the spring when the days lengthen.
second messengers Neurochemicals within the neuron that regulate such mechanisms as the creation of receptors sites for specific neurotransmitters and the synthesis of the neuron’s own neurotransmitter, thus determining the neuron’s overall responsiveness.
secondary memorySeelong-term memory.
secondary sexual characteristic: any of the physical characteristics that differentiate male and female individuals, as distribution of hair or fat on the body, breast and muscle development, deepening of the voice, and so on, that are not directly related to reproduction and usually appear at puberty.
second-order conditioningSeehigher-order conditioning.
Secure attachment style An expectation about social relationships characterized by trust, a lack of concern with being abandoned, and a feeling of being valued and well liked.
selective attention: the ability to focus or concentrate closely on something.
selective serotonin reuptake inhibitors (SSRIs) Medications such as Prozac, Zoloft, and Paxil that increase serotonin turnover in the brain and find wide use as treatments for depression, obsessive-compulsive disorder, panic disorder, and many other disorders.
Self A symbol-using individual who can reflect upon his/her own behavior.
self-actualization According to Abraham Maslow and some other adherents of the humanistic approach to personality, the full realization of one’s potential. See alsohierarchy of needs, peak experience.
Self-affirmation theory A theory predicting that people will often cope with specific threats to their self-esteem by reminding themselves of other unrelated but cherished aspects of their self-concept.
Self-awareness A psychological state in which one takes oneself as an object of attention. A self-conscious state in which attention focuses on oneself. It makes people more sensitive to their own attitudes and dispositions.
self-concept a person's answers to the question "Who am I?". Generally, the sum of one’s beliefs about and attitudes toward oneself. For Carl Rogers, the sense of oneself as both agent and object. The sum total of a person's thoughts and feelings that defines the self as an object. One's conception of oneself and one's own identity, abilities, worth, and so on.
Self-consciousness The habitual tendency to engage in self-awareness.
self-control The ability to pursue a goal while adequately managing internal conflicts about it.
self-disclosure revealing intimate aspects of oneself to others. The act of revealing personal information; usually occurs reciprocally and facilitates intimacy. The revealing of personal information about oneself to other people.
Self-discrepancy theory A theory that people experience specific negative emotions when they perceive a discrepancy between their self-concept and various self-guides.
self-efficacy a sense that one is competent and effective, distinguished from self-esteem, one's sense of self-worth. A bombardier might feel high self-efficacy and low self-esteem. A theory that motivation is determined both by the belief that one is capable of successfully performing some behavior, and by the belief that performing the behavior will lead to certain outcomes.
Self-enhancement The process of seeking out and interpreting situations so as to attain a positive view of oneself.
Self-Esteem"When the varying self images become organized into a more cohesive affective picture of the self, we speak of self-esteem, with 'high self-esteem' implying a predominance of pleasurable affect and 'low self-esteem' of unpleasurable ones. All of these ego states of affect-self-representation linkages may be either conscious, preconscious, or unconscious, have complex origins, and many defensive and adaptive functions". A person's evaluation of his or her self-concept. A person's overall self-evaluation or sense of self worth, belief in oneself; self-respect.
Self-evaluation maintenance model A theory predicting under what conditions people are likely to react to the success of others with either pride or jealousy.
Self-fulfilling prophecy The process by which someone's expectations about a person or group leads to the fulfillment of those expectations.
self-handicapping A self-protective strategy in which one arranges for an obvious, and nonthreatening obstacle to one’s own performance, such that any failure can be attributed to the obstacle and not to one’s own limitations. Actions that people take to sabotage their performance and enhance their opportunity to excuse anticipated failure. Protecting one's self-image with behaviors that create a handy excuse for later failure.
self-monitoring being attuned to the way one presents oneself in social situations and adjusting one's performance to create the desired impression. The process of making sure that one’s own behavior conforms with the demands of the current social situation. At the extremes, high self-monitors are pliant social chameleons, and low self-monitors are rigid and unaccommodating. The tendency to use cues from other people's self-presentations in controlling one's own self-presentations.
self-perception theory The theory that we know our own attitudes and feelings only indirectly, by observing our own behavior and then performing much the same processes of attribution that we employ when trying to understand others. The theory that we often infer our internal states, such as our attitudes, by observing our behavior. The theory that when we are unsure of our attitudes, we infer them much as would someone observing us, by looking at our behavior and the circumstances under which it occurs.
self-presentation the act of expressing oneself and behaving in ways designed to create a favorable impression or an impression that corresponds to one's ideals.
Self-promotion Conveying positive information about the self either through one's behavior or by telling others about one's positive assets and accomplishments.
self-reference effect the tendency to process efficiently and remember well information related to oneself.
self-regulatory systems For Walter Mischel, ways that individuals regulate their own behavior using self-imposed goals and plans.
self-reported data Data supplied by the research participant (usually, ratings of attitudes or moods, or tallies of behavior), rather than that collected by the experimenter.
self-schema beliefs about self that organize and guide the processing of self-relevant information.
