Click on a letter to find a definition.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

A

Abnormal behaviour: Behaviour that is personally distressful, personally dysfunctional, and/or culturally deviant in ways that other people judge as inappropriate or maladaptive.

Absolute refractory period: The brief time interval following an action potential when a neuron is incapable of being stimulated to fire another impulse.

Absolute threshold: The lowest intensity at which a stimulus can be detected 50 percent of the time.

Abstinence violation effect: A response to lapse in which a person blames them self and concludes that they are incapable of resisting high-risk situations.

Accommodation: In cognitive development, the process by which new experiences cause existing schemas to change.

Acetylcholine (ACh): An excitatory neurotransmitter that operates at synapses with muscles and is also the transmitter in some neural networks involved in memory.

Achievement goal theory: A theory of achievement motivation that stresses the goals (ego versus mastery) and motivational climates that influence achievement strivings.

Achievement test: A measure of an individual's degree of accomplishment in a particular subject or task based on a relatively standardized set of experiences.

Action potential: A nerve impulse resulting from the depolarization of an axon's cell membrane.

Activation-synthesis theory: A theory suggesting that dreams represent the brain's attempt to interpret random patterns of neural activation triggered by the brain stem during sleep.

Adaptations: Biological and behavioural changes that allow organisms to meet recurring environmental challenges to their survival, thereby increasing their reproductive ability.

Adaptive significance: The manner in which a particular behaviour enhances an organism's chances of survival and reproduction in its natural environment.

Adolescence: The period of development that involves a gradual transition between childhood and adulthood.

Adolescent egocentrism: Highly self-focused thinking, particularly in the early teenage years.

Adoption study: A research method in behavioural genetics in which adopted people are compared on some characteristic with both their biological and adoptive parents in an attempt to determine the strength of the characteristic's genetic component.

Adrenal glands: Endocrine glands that release stresshormones, including, catecholamines and corticosteroids.

Aerobic exercise: Sustained activity that elevates the heart rate and increases the body's need for oxygen.

Agonist: A drug that increases or mimics the activity of a neurotransmitter.

Agoraphobia: A cluster of phobias (irrational fears) related to being in places or situations from which escape might be difficult in the event of sudden incapacitation(e.g., on a bridge or a bus, in crowds or wide open spaces).

Alcohol myopia: An inability to pay attention to as much information as when sober leading to unstable perceptions and reactions which in turn increase the risk of misunderstandings, misinterpretations and poor judgement as to the consequences of actions.

Algorithms: Organized methods for solving a problem (and producing a result) which are expressed as a finite sequence of clearly defined steps to accomplish this (for example, a mathematical formula).

All-or-none law: States that an action potential is not proportional to the intensity of stimulation; a neuron either fires with maximum intensity or it does not fire (compare with graded potential).

Alpha waves: A brain-wave pattern of 8 to 12 cycles per second that is characteristic of humans in a relaxed, drowsy state.

Alzheimer's disease (AD): A brain disorder, typically but not always occurring in old age, whose prominent features are memory loss and confused thinking.

Amplitude: The vertical size of the sound wave, which gives rise to the perception of loudness and is measured in terms of decibels.

Amygdala: A structure in the limbic system that helps organize emotional response patterns.

Anorexia nervosa: An eating disorder involving a severe and sometimes fatal restriction of food intake.

Antagonist: A drug that inhibits or decreases the action of a neurotransmitter.

Anterograde amnesia:Memory loss for events that occur after the initial onset of amnesia.

Anticipatory nausea and vomiting (ANV): Classically conditioned nausea and vomiting that occur when cancer patients are exposed to stimuli associated with their treatment.

Antigens: Literally, antibody generators, or foreign substances that activate the cells of the immune system.

Antisocial personality disorder: A long-term stable disorder characterized by a lack of conscience, defects in empathy and a tendency to act out in an impulsive manner that disregards future consequences.

Anxiety: An unpleasant emotional state characterised by apprehension accompanied by physiological arousal and fearful behaviour.

Anxiety disorders: A group of behaviour disorders in which anxiety and associated maladaptive behaviours are the core of the disturbance.

Aphasia: The partial or total loss of ability to understand speech (receptive aphasia) or to produce it (productive aphasia).

Applied behaviour analysis: A process in which operant conditioning is combined with scientific data collection to solve individual and societal problems.

Applied research: Research that is designed to solve or examine specific, practical or 'real world' problems.

Approach-approach conflict: A conflict creating indecision and vacillation in an individual because they are simultaneously confronted with two equally attractive but incompatible alternatives.

Approach-avoidance conflict: A conflict creating indecision and vacillation in an individual because they are simultaneously attracted to and repelled by the same goal.

Aptitude test: A measure of a person's ability to profit from further training or experience in an occupation or skill; usually based on a measure of skills gained over a person's lifetime rather than during a specific course of study.

Archetypes: In Jung's theory, innate concepts and memories (e.g., God, the hero, the good mother); that reside in the collective unconscious.

Archival measures: The usage of records or past documents that contain information about some type of behaviour.

Assimilation: In cognitive development, the process by which new experiences are incorporated into existing schemas.

Association cortex: The areas of the cerebral cortex that do not have sensory or motor functions but are involved in the integration of neural activity that underlies perception, language, and other higher-order mental processes.

Associative network: The view that long-term memory is organized as a massive network of associated ideas and concepts.

Attachment: The strong emotional bond that develops between two people; developmentally, the bond between children and their primary caregivers.

Attention deficit/hyperactivity disorder (ADHD): A disorder, usually originating in childhood, that may take the form of attentional difficulties, hyperactivity/impulsivity, or a combination of the two that results in impaired functioning.

Attitude: A positive or negative evaluative reaction toward a stimulus (e.g., toward a person, action, object, or concept).

Attribution: A judgment about the causes of our own and other people's behaviour.

Authoritarian parents: Caregivers who exert control over their children within a cold, unresponsive, or rejecting relationship.

Authoritative parents: Caregivers who are controlling but warm; they establish and enforce clear rules within a caring, supportive atmosphere.

Autistic disorder: A severe developmental disorder characterized by extreme impairments relating to social interaction and communication, accompanied by highly repetitive and rigid patterns of behaviour.

Autobiographical memories: Recollections of personally experienced events that make up the "story of our life".

Automatic (unconscious) processing: Mental activities that occur with minimal or no conscious control or awareness.

Autonomic nervous system (ANS): The branch of the peripheral nervous system that activates the body's involuntary muscles (e.g., heart) and internal organs.The ANS is divided into the sympathetic nervous system and the parasympathetic nervous system.

Availability heuristic: A rule of thumb used to make likelihood judgments based on how easily examples of that category of events come to mind or are "available" in memory.

Aversion therapy: A form of therapy in which a conditioned stimulus that currently evokes a positive but maladaptive response is paired with a noxious and unpleasant unconditioned stimulus, in an attempt to condition a repulsion toward the conditioned stimulus.

Aversive punishment (positive punishment, punishment by application): A type of punishment in which an operant response is weakened by the subsequent presentation of a noxious and unpleasant stimulus.

Avoidance-avoidance conflict: A conflict creating indecision and vacillation in an individual because they are confronted with a choice between two equally undesirable alternatives.

Avoidance conditioning: A form of learning in which an organism learns a response in order to avoid an undesirable consequence.

Axon: An extension from one side of the neuron cell body that conducts nerve impulses to other neurons, muscles, or glands.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

B

Basic research: Research designed to obtain knowledge for its own sake.

Basilar membrane: A membrane that runs the length of the cochlea and contains the organ of Corti and its sound receptor hair; when stimulated these hair cells produce the neural effects of auditory stimulation.

Behavioural activation system (BAS): A neural system that is activated by cues indicating potential reward and positive need gratification. Activity in this neural system causes the person to begin or to increase movement toward positive goals in anticipation of pleasure.

Behavioural activation treatment: A treatment for depression that engages clients in life activities designed to increase positive reinforcement in their lives.

Behavioural assessment: The measurement of behaviour through direct observation and application of a coding system.

Behavioural inhibition system (BIS): A neural system that is activated by cues indicating potential pain, non-reinforcement, and punishment. Activity in this neural system produces fear, inhibition of behaviour, as well as escape and avoidance behaviours.

Behavioural neuroscience: A subfield of psychology that examines brain processes and other physiological functions that underlie our behaviour, sensory experiences, emotions, and thoughts.

Behavioural perspective: A view that emphasizes how the environment and learning experiences shape and control behaviour.

Behavioural signatures: Individually consistent ways of responding in particular classes of situations.

Behavioural genetics: The scientific study of the role of genetic inheritance in behaviour.

Behaviourism: A school of psychology that emphasizes the effects of learning and environmental control on behaviour and maintains that the proper subject matter of psychology is observable behaviour.

Behaviour modification: Therapeutic procedures based on operant conditioning principles, such as positive reinforcement, operant extinction, and punishment, in order to increase the frequency of desired behaviours and/or decrease the frequency of problem behaviours.

Behaviour-outcome expectancy: The subjective likelihood that a particular consequence will follow a particular behaviour in a given situation.

Belief bias: The tendency to abandon logical rules and to form a conclusion based on one's existing beliefs.

Beta waves: A brain-wave pattern of 15 to 30 cycles per second that is characteristic of humans who are in an alert waking state.

Bilingualism: The use of two languages in daily life.

Binocular depth cues: Depth cues that require the use of both eyes.

Binocular disparity: The binocular depth cue produced by the projection of slightly different images of an object on the retinas of the two eyes.

Biologically based mechanisms: Evolved biological structures that receive input from the environment, process the information, and respond to it.

Biological perspective: A view that focuses on the role of biological factors in behaviour, including biochemical and brain processes, as well as genetic and evolutionary factors.

Bipolar disorder: A mood disorder in which intermittent mania appears against a background of depression.

Blindsight: A disorder in which people are blind in part of their visual field yet, in special tests, respond to stimuli in that field despite reporting that they cannot see those stimuli.

Blood-brain barrier: A specialized lining of cells in the brain's blood vessels that screens out foreign substances while letting nutrients pass through to neurons.

Bottom-up processing: Perceptual processes that begin with the analysis of individual elements of the stimulus and work up to the brain's integration of them into a unified perception.

Borderline personality disorder (BPD): A serious personality disorder characterized by severe instability in behaviour, emotion, identity, and interpersonal relationships.

Brain stem: The portion of the brain formed by the swelling of the spinal cord as it enters the skull; its structures regulate basic survival functions of the body, such as heart rate and respiration.

British empiricism: A 17th-century school of philosophy championed by Locke, according to which all the contents of the mind are gained experientially through the senses.

Broca's area: A region of the left frontal lobe involved in speech production.

Bulimia nervosa: An eating disorder that involves a repeated cycle of binge eating followed by purging of the food.

Bystander effect: The principle that the presence of multiple bystanders inhibits each person's tendency to help, largely due to social comparison or diffusion of responsibility.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

C

Cannon-Bard theory: A theory of emotion that proposed that the thalamus sends simultaneous messages to the cortex (producing our experience of emotion) and to the viscera and skeletal muscles, producing co-occurring actions and physiological responses.

Case study: An in-depth analysis of an individual, group, or event.

Catatonic schizophrenia: A schizophrenic reaction characterized by alternating stuporous states and agitated excitement.

Catharsis: The process of expressing strongly felt but usually repressed emotions.

Central nervous system: The portion of the nervous system that includes the brain and the spinal cord.

Central route to persuasion: Occurs when people think carefully about a message and are influenced because they find the arguments compelling.

Cephalocaudal principle: The tendency for physical development to proceed in a head-to-foot direction.

Cerebellum: A convoluted hindbrain structure involved in motor coordination and some aspects of learning and memory.

Cerebral cortex: The grey, convoluted outer covering of the brain that is the seat of higher-order sensory, motor, perceptual, and mental processes.

Cerebrum: The most advanced portion of the brain, containing the cerebral cortex and underlying structures.

Chaining: An operant conditioning procedure used to develop a sequence (chain) of responses by reinforcing each response with the opportunity to perform the next response.

Cholecystokinin (CCK): A peptide (hormone) that helps produce satiety and cessation of eating.

Chromosomes: Tightly coiled strands of deoxyribonucleic acid (DNA) and protein that contain the genes.

Chunking: Combining individual items into larger units of meaning.