Self-schemas The many beliefs people have about themselves that constitute the "ingredients" of the self-concept.
self-serving attributional bias The tendency, found largely in individualistic cultures, to deny responsibility for failures but take credit for successes. See alsoactor-observer difference, attribution theory, fundamental attribution error.
Self-serving bias The tendency to assign an internal locus of causality for our positive outcomes and an external locus for our negative outcomes. The tendency to perceive oneself favorably.
Self-verification The process of seeking out and interpreting situations so as to confirm one's self-concept
Sex The biological status of being male or female.
semantic feature The smallest significant unit of meaning within a word (e.g., male, human, and adult are semantic features of the word man).
semantic memory The component of generic memory that concerns the meaning of words and concepts.
semantic priming The enhanced performance on verbal tasks that occurs when the items being considered have similar meanings.
semantics The organization of meaning in language.
semicircular canals The three curved tubules found within the inner ear that contain a viscous liquid that is easily perturbed if jostled. The canals provide moment-to-moment information about head movements.
senile: showing the marked deterioration often accompanying old age, especially mental impairment characterized by confusion, memory loss, and so on.
sensation According to the empiricists, the primitive experiences that emanate from the senses (e.g., greenness, bitterness). The power or process of receiving conscious sense impressions through direct stimulation of the bodily organism; an immediate reaction to external stimulation of a sense organ; conscious feeling or sense impression.
sensation seeking A predisposition to seek novel experiences, look for thrills and adventure, and be highly susceptible to boredom.
sensation:sensitive periodSeecritical period.
sensorimotor stage: according to Piaget, from birth to age 2, infants and toddlers learn by doing: looking, hearing, touching, grasping, and sucking.
sensorimotor: of or pertaining to motor responses initiated by sensory stimulation.
sensory adaptation The decline in sensitivity found in most sensory systems after continuous exposure to the same stimulus.
sensory code The rule by which the nervous system represents the sensory characteristics of the stimulus. One example is firing frequency which, in touch and vision, encodes increased stimulus intensity. The process by which the sensory organs translate various stimulus qualities into the dimensions of our sensory experience.
sensory interaction The increased or decreased sensitivity of the sensory system in response to other ongoing stimulation.
sensory memory: a form of memory in which information is retained for less than 1 second.
sensory modalities A technical term for the sensory domains: taste, touch, smell, kinesthesis, vision, and hearing.
sensory neurons Neurons that convey information from sense organs to other portions of the nervous system.
sensory organs: specialized structures of the body containing sensory receptors that receive stimuli from the environment.
sensory process According to signal detection theorists, the underlying neural activity in the sensory system upon which all psychological judgments are based. See alsosignal-detection theory.
sensory projection areasSeeprimary projection areas.
sensory quality A distinguishing attribute of a stimulus (e.g., sound frequency as the determinant of pitch).
sensory receptors: convert environmental energy into nervous-system signals that the brain can understand and interpret.
sensory-motor intelligence In Piaget’s theory, intelligence during the first two years of life, consisting mainly of sensations and motor impulses, with little in the way of internalized representations.
sentence analyzing machinery (SAM) The sequence of strategies that listeners use to comprehend sentences.
separation anxiety The protest and distress exhibited by a child at the departure of a caretaker. Distress at the prospect of being left alone in an unfamiliar place or being separated from a familiar person.
serial ordering: the ability to group according to logical progression.
serial reproduction An experimental technique in which a drawing is presented to one research participant, who reproduces it from memory for a second participant, whose reproduction is shown to a third, and so on. Each participant’s memory distortions become part of the stimulus for the next participant down the line, such that reconstructive alterations accumulate.
serial search The successive comparison of a target stimulus to different items in memory. See alsoparallel search.
serotonin (5HT) A neurotransmitter involved in many of the mechanisms of sleep, arousal, aggression, and mood.
servomechanisms Devices that use negative feedback to maintain a stable state of affairs, such as a heating system that maintains a home at a constant temperature.
setSeemental set.
setpoint A general term for the level at which negative feedback tries to maintain stability. An example is the setting of a thermostat. See alsosetpoint hypothesis.
setpoint hypothesis The hypothesis that different persons have different setpoints for weight, such that attempts to alter one’s weight are physiologically countered and, thus, will ultimately prove ineffectual. See alsosetpoint.
settling down: a stage in the culminating phase of early adulthood, ranging from ages 33 to 40.
Sex differences Biologically based differences between males and females.
sex role: the quality of being male or female, based on anatomy.
sexism (1) an individual's prejudicial attitudes and discriminatory behavior toward people of a given sex, or (2) institutional practices (even if not motivated by prejudice) that subordinate people of a given sex.
Sexism Any attitude, action or institutional structure that subordinates a person because of his or her sex.
sexual dimorphism The state of affairs, observed in many species, in which the sexes differ in form (such as deer antlers or peacock tail feathers) or size. Sexual dimorphism is minimal among monogamous animals and maximal among polygamous ones.