Circadian rhythms: Biological cycles within the body that occur on an approximately 24-hour cycle.

Classical conditioning: A procedure in which a formerly neutral stimulus (the conditioned stimulus) comes to elicit a conditioned response by virtue of being paired with an unconditioned stimulus that naturally elicits a similar response (the unconditioned response).

Cochlea: A small fluid filled coil-shaped structure of the inner ear that contains the receptors for sound.

Cognitive-affective personality system (CAPS): A model that organizes five "person variables" that account for how a person might respond to a particular situation; the dynamic interplay among these five factors, together with the characteristics of the situation, accounts for individual differences between people, as well as differences in people's behaviour across different situations.

Cognitive appraisal: The process of making judgments about situations, personal capabilities, likely consequences, and personal meaning of consequences.

Cognitive behaviourism: A behavioural approach that incorporates cognitive concepts, suggesting that the environment influences our behaviour by affecting our thoughts and giving us information.

Cognitive map: A mental representation of the spatial layout of an area.

Cognitive neuroscience: An area of psychology that intersects the subfields of cognitive psychology and physiological psychology and examines brain processes that underlie mental activity.

Cognitive perspective: A view that emphasizes humans as rational information processors and problem solvers, and that focuses on the mental processes that influence behaviour.

Cognitive-process dream theories: Approaches that focus on how (rather than why) we dream, and propose that dreaming and waking thought are produced by the same mental systems in the brain.

Cognitive process theories: Approaches to intelligence that analyze the mental processes that underlie intelligent thinking.

Cognitive psychology: An area of psychology that specializes in studying mental processes such as thinking, memory, planning, reasoning, attention, and perception.

Cognitive relaxation: A state of mental quiescence produced by meditation and other methods.

Cognitive restructuring: A cognitive stress-reduction approach that involves attempts to detect, dispute, and change maladaptive or irrational ideas that trigger negative emotions.

Collective unconscious: Jung's notion of an unconscious that consists of innate ancestral memories.

Collectivism: A cultural orientation that emphasizes the achievement of group rather than individual goals and in which personal identity is largely defined by ties to the larger social group (compare with individualism).

Common factors: Therapeutic elements that are possessed by virtually any type of therapy and that may contribute to the similar positive effects shown by many different treatment approaches.

Communicator credibility: The degree to which an audience views a communicator as believable, largely based on the communicator's expertise and trustworthiness.

Companionate love: An affectionate relationship characterized by commitment and caring about the partner's wellbeing; sometimes contrasted with passionate love, which is more intensely emotional.

Compensatory response: A bodily response that opposes a drug's effects and occurs in an attempt to restore homeostasis.

Competency: The legal fitness of a defendant to stand trial based on their mental capability of understanding the nature of the charges against them, participate meaningfully in the trial, and consulting with their lawyer.

Competency-focused intervention: Prevention programs that are designed to enhance personal resources needed to cope with situations that might otherwise cause psychological disorders.

Compulsion: A repetitive act that the person feels compelled to carry out, often in response to an obsessive thought or image.

Computerized axial tomography (CT, or CAT) scan: A method of scanning the brain with narrow beams of X rays that are then analyzed and combined by a computer to provide pictures of brain structures from many different angles.

Concept: A mental category containing similar objects, people, and events.

Concordance: The likelihood that two people share a particular characteristic.

Concrete operational stage: In Piaget's theory, the stage of cognitive development during which children can perform basic mental operations concerning problems that involve tangible (i.e.,"concrete") objects and situations.

Conditioned response (CR):In classical conditioning, a response to a conditioned stimulus; the conditioned response is established by pairing a conditioned stimulus with an unconditioned stimulus that evokes a similar response.

Conditioned stimulus (CS): A stimulus that comes to evoke a conditioned response after being paired with an unconditioned stimulus.

Conditioned taste aversion: A learned repulsion to a food that formerly was neutral or desired, by virtue of pairing the food with an aversive unconditioned stimulus.

Conditions of worth: Internalized standards for self-worth fostered by conditional positive regard from others.

Conduct disorder: A pattern of abnormal behaviour in which children violate important social norms and show disregard for the rights of others.

Conduction deafness: Hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea.

Cones: Photoreceptors in the retina that function best in bright light and are differentially sensitive to red, green, or blue wavelengths.

Confirmation bias: The tendency to seek and favour information that reinforces our beliefs rather than to be open to disconfirming information.

Confounding of variables: In experiments, a situation in which the independent variable is intertwined or mixed up with another, uncontrolled variable; thus we cannot tell which variable is responsible for changes in the behaviour of interest (i.e., in the dependent variable).

Congruence: Consistency between self- perception and experience

Consciousness: Our moment-to-moment awareness of ourselves and our environment; consciousness involves selective attention to ongoing thoughts, perceptions, and feelings.

Conservation: The principle that basic properties of objects, such as their mass or quantity, stay the same (are "conserved") even though their outward appearance may change.

Construct validity: The extent to which a test measures the psychological construct (e.g., intelligence, anxiety) that it is purported to measure.

Content validity: The extent to which test items adequately sample the domain that the test is supposed to measure (e.g., intelligence, mathematical reasoning).

Context-dependent memory: The phenomenon that it is typically easier to remember something in the same environment in which it was originally learned or experienced.

Continuous reinforcement: A reinforcement schedule in which each response of a particular type is followed by reinforcement.

Control group: In an experiment, the group that either is not exposed to the treatment or receives a zero level of the independent variable.

Controlled (conscious) processing: Mental processing that requires volitional control and attentiveness.

Conventional moral reasoning: According to Kohlberg, the stage at which moral judgments are based on conformity to social expectations, laws, and duties.

Convergence: A binocular depth cue produced by the muscles that rotate the eyes as they focus on nearby objects.

Conversion disorder: A disorder in which serious neurological symptoms, such as paralysis, loss of sensation, or blindness suddenly occur without physical cause.

Coping self-efficacy: Beliefs relating to our ability to deal effectively with a stressful stimulus or situation, including pain.

Corpus callosum: A broad band of white, myelinated fibres that connects the left and right cerebral hemispheres and allows the two hemispheres to communicate with one another.

Correlational research: Research that measures two or more naturally occurring variables and examines whether they are statistically related.

Correlation coefficient: A statistic that indicates the direction and strength of a relation between two variables; values can range from +1.00 to -1.00.

Counterbalancing: In experiments, a procedure used in designs where when each participant engages in all of the conditions. The order of the conditions is altered for different participants so that, overall, no condition has an order advantage relative to the other conditions.

Counter-conditioning: The process of conditioning an incompatible response to a particular stimulus to eliminate a maladaptive response (e.g., anxiety), as occurs in systematic desensitization.

Creativity: The ability to produce something that is both new and valuable.

Criterion-related validity: The ability of psychological test scores to correlate with some present or future behaviour assumed to be influenced by the construct measured by the test.

Critical periods: Limited time periods during which plasticity can occur as a result of experience or in response to injury; in development, a time period in which exposure to particular kinds of stimulation is required for normal growth to occur.

Cross-sectional design: A research design that simultaneously compares people of different ages at a particular point in time.

Crystallized intelligence (gc): Intellectual abilities that depend on a store of information and the acquisition of particular skills (compare with fluid intelligence).

Cultural display rules: Cultural norms that regulate when and how emotions are expressed.

Culturally competent therapists: Practitioners who have a set of therapeutic skills, including scientific mindedness, the ability to consider both cultural and individual factors, and the capacity to introduce culture-specific elements into therapy with people from minority cultures.

Cultural psychology: An area of psychology, sometimes called cross-cultural psychology, that explores how culture is transmitted to its members and examines psychological similarities and differences that occur between people from diverse cultures.

Culture: The enduring values, beliefs, behaviours, and traditions that are shared by a large group of people and passed from one generation to the next.

Culture-bound disorders: Behaviour disorders whose specific forms are restricted to one particular cultural context.

Cytokines: Chemical molecules released by immune cells that produce fever and inflammation, promote the healing of injured tissue, and activate and direct other immune cells.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W| X | Y | Z

D

Dark adaptation: The progressive increase in brightness sensitivity that occurs over time as photopigments regenerate themselves during exposure to low levels of illumination.

Decay theory: Maintains that with time and disuse, the physical memory trace in the nervous system fades away.

Decibel: A logarithmic measure of sound intensity.

Decision criterion: In signal detection theory, the potentially changing standard of how certain a person must be that a stimulus is present in order to report its presence.

Declarative memory: Our memory for factual knowledge, which comprises two subcategories: knowledge pertaining to personal experiences (episodic memory) and knowledge of general facts and language (semantic memory).

Deductive reasoning: Reasoning from a general principle to a specific case.

Deep structure: A linguistic term that refers to the underlying meaning of a spoken or written sentence; the meanings that make up deep structure are stored as concepts and rules in long-term memory.

Defence mechanisms: Unconscious processes that help us cope with anxiety and the pain of traumatic experiences. Defence mechanisms prevent the expression of anxiety-arousing impulses or allow them to appear in disguised forms.

Deindividuation: A state of increased anonymity in which a person, often as part of a group or crowd, engages in disinhibited behaviour.

Deinstitutionalization movement: The attempt to move the primary locus of treatment from mental hospitals to the community.

Delta waves: Low-frequency, high-amplitude brain waves that occur in stage 3 sleep and predominate in stage 4 sleep.

Delusions: False beliefs, for example persecution or grandeur, that are sustained in the face of evidence that normally would be sufficient to destroy them.

Demand characteristics: Cues in an experimental setting that influence the participants' perception of what is expected of them and that systematically influence their behaviour within that setting

Dementia: The gradual loss of cognitive abilities that accompanies brain deterioration and interferes with normal functioning.

Dendrites: Small branching fibers that extend from the soma of a neuron and receive messages from adjacent neurons.

Dependent variable: In an experiment, the factor measured by the researcher that presumably is influenced by the independent variable.

Depressants: Drugsthat reduce neural activity and can decrease feelings of tension and anxiety. These include alcohol, barbiturates, and tranquilizers.

Depressive attributional pattern: The tendency of depressed people to attribute negative outcomes to their own inadequacies and positive outcomes to factors outside of themselves.

Depressive cognitive triad: A pattern of negative evaluations of the self, the world, and the future often found in depressed people.

Descriptive research: Research in which the main goal is to carefully describe how organisms behave, particularly in natural settings.

Descriptive statistics: Statistics that summarize and describe the characteristics of a set of scores.

Diagnostic reliability: Refers to agreement among clinicians making diagnostic judgments.

Dialectical behaviour therapy (DBT): A recently developed cognitive-behavioural treatment for borderline personality disorder.

Difference threshold: The smallest physical difference between two stimuli that can still be recognized as a difference; operationally defined as the point at which the stimuli are recognized as different half of the time; also called the just noticeable difference

Discourse: The combining of sentences into larger language units, such as paragraphs, articles, novels, and so on.

Discrimination (classical conditioning): The occurrence of a conditioned response to one stimulus but not to another stimulus.

Discrimination (social behaviour): Treating people unfairly based on the group to which they belong.

Discriminative stimulus: An antecedent stimulus that signals the likelihood of certain consequences if a response is made.

Disorganized schizophrenia: A schizophrenic disorder marked by verbal incoherence, disordered thought processes, disorganized behaviour, and inappropriate emotional responses.

Displacement: The capacity of language to represent objects and conditions that are not physically present.

Dissociation theories(of hypnosis): Views that focus on hypnosis as an altered state involving a division ("dissociation") consciousness; one theory proposes that the hypnotized person simultaneously experiences two streams of consciousness that are cut off from one another.

Dissociative disorders: Disorders that involve a major dissociation of personal identity, memory or consciousness.

Dissociative identity disorder (DID): Dissociative disorder in which two or more separate identities or personalities coexist within an individual.

Divergent thinking: A creative form of thinking that involves generating novel ideas that diverge from the normal ways of thinking about something.

Divided attention: The ability to perform more than one activity at the same time.

Dodo bird verdict: The conclusion reached by some psychotherapy researchers that virtually all treatment approaches have similar success rates.

Door-in-the-face technique: A manipulation technique in which a persuader makes a large request, expecting you to reject it, and then presents a smaller request.

Dopamine hypothesis: States that the symptoms of schizophrenia are produced by overactivity of the dopamine system in areas of the brain that regulate emotional expression, motivated behaviour, and cognitive functioning.