Sexual harassment Unwelcome physical or verbal sexual overtures that create an intimidating, hostile, or offensive social environment.
sexual identity The sense of being male or female and all that goes with it, including issues of gender identity, gender role, and sexual orientation.
sexual latency: inactive sexual interest.
sexual orientation A person’s predisposition to choose members of the same or the opposite sex as romantic and sexual partners. See alsobisexuality, heterosexuality, and homosexuality.
Sexual orientation One's sexual attraction toward members of either one's own sex of the other sex. An individual's sexual, emotional, romantic, and affectionate attraction to members of the same sex, the other sex, or both.
shadowing The procedure, often used in dichotic presentations, in which a participant is asked to repeat aloud, word for word, only what she hears through one earphone.
shallow processing The encoding of a stimulus using its superficial characteristics, such as the way a word sounds or the typeface in which it is printed.
shape constancy The tendency to perceive objects as retaining their shapes despite changes in our angle of regard that produce changes in the image projected on the retina.
shaping An instrumental learning procedure in which an animal (or human) learns a rather difficult response through the reinforcement of successive approximations to that response. See alsosuccessive approximations.
short-term habituationSeehabituation.
short-term memory: a form of memory in which information is retained for less than 30 seconds.
signal-detection theory The theory that the act of perceiving or not perceiving a stimulus is actually a judgment about whether a momentary sensory experience is due to background noise alone or to the background noise plus a signal. See alsosensory process.
signs In psychopathology, what the diagnostician observes about a patient’s physical or mental condition (e.g., tremor, inattentiveness). See alsosymptoms, syndrome.
similarity In perception, a principle by which we tend to group like figures, especially by color and orientation.
simple cells Neurons in the visual cortex that respond to simple stimulus features such as orientation or position.
simple reaction time A measurement of the speed with which a research participant can respond to a stimulus.
simple reflex A sensorimotor reflex free of modulation by higher-level influences; approximated by Sir Charles Sherrington, who used spinal animals.
simulation heuristic A mental shortcut used in making decisions and evaluating outcomes that employs the imaginary replay of events or situations.
simultaneous color contrast The effect produced by the fact that any region in the visual field tends to induce its complementary color in adjoining areas. For example, a gray patch will tend to look bluish if surrounded by yellow and yellowish if surrounded by blue.
simultaneous pairing A classical conditioning procedure in which the conditioned stimulus (CS) and the unconditioned stimulus (US) are presented at the same time. See alsobackward pairing, forward pairing.
sine waves Waves that correspond to the plot of the trigonometric sine function.
single-case experiment A study in which the investigator manipulates the values of some independent variable, just as she would in an experiment with many participants, and then assesses the effects of this variable by recording the single participant’s responses. See alsocase study.
situational factorsSeeattribution theory.
situationism The view that human behavior is largely determined by the characteristics of the situation rather than personal predispositions. See alsobehavioral-cognitive approach, humanistic approach, psychodynamic approach, sociocultural approach, trait theory.
size and shape constancy: the consistent size and shape of objects.
size constancy The tendency to perceive objects as retaining their size, despite the increase or decrease in the size of the image projected on the retina caused by moving closer to or farther from the objects.
skeletal musculature The muscles (sometimes called striated muscles) that are controlled by parts of the somatic nervous system and that move the face, trunk, and limbs.
skewed A term used to describe distributions of experimental results that are asymmetrical (tending to have outlying values at one end).
sleep paralysis The phenomenon of waking up unable to move for several seconds, due to the persistence of the loss of muscle tone that occurs during REM sleep. While sleep paralysis is sometimes frightening, it is harmless.
sleeper effect a delayed impact of a message. Occurs when an initially discounted message becomes effective, as we remember the message but forget the reason for discounting it.
Sleeper effect The delayed effectiveness of a persuasive message from a noncredible source.
slow-wave sleep Type of sleep characterized by slow, rolling eye movements, an EEG indicative of low cortical arousal, slowed heart rate and respiration, and recall of "boring," mostly verbal dreams.
smooth muscles The nonstriated muscles controlled by the autonomic nervous system that constrict the blood vessels to help regulate blood pressure and that line many internal organs such as those that produce peristalsis in the digestive tract.
Social anxiety The unpleasant emotion people experience due to their concern with interpersonal evaluation.
Social categorization The classification of people into groups based on their common attributes.
social cognition The way in which we interpret and try to comprehend social events. experiential knowledge and understanding of society and the rules of social behavior.
social comparison A process of reducing uncertainty about one’s own beliefs and attitudes by comparing them to those of others, evaluating one's abilities and opinions by comparing oneself to others.
Social comparison theory The theory that proposes that we evaluate our thoughts and actions by comparing them to those of others.