Double-blind procedure: A procedure which both the participant and the experimenter are kept unaware of the research condition to which the participant has been assigned.

Downward comparison: Seeing oneself as better off than the standard for comparison.

Drive: A state of internal tension that motivates an organism to behave in ways that reduce this tension.

Dual coding theory: Maintains that if we encode information using both verbal and imagery codes, the chances improve that at least one of the two codes will be available later to support recall.

Dual-process theory: A modern theory of colour vision that combines the trichromatic and opponent-process theories. Light waves are coded by red-, blue-, and green-sensitive cones in the retina and by opponent processes thereafter in the visual system.

Dynamic testing: A procedure in which static (standardized testing) is followed up with an interaction in which the examiner gives the subject guided feedback on how to improve performance and observes how the subject utilizes the information.

Dysthymia: A depressive mood disorder of moderate intensity that occurs over long period of time but does not disrupt functioning as a major depression does.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W| X | Y | Z

E

Eclecticism: An approach to therapy that incorporates principles and procedures from multiple therapies to provide the most suitable treatment to a client.

Effect size: In meta-analysis, a measure of treatment effectiveness that indicates what percentage of treated clients improve more than the average untreated client.

Ego: An aspect of Freud’s tri-partheid personality theory; the "executive" of the personality that is partly conscious and that mediates between the impulses of the id, the prohibitions of the superego, and the dictates of reality.

Ego-approach goals: An achievement orientation that focuses on being judged successful as a result of outperforming others.

Ego-avoidance goals: An achievement orientation that focuses on avoiding negative judgments by self or others due to failing to outperform others.

Egocentrism: Difficulty in viewing the world from someone else's perspective.

Ego orientation: In achievement goal theory, an orientation that defines success in terms of performing at a higher level than others.

Elaborative rehearsal: Focusing on the meaning of information or relating it to other things we already know.

Electra complex: The female version of the Oedipus complex in which the female child experiences erotic feelings toward her father, desires to possess him sexually, and views her mother as a rival.

Electroencephalograph (EEG): A device used to record the simultaneous activity of many thousands of neurons through electrodes attached to the scalp.

Eliciting stimuli: Internal or external cues that evoke an emotional response.

Embryo: A scientific term for the prenatal organism during the 2nd week through the 8th week after conception.

Emotion: A pattern of cognitive, physiological, and behavioural responses to situations and events that have personal significance i.e. relevance to important goals or motives.

Emotional intelligence: The ability to respond adaptively in the emotional realm by reading and responding appropriately to others' emotions, to be aware of and have the ability to control one's own emotions.

Emotion-focused coping: Coping strategies directed at minimizing or reducing emotional responses to a stressor.

Emotion regulation: The processes by which we evaluate and modify our emotional reactions.

Empathy: The capacity for experiencing the same emotional response being exhibited by another person; in therapy, the ability of a therapist to view the world through the client's eyes and to understand the client's emotions.

Empathy-altruism hypothesis: The view that pure altruism does exist and that it is produced by the capacity to empathize with the person in need of aid.

Empirical approach: An approach to test construction in which items (regardless of their content) are chosen that differentiate between two groups that are known to differ on a particular personality variable.

Empirically supported therapies (ESTs): Psychotherapy and behaviour-change techniques that have been shown to be efficacious in controlled clinical trials; also referred to as evidence based therapies.

Encoding: Getting information into the memory system by translating it into a neural code that the brain processes and stores.

Encoding specificity principle: States that memory is enhanced when conditions present during retrieval match those that were present during encoding.

Endocrine system: The body's system of glands that secrete hormones into the bloodstream and thereby affect many bodily functions.

Endorphins: Natural opiate-like substances that are involved in pain reduction.

Entity theorist: An individual who believes that people's characteristics are fixed and relatively unchangeable.

Episodic memory: Our store of factual knowledge concerning personal experiences—when, where, and what happened in the episodes of our lives.

Equal status contact: The principle that prejudice between people is most likely to be reduced when they engage in sustained close contact, have equal status within the context of their interaction, work to achieve a common goal that requires cooperation, and are supported by broader social norms that encourage prejudice reduction.

Escape conditioning: A form of learning in which the organism learns to perform a behaviour in order to terminate an aversive stimulus.

Evolution: A change over time in the frequency with which particular genes, and the characteristics they produce, occur within an interbreeding population.

Evolutionary/circadian sleep models: The view that in the course of evolution, each species developed an adaptive circadian sleep-wake pattern that increased its chances of survival in relation to its environmental demands.

Evolutionary personality theory: A recently developed attempt to account for personality traits such as the Big Five in terms of the evolutionary history of the human species; these traits are thought to develop from processes of natural selection.

Evolutionary psychology: A field of study that focuses on the role of evolutionary processes (especially natural selection) in the development of adaptive psychological mechanisms and social behaviour in humans.

Expectancy- value theory: A cognitive theory stating that goal-directed behaviour is jointly influenced by (1) the person's expectancy that a particular behaviour will contribute to reaching <br> the goal and (2) how positively or negatively the person values the goal.

Experiment: A research method in which the researcher manipulates one or more independent variables under controlled conditions and measures the extent to which the manipulation produces changes in a dependent variable.

Experimental group: In an experiment, the group that receives a treatment or is exposed to an active level of the independent variable.

Experimenter expectancy effects (EEEs): Subtle and unintentional ways in which an experimenter influences participants to behave in a way that will confirm the experimenter's hypothesis.

Explicit memory: Conscious or intentional memory retrieval.

Explicit prejudice: Prejudice that is expressed publicly, as when talking with someone or responding to a questionnaire.

Exposure therapies: Therapeutic techniques designed to extinguish anxiety responses by exposing clients to anxiety arousing stimuli or situations while preventing escape or avoidance.

Expressed emotion: A family interaction pattern, involving criticism, hostility, and over involvement, that is associated with relapse in formerly hospitalized schizophrenic patients who return home.

Expressive behaviours: Observable behaviour that accompanies subjectively experienced emotions.

External validity: The degree to which the results of a study can be generalized to other people, settings, and conditions.

Extinction (classical conditioning): Occurs when a conditioned stimulus is presented without the unconditioned stimulus, causing the conditioned response to weaken and eventually stop occurring.