Social constructionism A perspective in the social sciences that states that individuals creatively shape reality through social interaction.
social deprivation: the absence of attachment.
social development A child’s growth in his or her relations with other people.
social dilemma A problem similar in structure to the prisoner’s dilemma but expanded to include any number of individuals, each of whom has to decide whether to cooperate or act individually. See alsoprisoner’s dilemma. Any situation in which the most rewarding short-term choice for an individual will ultimately cause negative consequences for the group as a whole.
social exchange theory A theory that asserts that each partner in a social relationship gives something to the other and expects to get something in return. The theory that proposes that we seek out and maintain those relationships in which the rewards exceed the costs.
social facilitation (1) original meaning-the tendency of people to perform simple or well-learned tasks better when others are present (2) current meaning-strengthening of dominant (prevalent, likely) responses owing to the presence of others. The enhancement of dominant responses due to the presence of others. The tendency to perform better in the presence of others than when alone. This facilitating effect works primarily for simple or well-practiced tasks.
Social identities Aspects of a person's self-concept based upon his or her group memberships, the "we" aspect of our self-concept. The part of our answer to "Who am I?" that comes from our group memberships. Examples: "I am Australian." "I am Catholic."
Social impact theory The theory that the amount of social influence others have depends on their number, strength, and immediacy to those they are trying to influence. The theory that the influence others exert on an individual increases with their number, their immediacy, and their strength (e.g., status).
social inferences: assumptions about the nature of social relationships, processes, and others' feelings. A general term for interactions in which an individual’s thinking or behavior is affected by the actions of several others. The exercise of social power by a person or group to change the attitudes or behavior of others in a particular direction.
social intimacy: having the same friends and enjoying the same types of recreation.
social learning theory A theoretical approach to socialization and personality that is midway between radical behaviorism and cognitive approaches to learning. It stresses learning by observing others who serve as models and who show the child whether a response he already knows should or should not be performed. A theory that proposes that social behavior is primarily learned by observing and imitating the actions of others, and secondarily by being directly rewarded and punished for our own actions, the theory that we learn social behavior by observing and imitating and by being rewarded and punished.
social loafing An example of the diffusion of social impact in which people working collectively on a task generate less total effort than they would had they worked alone. Group-induced reduction in individual output when performer's efforts are pooled, and thus, cannot be individually judged. the tendency for people to exert less effort when they pool their efforts toward a common goal than when they are individually accountable.
Social penetration theory A theory that describes the development of close relationships in terms of increasing self-disclosure.
Social perception The way we seek to know and understand other persons and events.
social phobia A fear of embarrassment or humiliation that causes people to avoid situations that might expose them to public scrutiny. See alsoanxiety disorders, phobia, specific phobia.
Social physique anxiety Anxiety about others observing and evaluating one's physique.
Social power The force available to the influencer to motivate attitude or behavior change.
Social psychology The scientific discipline that attempts to understand and explain how the thought, feeling, and behavior of individuals are influenced by the actual, imagined, or implied presence of others.
social psychology the scientific study of how people think about, influence, and relate to one another.
social reality testing The normal process of validating one’s beliefs against others. This process is often disrupted in schizophrenia.
social representations socially shared beliefs, and widely held ideas and values, including our assumptions and cultural ideologies. Our social representations help us make sense of our world.
Social role theory The theory that virtually all of the documented behavioral differences between males and females can be accounted for in terms of cultural stereotypes about gender and the resulting social roles that are taught to the young.
Social roles A cluster of socially defined expectations that individuals in a give situation are expected to fulfill.
Social skills training A behavioral training program designed to improve interpersonal skills through observation, modeling, role-playing, and behavioral rehearsal.
social-exchange theory the theory that human interactions are transactions that aim to maximize one's rewards and minimize one's costs.
socialization The process whereby the child acquires the patterns of behavior characteristic of his or her society.
socializing agents: those influences that teach and reinforce society's rules and norms.
social-responsibility norm an expectation that people will help those dependent upon them.
Sociobiology A scientific discipline concerned with identifying biological and genetic bases for social behavior in humans and other animals.
sociocultural approach Within social psychology and personality psychology, the view that many psychological phenomena, some of which have been presumed to be universal, result from or are affected substantially by cultural norms.
sociopathySee antisocial personality disorder.
somatic nervous system A division of the peripheral nervous system primarily concerned with the control of the skeletal musculature and the transmission of information from the sense organs.
somatic therapies A collective term for any treatment of mental disorders by some organic means, including medication, surgery, and electroconvulsive therapy.
somatization disorder A mental disorder in which the patient reports miscellaneous aches and pains in various bodily systems that do not add up to any known syndrome in physical medicine.
somatoform disorders The generic term for mental disorders in which bodily symptoms predominate despite the absence of any known physical cause; included are conversion disorder, hypochondriasis, somatization disorder, and somatoform pain disorder.
somatoform pain disorder A mental disorder in which the sufferer describes chronic pain for which there is no discernible physical basis.
somatogenic hypothesis The hypothesis that mental disorders result from organic (bodily) causes.
somatogenic mental disorders Mental disorders that have known organic causes. This is the case for some disorders (e.g., general paresis) but almost surely not for all (e.g., phobias). See alsopsychogenic disorders.
somatosensory areaSeeprimary somatosensory projection area.
sound waves Successive pressure variations in the air that vary in amplitude and wavelength.
source confusion A type of memory error in which information acquired in one context is remembered as having been encountered in another (e.g., a person’s recalling that she had chocolate cake on her last birthday when she actually had it two birthdays ago).
source memory The knowledge of the event from which a certain memory derived.
spatial summation The process whereby two or more stimuli that are individually below threshold will elicit a reflex if they occur simultaneously at different points on the body.
spatial thinking The mental computations engaged in when we must locate objects and discern the spatial relationships among them.
Spearman’s theory of general intelligence (g) Spearman’s account, based on factor analytic studies of intelligence-test performance, which proposes one underlying factor, general intelligence (g), which is tapped by all subtests, and a large number of specific skills (s’s) that are tapped by each subtest. See alsofactor analysis, group-factor theory of intelligence.
species-specific behavior Behavior patterns characteristic of a species that are typically built-in and emerge without any relevant prior experience.
species-specific defense reaction Reactions to threat that are largely innate and found in all members of a species, e.g., flight in birds, "playing dead" in opossums.
specific language impairment An inherited syndrome that impairs language learning and causes lifelong deficits in sentence comprehension and production, despite otherwise normal cognitive functioning.
specific phobia A disabling, irrational fear of certain objects or events such as snakes, heights, or enclosed places. See alsoanxiety disorders, phobia.
specificity theory An approach to sensory experience which asserts that different sensory qualities are signaled by different neurons. These neurons are somehow labeled with their quality, so that whenever they fire, the nervous system interprets their activation as that particular sensory quality.
spectral sensitivity curve A graphical representation of the eye’s spectral sensitivity.
spectral sensitivity The eye’s responsiveness to each of the separate wavelengths that constitute a light stimulus.
speech plans Coordinated patterns of speech movements, constructed in Broca’s area, that are relayed to the primary motor projection area for decoding into discrete muscular movements.
sperm (spermatozoom) A sex cell manufactured in the testes and contributed by the male as part of sexual reproduction.
spinal animal An animal whose spinal cord has been severed in the neck region in order to cut all connections between the body (from the neck down) and the brain, leaving the spinal reflexes free of higher influences.
split brain A condition in which the corpus callosum and some other fibers are cut so that the two cerebral hemispheres are functionally isolated.
spontaneous recovery The reappearance of a previously extinguished response after a time interval in which neither the conditioned stimulus (CS) nor the unconditioned stimulus (US) is presented.
spreading activation model A memory model that assumes that elements in a semantic memory network are more heavily activated the closer they are to each other within the network.
stabilized image technique A procedure that projects a stationary image on the retina even though the eye is moving.
stable identity: the concept that one's self remains consistent even when circumstances change.
stage theories of development: theories that suggest that people go through a series of discrete stages, each of which is characterized by at least one task that an individual must accomplish before progressing to the next stage.
stage theory of memory An approach to memory that proposes several memory stores. One is short-term memory, which holds a small amount of information for fairly short intervals; another is long-term memory, which can hold vast amounts of information for extended periods. According to the theory, information can only be transferred to long-term memory if it has first been in short-term memory.
stagnation: a state of self-absorption, self-indulgence, and invalidism that middle adults may experience if they fail to develop generativity.
standard deviation (SD) A measure of the variability of a frequency distribution, calculated as the square root of the variance (V) — SD = .
standard error of the mean A measure of the variability of the mean whose value depends both on the standard deviation (SD) of the distribution and the number of cases in the sample (N); if SE is the standard error, then SE = SD/.
standard score (z-score) A score that is expressed as a deviation from the mean in standard deviations (SDs), which allows a comparison of scores drawn from different distributions; if M is the mean, then z = (score - M)/SD.
standardization group The group against which an individual’s test score is evaluated.
Stanford-Binet Intelligence Scale: a popular IQ test.
state: a set of circumstances or attributes characterizing a person or thing at a given time; way or form of being; condition.
statistical reliability The degree to which an observed difference in sample means reflects a real difference in population means and is not attributable to chance.
statistics The process of quantitatively describing, analyzing, and making inferences about numerical data.
statistics: facts or data of a numerical kind, assembled, classified, and tabulated so as to present significant information about a given subject.
stereotype a belief about the personal attributes of a group of people. Stereotypes are sometimes overgeneralized, inaccurate, and resistant to new information.
Stereotype A fixed way of thinking about people that puts them into categories and doesn't allow for individual variation.
stereotype threat a disruptive concern, when facing a negative stereotype, that one will be evaluated based on a negative stereotype. Unlike self-fulfilling prophecies that hammer one's reputation into one's self-concept, stereotype threat situations have immediate effects.
Stereotype vulnerability A disturbing awareness among members of a negatively stereotyped group that anything one does, or anything about oneself that fits the stereotype, may confirm it as a self-characterization.
stereotypes Schemas by which people try to categorize complex groups. Group stereotypes are often negative, especially when applied to minority groups.