Extinction ( operant conditioning): See operant extinction.

Extrinsic motivation: Motivation to perform a behaviour to obtain external rewards and reinforces, such as money, status, attention, and praise.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

F

Facial feedback hypothesis: States that somatic feedback from facial muscles to the brain influences emotional experience.

Factor analysis: A statistical technique that permits a researcher to reduce a large number of measures to a small number of clusters or factors; it identifies the clusters of behaviour or test scores that are highly correlated with one another.

Fantasy-prone personality: The tendency of some people to spend much of their waking time living in a vivid, rich fantasy world that they control.

Feature detectors: Sensory neurons that respond to particular features of a stimulus, such as its shape, angle, or colour.

Feminist therapy: An orientation that focuses on women's issues and strives to help female clients achieve greater self-determination.

Foetal alcohol syndrome (FAS): A severe group of abnormalities that results from prenatal exposure to alcohol.

Foetus: A scientific term for the prenatal organism from the 9th week after conception until birth.

Figure-ground relations: Perceptual organization in which a focal stimulus is perceived as a figure against a background of other stimuli.

Fixation: A state of arrested development due to unresolved conflicts at a particular earlier psychosexual stage.

Fixed action pattern: An unlearned response that is automatically triggered by a simple (releaser) stimulus.

Fixed-interval (FI) schedule: A reinforcement schedule in which the first response of a particular type is reinforced after a constant time interval.

Fixed-ratio (FR) schedule: A reinforcement schedule in which reinforcement is given after a constant number of responses of a particular type.

Flashbulb memories: Recollections that seem so vivid and clear that we can picture them as if they were snapshots of moments in time.

Fluid intelligence (gf) : The ability to deal with novel problem-solving situations for which personal experience does not supply a solution (compare with crystallized intelligence).

Foot-in-the-door technique: A manipulation technique in which the persuader gets you to comply with a small request first and later presents a larger request.

Forebrain: Brain structures above the midbrain, including the thalamus, hypothalamus, limbic system, and the cerebral hemispheres; involved in higher-order sensory, motor, and cognitive functions.

Formal operational stage: In Piaget's theory, the period in which individuals are able to think logically and systematically about both concrete and abstract problems, form hypotheses, and test them a thoughtful way.

Fovea: A small area in the centre of the retina that contains only cones and where visual acuity is greatest.

Framing: The idea that the same information, problem, or choice options can be structured, presented, and thought about in different ways.

Free association: In psychoanalysis, the procedure of verbalizing all thoughts that enter consciousness without censorship.

Frequency: In audition, the number of cycles per second in a sound wave that responsible for the pitch of the sound; the measure of frequency is the hertz (Hz), which equals one cycle per second.

Frequency distribution: For a set of data, a table that shows how frequently each score value has occurred for a particular variable.

Frequency theory of pitch perception: Maintains that the number of nerve impulses sent to the brain by the hair cells the cochlea corresponds to the frequency of the sound wave; this theory is accurate at low frequencies.

Fully functioning persons: Rogers's term for self-actualized people who are free from unrealistic conditions of worth and who exhibit congruence, spontaneity, creativity, and a desire to develop still further.

Functional fixedness: A phenomenon often found in problem-solving tasks in which the customary use of an object interferes with its use in a novel situation.

Functionalism: An early school of American psychology that focused on the functions of consciousness and behaviour in helping organisms adapt to their environment and satisfy their needs.

Functional MRI (fMRI): A brain scanning procedure that produces pictures of blood flow in the brain taken less than a second apart.

Fundamental attribution error: The tendency to underestimate the impact of the situation and overestimate the role of personal factors when explaining other people's behaviour.

Fundamental emotional patterns:Emotional response patterns that are believed to be innate.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

G

Gate control theory: A theory of pain that postulates the existence of gating mechanisms in the spinal cord and brain that can increase or decrease the experience of pain by regulating the flow of pain impulses to the brain.

Gender constancy: Understanding that being male or female is a permanent part of a person.

Gender identity: The sense of "femaleness" or "maleness" that is an integral part of our identity.

Gender: Organized mental structures that contain our understanding of the attributes and behaviours that are appropriate and expected for males and females.

General adaptation syndrome (GAS): Selye's description of the body's responses to a stressor, which includes successive phases of alarm, resistance, and exhaustion.

Generalized anxiety disorder: A chronic state of diffuse, or "free-floating," anxiety that is not attached to specific situations or objects.

Generativity: The principle that, in any given language, symbols can be combined to generate an infinite number of messages that have novel meaning.

Genes: The biological units of heredity, located on the chromosomes.

Genotype: The specific genetic makeup of the individual, which may or may not be expressed in the observable phenotype.

Genuineness: The ability of a therapist to honestly express her or his feelings to a client.

Gestalt laws of perceptual organization: The notion that people group and interpret stimuli in accordance with similarity, proximity, closure, and continuity.

Gestalt psychology: German school of psychology that emphasized the natural organization of perceptual elements into wholes, or patterns, as well as the role of insight in problem solving.

g factor: A general intellectual capacity that underlies more specific intellectual abilities.

Glucose: A simple sugar that is the body's (and especially the brain's) major source of immediately usable fuel.

Graded potential: A change in the electrical potential of a neuron that is proportional to the intensity of the incoming stimulation but not sufficient to produce an action potential.

Grammar: In any given language, the set of rules that dictates how symbols can be combined to create meaningful units of communication.

Group polarization: When a group of like-minded people discusses an issue, the "average" opinion of group members tends to become more extreme.

Groupthink: The tendency of group members to suspend critical thinking because they are motivated to seek agreement.

Gustation: The sense of taste.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

H

Habituation: A decrease in the strength of a response to a repeated stimulus.

Hallucinations: False sensory perceptions that have a compelling sense of reality.

Hallucinogens: Drugs, such as LSD and PCP, that distort or intensify sensory experiences and evoke hallucinations and disordered thought processes.

Harm reduction: A prevention strategy that is designed not to eliminate a problem behaviour but to reduce its harmful consequences.

Health psychology: The study of psychological and behavioural factors in the prevention and treatment of illness and in the enhancement of health.

Hering's opponent-process theory: The colour vision theory stating that the retina contains three sets of colour receptors that respond differentially to red-green, blue-yellow, and black-white; the <br> opponent processes that result can produce a perception of any hue.