Stigma An attribute that serves to discredit a person in the eyes of others.
stillbirth: the birth of a dead fetus after 20 weeks.
stimulant An influence (typically, a drug) that has activating or excitatory effects on brain or bodily functions (e.g., amphetamines, Ritalin, cocaine).
stimulus Anything in the environment that the organism can detect and respond to.
stimulus generalization In classical conditioning, the tendency to respond to stimuli other than the original conditioned stimulus (CS). The greater the similarity between the CS and the new stimulus (CS+), the greater generalization will be. An analogous phenomenon in instrumental conditioning is a response to stimuli other than the original discriminative stimulus.
storage capacity The amount of information that can be retained in memory. See alsomagic number.
stranger: anxiety distress in the presence of unfamiliar people.
strategic retrieval A deliberate effort to recall information by supplying one’s own retrieval cues (e.g., "Let’s see, the last time I remember seeing my wallet was . . .").
Strategic self-presentation Conscious and deliberate efforts to shape other people's impressions in order to gain power, influence, sympathy or approval.
stratified sampling An experimental procedure in which each subgroup of the population is sampled in proportion to its size.
stress In psychopathology, the psychological or physical wear-and-tear that, together with a preexisting vulnerability, may lead to mental disorder. M ental or physical tension or strain.
stroboscopic movementSeeapparent movement.
Stroop effect A marked decrease in the speed of naming the colors in which various color names (such as green, red, etc.) are printed when the colors and the names are different. An important example of automatization.
structural principles (of language)Seeprescriptive rules.
structured personality test A personality test (e.g., the MMPI or CPI) that asks specific questions and requires specific answers.
subcortical structures Usually the forebrain structures, such as those comprising the limbic system and extrapyramidal motor system, that lie beneath the cortex.
subcortical: the lower areas of the brain, which are responsible for basic life functions.
Subculture A social group exhibiting a lifestyle sufficiently different to distinguish itself from others within the larger culture.
subjective contours Perceived contours that do not exist physically. We tend to complete figures that have gaps in them by perceiving a contour as continuing along its original path.
subjective values The outcomes an individual prefers; in Walter Mischel’s view, a determinant of behavior and an important individual difference.
subjects: members of a population who participate in a study.
Subliminal perception The processing of information which is below one's threshold of conscious awareness.
subroutines In a hierarchical organization, lower-level operations that function semiautonomously but are supervised by higher-level ones.
subtractive color mixture Color that results from the subtraction of one set of wavelengths from another set, commonly produced when mixing color pigments or superimposing two colored filters. See alsoadditive color mixture.
subtyping accommodating individuals who deviate from one's stereotype by splitting off a subgroup stereotype (such as "middle class Blacks" or "feminist women"). Subtyping protects stereotypes.
successive approximations The process of shaping a response by rewarding the steps toward the behavioral goal. See alsoshaping.
sudden infant death syndrome (SIDS): the sudden death of an apparently healthy infant, of unknown cause but believed to be related to some faulty mechanism in respiration control.
suicide: the act of killing oneself intentionally.
superego In Freud’s theory, reaction patterns that emerge from within the ego, represent the internalized rules of society, and come to control the ego by punishment with guilt. See alsoego, id.
superego: that part of the psyche that is critical of the self or ego and enforces moral standards: at an unconscious level it blocks unacceptable impulses of the id.
Superordinate goal A mutually shared goal that can be achieved only through intergroup cooperation. A shared goal that necessitates cooperative effort; a goal that overrides people's differences from one another.
Supplication Advertising one's weaknesses or one's dependence upon others in order to solicit help or sympathy.
surface structureSeephrase structure.
survey research: research that involves interviewing or administering questionnaires to large numbers of people.
syllogism A logic problem containing two premises and a conclusion that may or may not follow from them.
Symbolic interaction theory A contemporary sociological theory, inspired by Mead's insights and based on the premise that the self and social reality emerge due to the meaningful communication among people.
symbolic representation A type of mental representation that does not correspond to the physical characteristics of that which it represents. Thus, the word mouse does not resemble the small rodent it represents. Symbols Arbitrary signs of objects that stand in the place of those objects.
symmetrical distribution A distribution of numerical data in which deviations in either direction from the mean are equally frequent.
sympathetic nervous system The division of the autonomic nervous system that mobilizes the body’s energies for physical activity (e.g., increasing heart rate, sweating, and respiration). Its action is typically antagonistic to that of the parasympathetic nervous system.
symptoms In psychopathology, what the patient reports about his physical or mental condition (e.g., nervousness, hearing voices). See alsosigns, syndrome.
synapse The juncture of two neurons, consisting of the presynaptic and postsynaptic membranes, and — in nonelectrical synapses — the synaptic gap between them.
synaptic reuptakeSeereuptake.
synaptic vesiclesSeevesicles.
syndrome A pattern of signs and symptoms that tend to co-occur.
syntax The system by which words are arranged into meaningful phrases and sentences.
systematic desensitization A behavior therapy that tries to remove anxiety connected to various stimuli by gradually counterconditioning to them a response incompatible with fear, usually muscular relaxation. The stimuli are usually evoked as mental images according to an anxiety hierarchy, whereby relaxation is conditioned to the less frightening stimuli before the more frightening ones.
tacit knowledge Practical "how to" knowledge that is unwittingly accumulated from everyday experience.
tape-recorder theory of memory The erroneous view that the brain contains an indelible record of everything one experiences.
taste buds The receptor organs for taste, located atop the tongue.