Heritability coefficient: A numerical estimate of the percentage of group variability in a particular characteristic that can be attributed to genetic factors.

Hertz (Hz): The measure of sound wave frequency as cycles per second.

Heuristics: A method of problem solving characterized by quick and easy search procedures similar to rules of thumb.

Higher-order conditioning: Classical conditioning, a neutral stimulus becomes a conditioned stimulus after it is paired with another conditioned stimulus (rather than with the original <br> unconditioned stimulus).

Hindbrain: The part of the brain situated immediately above the spinal cord that contains the brain stem and cerebellum.

Hippocampus: A structure of the limbic system that plays a key role in the formation and storage of memories.

Histogram: The graph of a frequency distribution.

Homeostasis: The maintenance of biological equilibrium, or balance, within the body.

Hormones: Substances secreted by the glands of the endocrine system that travel in the bloodstream and affect bodily organs, psychological functions, and development.

Humanistic perspective (humanism): A psychological view that emphasizes personal freedom, choice, and self-actualization.

Hypnosis: A condition of enhanced suggestibility in which some people are able to experience imagined situations as if they were real.

Hypnotic susceptibility scale: A set of induction procedures and test questions that enable researchers to measure a person's responsiveness to hypnotic suggestions.

Hypochondriasis: A somatoform disorder characterized by an overreaction to physical symptoms and a conviction that one has or is on the verge of a serious illness.

Hypothalamus: A forebrain structure located below the thalamus and above the pituitary gland that controls autonomic and hormonal processes and plays a major role in many aspects of motivation and emotional behaviour.

Hypothesis: A tentative explanation or a prediction about some phenomenon.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

I

Id: An aspect of Freud’s tri-partheid personality theory; the primitive and unconscious part of the personality that contains the instincts.

Illusions: Incorrect perceptions based on false perceptual hypotheses that often result from constancies that do not apply to the stimuli in question.

Imaginal thought: A form of thinking that uses images that can be from any sense modality.

Implicit memory: When memory influences our behaviour without conscious awareness.

Implicit prejudice: Prejudice that is hidden from public view, either intentionally or because the person is not aware that they are prejudiced.

Imprinting: A sudden, biologically primed form of attachment seen in some species.

Inattentional blindness: Failure of unattended stimuli to register in consciousness.

Incentive: An environmental stimulus or condition that motivates behaviour.

Incremental theorist: An individual who believes that people's characteristics are changeable, not fixed.

Incubation: A phenomenon in which the solution to a problem suddenly appears in consciousness after a problem solver has stopped thinking about it for a while.

Independent variable: In an experiment, the factor that is manipulated by the researcher.

Individualism: A cultural orientation, characteristic of many Western nations, that favours the achievement of individual over group goals; self-identity is based primarily on one's own <br> attributes and achievements (compare with collectivism).

Inductive reasoning: Reasoning that proceeds from a set of specific facts to a general conclusion or principle.

Indulgent parents: Caregivers who have warm and caring relationships with their children but do not provide much guidance and discipline.

Infantile amnesia: An inability to remember personal experiences from the first few years of our lives.

Inferential statistics: Probability based statistics that tell us how confident we can be in drawing conclusions or inferences about a population based on findings obtained from a sample.

Informational social influence: Following the opinions or behaviour of other people because we believe that they have accurate knowledge and that what they are doing is "right."

Informed consent: The principle that prior to agreeing to participate in research, a person should be fully informed about the procedures, the benefits, the risks involved, the right to withdraw <br> at any time without penalty, and matters of confidentiality and privacy.

Insanity defence: In the USA a legal decision that a defendant was so severely impaired at the time a crime was committed that he or she was incapable of appreciating the wrongfulness of the act or controlling his or her behaviour.

Insight: Gestalt psychology, the sudden perception of a useful relation or solution to a problem; in psychoanalysis, the conscious awareness of unconscious dynamics that underlie psychological <br> problems.

Insomnia: A sleep disorder involving chronic difficulty in falling asleep, staying asleep, or experiencing restful sleep.

Instinct: An inherited characteristic, common to all members of a species, that automatically produces a particular response when the organism is exposed to a particular stimulus.

Instinctive drift: The tendency for instinctive behaviours to override a conditioning procedure, thus making it difficult to create or maintain a conditioned response.

Instrumental behaviours: Behaviours that are directed at achieving specific goals or performing specific tasks.

Intelligence: ability to acquire knowledge, to think and reason effectively, and to deal adaptively with the environment.

Intelligence quotient (IQ): Originally defined as mental age (MA) divided by chronological age (CA) multiplied by 100 (IQ - [MA/CA] * 100); an IQ of 100 indicates that an individual is average for his or her age group. IQ scores today are based on norms derived from people of various ages.

Inter-rater or inter-judge reliability: The extent to which different observers or scorers agree in their scoring of a particular test or observed behaviour.

Internal consistency: extent to which items within a psychological test correlate with one another, indicating that they are measuring a common characteristic.

Internal-external locus of control: Rotter's theory, a generalized expectancy that one's outcomes are under personal versus external control.

Internal validity: The degree to which an experiment produces clear causal conclusions; internal validity is high when there is no confounding of variables.

Interneurons: that are neither sensory nor motor neurons but that perform associative or integrative functions within the nervous system.

Interpersonal therapy: A form of brief therapy that focuses on the client's interpersonal problems and seeks to develop new interpersonal skills.

Interpretation (in psychoanalysis): A statement made by the analyst that is intended to promote insight in the client.

Intrinsic motivation: The motivation to perform a task simply because one finds it interesting or enjoyable for its own sake.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

J

James-Lange theory: A theory of emotion that proposed that emotional experience is based on a person's perception of her or his bodily responses.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W| X | Y | Z

K

Kin selection: The view that organisms are most likely to help others with whom they share the most genes—namely, their offspring and genetic relatives.

Kinesthesis: The body sense that provides feedback on the position and movements of our body parts.

Knowledge-acquisition components: In Sternberg's triarchic model of intelligence, the mental capabilities that allow us to learn from our experiences, store information in memory, and combine new insights with previously acquired information.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

L

Language: A system of symbols and rules for combining them that can produce an infinite number of possible messages and meanings.