TautologySomething that is true by virtue of its logical form alone.
taxonomy A classification system.
technical eclecticism In the practice of psychotherapy, the use of whatever techniques work best for particular persons and problems. This approach contrasts with views that therapy should proceed accord-ing to a consistent therapeutic orientation (e.g., psychodynamic, behavioral, etc.).
telegraphic speech: speech of 1 to 2-year-olds in which two or more meaningful words are put together to form brief sentences.
temperament In modern usage, a characteristic level of reactivity and energy, often thought to be constitutional.
temporal contiguity Co-occurrence of stimuli. A condition Pavlov thought would be favorable for forming associations; actually forward pairing is most favorable. See alsobackward pairing, forward pairing, simultaneous pairing.
temporal lobe The lobe of the cortex lying below the temples in each cerebral hemisphere, which includes the primary auditory projection area, Wernicke’s area, and subcortically, the amygdala and hippocampus.
temporal summation The process whereby a stimulus that is below threshold will elicit a reflex if the stimulus occurs repeatedly.
teratogen: an agent, as a chemical, disease, and so on, that causes malformation of a fetus.
territory A term used by ethologists to describe a region a particular animal stakes out as its own. The territory holder is usually a male, but in some species the territory is held by a mating pair or by a group.
test profile A graphical indication of an individual’s performance on several components of a test. This is often useful for guidance or clinical evaluation because it indicates that person’s pattern of abilities or traits.
testosterone The principal male sex hormone in mammals. See alsoandrogen.
test-retest method A way of ascertaining the reliability of a test. It involves administering the same test to the same group of subjects after a certain time lag and assessing the correlation of scores. See alsoreliability coefficient.
tetrahydrocannabinol (THC): the hallucinatory chemical that is the principal and most active ingredient in marijuana.
texture elements Surface variations that indicate the texture of an object (e.g., pebbles on a trail or blades of grass on a lawn) and whose spacing can be used to judge an object’s size or one’s distance from the object.
texture gradient A distance cue based on changes in surface texture that depend on how far away the observer is.
thalamus A part of the lower portion of the forebrain that serves as a major relay and integration center for sensory information.
thanatologists: those who examine all aspects of death, including biological, psychological, and social issues.
thanatology: the study of death, especially of the medical, psychological, and social problems associated with dying.
That's-not-all strategy A two-step compliance technique in which the influencer makes a large request, then immediately offers a discount or bonus before the initial request is refused.
Thematic Apperception Test (TAT) A projective technique in which persons are shown a set of pictures and asked to make up a story about each one.
theory an integrated set of principles that explain and predict observed events. An organized system of ideas that seeks to explain why two or more events are related.
theory of mind A set of interrelated concepts used to try to make sense of our own mental processes and those of others, including the variability of beliefs and desires. An awareness and understanding of others' states of mind and accompanying actions.
Theory of planned behavior The theory that people's conscious decisions to engage in specific actions are determined by their attitudes toward the behavior in question, the relevant subjective norms, and their perceived behavioral control.
Theory of psychological reactance The theory that people believe they possess specific behavioral freedoms, and that they will react against and resent attempts to limit this sense of freedom.
theory: an integrated set of statements that explain various phenomena.
therapeutic alliance In psychotherapy, the structuring of the patient-therapist relationship such that the patient considers the therapist a sympathetic ally when confronting problems.
Therapy: the practice of giving systematic attention to another`s process with the intention of facilitating (literally `making easier`) the other`s personal growth or self-discovery.
thermoreceptors Specialized neurons that respond to the temperature of bodily fluids circulating throughout the brain.
thermoregulation The process by which organisms maintain a constant body temperature. For ectotherms, it is matter of external behavior such as seeking sun or shade, while for endotherms it also involves numerous internal adjustments such as sweating.
third-variable problem The major obstacle to discerning causation from correlation, because two variables may be correlated only because of the operation of a third variable. For example, sales of ice cream are correlated with rates of violent crime, but only because both increase during hot weather and decrease during cold weather.
threat displays In animals, dramatic patterns of behavior (e.g., movements, calls, coloration changes) that indicate the intent to fight if challenged further. Threat displays often allow animals to circumvent actual combat, which is far more costly.
Threat-to-self-esteem model A theory stating that if receiving help contains negative self-messages, recipients are likely to feel threatened and respond negatively.
threshold The value a stimulus must reach to produce a response.
tip-of-the-tongue phenomenon The condition in which one re-mains on the verge of retrieving a word or name but continues to be unsuccessful.
toddlerhood: ages 1 to 2.
token economy An arrangement for operant behavior modification, usually in institutional settings. Certain responses (e.g., cleaning one’s room, talking to others) are reinforced with tokens that can be exchanged for desirable items.
toleranceSeeopponent-process theory of motivation.
top-down processes Processes in form recognition that begin with larger units and then proceed to smaller units (e.g., from phrases to words to letters). This contrasts with bottom-up processes, which start with smaller component parts and gradually build up to the larger units (e.g., from letters to words to phrases). One demonstration of top-down processing is provided by context effects in which knowledge or expectations affect what one sees.
trace consolidation hypothesis The hypothesis that newly acquired memory traces undergo a gradual change that makes them more and more resistant to any disturbance.
Trait A relatively stable way in which individuals differ from one another, a distinguishing quality or characteristic, as of personality
trait theory The view that differences in personality are best characterized in terms of underlying, possibly innate, attributes (traits) that predispose one toward patterns of thinking and behavior that are essentially consistent over time and across situations. See alsobehavioral-cognitive approach, humanistic approach, psychodynamic approach, situationism, sociocultural approach.
Transactive memory A collectively shared memory system for encoding, storing, and retrieving information that is greater than any individual memories.
transduction The process by which a receptor reacts to some physical stimulus (e.g., light or pressure) and creates action potentials in another neuron.
transection Surgical cutting of a nerve tract or brain region, performed to isolate functionally the regions on either side.
transfer of training tests Procedures used to ascertain whether skills learned in one setting generalize to other settings.
transference In psychoanalysis, the patient’s tendency to react toward her analyst as she did originally toward her own parents (or other people central in her early life). The patient comes to respond to the therapist as if the analyst were some significant person from the patients past, usually the father or mother. Then needs and the wishes from the patient's past are then reactivated "in the transference" and they are relived in relation to the analyst. In classical analysis the patient forms a libidinal attachment to the analyst. This revivification of old longings and conflicts provides an arena in the present where earlier problems can be brought to awareness and resolved. From a classical point of view the transference tends to be positive (loving), negative (hateful or aggressive), , or ambivalent(both loving and hating). From a self psychological point of view the there are two major kinds of reactivation which are seen in the transference, (1) the hope of finding a good selfobject who will provide longed for previously missing self object functions (mirroring, idealization, twinship, and alter ego), and (2) the dread that the hurtful frustrating experiences from the past will be repeated.
Transformational leader A leader who changes (transforms) the outlook and behavior of followers (also referred to as a charismatic leader).
Transpersonal: literally - that which is beyond the purely personal - i.e. that which connects, unites and transcends us but which is experienced and given meaning individually.
transposition The phenomenon whereby visual and auditory patterns (i.e., figures and melodies) remain essentially the same even though the parts of which they are composed change.
Treatment group Experimental participants who are exposed to nonzero levels of the independent variable.
tree diagram A branched diagram depicting a hierarchical structure.
trephining Drilling or cutting holes in the skull. Purportedly once done by demonologically oriented practitioners to allow the escape of evil spirits that were believed to be causing mental disorders.
triarchic theory of intelligence: a theory stating that intelligence consists of three factors: information-processing skills, context, and experience.
trichromatic color vision The principle underlying color vision. Color vision occurs through the operation of three sets of cones, each maximally sensitive to a different wavelength of light.
tricyclic antidepressants (tricyclics) An early class of antidepressant medications that includes Tofranil and Pamelor. Because of unfavorable side effects, they have been largely supplanted by selective serotonin reuptake inhibitors (SSRIs).
trimester: a period or term of three calendar months (13 weeks).
trophoblast: a layer of nutritive ectoderm outside the blastoderm, by which the fertilized ovum is attached to the uterine wall and the developing embryo receives its nourishment.
true hermaphroditism Rare type of intersexuality in which an individual possesses reproductive tissue of both sexes (e.g., testes and ovaries).
two-factor theory of emotion arousal 3 label 5 emotion.
Two-factor theory of emotions A theory that emotional experience is based on two factors: physiological arousal and cognitive labeling of the cause of that arousal.
two-step flow of communication the process by which media influence often occurs through opinion leaders, who in turn influence others.
two-syndrome hypothesis of schizophrenia The hypothesis that there may actually be two supercategories of schizophrenia, Type I and Type II. According to the hypothesis, Type I is produced by a malfunction of transmitters, especially dopamine, and produces primarily positive symptoms, while Type II is accompanied by reduced frontal lobe activity and sometimes cerebral atrophy, which lead to negative symptoms.
Type A behavior pattern A constellation of behavior characterized by impatience, competitiveness, and aggressiveness when thwarted. It was believed to be associated with greater incidence of coronary heart disease. See alsoType B personality.
Type B behavior pattern In contrast to the Type A pattern, Type B’s are easygoing, less hurried, less competitive, and friendlier; they are less predisposed to coronary heart disease. See alsoType A personality.