Language acquisition device (LAD): In Chomsky's theory, an innate, biologically based mechanism that facilitates the learning of language.

Language acquisition support system (LASS): The social learning opportunities involved in learning a language.

Latent learning: Learning that occurs in the absence of reinforcement but is not displayed until reinforcement is later introduced into the situation.

Lateralization: The degree of localization of a function in either the right or the left cerebral hemisphere.

Law of effect: Thorndike's concept that a response followed by satisfying consequences will become more likely to occur, whereas a response followed by unsatisfying consequences will become less likely to occur.

Learned helplessness theory: A theory of depression maintaining that if people are unable to control life events, they develop a state of helplessness that leads to depressive symptoms.

Learning: A relatively enduring change in an organism's behaviour or performance capabilities that occurs as a result of experience.

Lens: The transparent structure behind the pupil that changes its shape to focus images on the retina.

Leptin: A hormone secreted by fat cells that decreases general appetite.

Levels of processing: The concept that the more deeply we process information, the better it will be remembered.

Limbic system: A group of sub-cortical structures, including the hippocampus and amygdala, that are involved in organizing many goal-directed and emotional behaviours.

Linguistic relativity hypothesis: The idea, suggested by Whorf, that people's language determines the ways in which they perceive and think about their world.

Longitudinal design: A research approach in which the same people are repeatedly tested as they grow older.

Long-term memory: Our vast library of more durable stored memories.

Long-term potentiation: An enduring increase in synaptic strength that occurs after a neural circuit is rapidly stimulated.

Lowballing: A manipulation technique in which a persuader gets you to commit to some action and then, before you actually perform the behaviour, they increase the "cost" of that same behaviour.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

M

Magnetic resonance imaging (MRI): A brain-scanning procedure that produces a highly detailed image of living tissue based on the tissue's response to a magnetic field; can be used to study both structure and, in the case of functional MRI (fMRI), brain functions as they occur.

Maintenance rehearsal: The simple rote repetition of information.

Major depression: A mood disorder characterized by intense depression that interferes markedly with functioning.

Mania: A state of intense emotional and behavioural excitement in which a person feels very optimistic and energized.

Mastery-approach goals: Goals related to the desire to master a task and learn new knowledge and skills.

Mastery-avoidance goals: Goals that reflect a fear of not performing up to one's own standards.

Mastery goals: Achievement goals that focus on the desire to master a task and learn new knowledge or skills.

Matching effect: In romantic relationships, the tendency for partners to have a similar level of physical attractiveness.

Maturation: A genetically programmed biological process that governs our growth.

Mean: A statistic that represents the arithmetic average of a set of scores.

Means-ends analysis: A heuristic problem solving device in which people first define a sub-goal that they hope to achieve (an "end"), compare that sub-goal with their present state of knowledge, and, if there is a discrepancy between them, try to find the means to reduce the difference.

Measures of central tendency: Statistics that describe a distribution (a set of data) in terms of a single number that is in some way "typical" of the distribution as a whole.

Measures of variability: Statistics that provide information about the spread of scores in a distribution.

Median: In a set of data, the point that divides the distribution in half when the individual scores are arranged in order from lowest to highest.

Medulla: A brain stem structure that controls vital functions, including heartbeat and respiration.

Melatonin: A hormone, secreted by the pineal gland, that has a relaxing effect on the body and promotes a readiness for sleep.

Memory: The processes that allow us to record, store, and later retrieve experiences and information.

Memory codes: Mental representations of some type of information or stimulus.

Memory consolidation: The creation and binding together of neural codes that allow information to be transferred from working memory into long-term memory.

Menstrual synchrony: The tendency for some women who live together or are close friends over time to become more similar to one another in the timing of their menstrual cycles.

Mental image: A representation of a stimulus that originates inside your brain, rather than from external sensory input.

Mental representations: Cognitive representations of the world, including images, ideas, concepts, and principles, that are the foundations of thinking and problem solving.

Mental set: The tendency to stick to problem-solving strategies or solutions that have worked in the past.

Mere exposure effect: The tendency to evaluate a stimulus more favourably after repeated exposure to it.

Meta-analysis: A statistical procedure for combining the results of different studies that examine the same topic.

Metabolism: The rate of energy expenditure by the body.

Metacognition: Your awareness and understanding of your own cognitive abilities.

Metacomponents: In Sternberg's triarchic model of intelligence, the higher-level intellectual abilities used to plan and regulate task performance.

Method of loci: A memory aid in which pieces of information (e.g., items in a list) are each associated with a mental image of a different physical location.

Midbrain: Brain structures above the hindbrain that are involved in sensory and motor functions and in attention and states of consciousness.

Mind-body dualism: The philosophical position that the mind is a non-physical entity that is not subject to physical laws and therefore cannot be reduced to physical processes; body and mind are <br> separate entities.

Minnesota Multiphasic Personality Inventory-2 (MMPI-2): A widely used personality test whose items were developed using the empirical approach of comparing various kinds of psychiatric patients with a non-psychiatric sample.

Misinformation effect: The distortion of a memory by misleading post event information.

Mnemonic device: A strategy or technique that aids memory.

Mnemonist (memorist): A person who displays extraordinary memory <br> skills.

Mode: A statistic that represents the most frequently occurring score in a distribution of data.

Monism: A philosophical position that mental events are reducible to physical events in the brain, so that mind and body are one and the same.

Monocular depth cues: Cues that require only one eye; these include linear perspective, decreasing size, height in the horizontal plane, texture, clarity, light and shadow, motion parallax, and interposition.

Mood-congruent recall: The tendency to recall information or events that are congruent with our current mood.

Mood disorders: Psychological disorders whose core conditions involve maladaptive mood states, such as depression or mania.

Morpheme: The smallest unit of meaning in a given language; English morphemes include whole words, prefixes, and suffixes. There are over 100,000 English morphemes.

Motivation: The process that influences the direction, persistence, and vigour of goal-directed behaviour.

Motivational climate: The achievement context created by adults. In an ego-involving climate, performers are compared with one another and urged to compete to be the best; those who perform best get special attention. In a mastery-involving climate, effort, enjoyment of the activity, and personal improvement are emphasized and rewarded.

Motivational interviewing: A reatment approach that avoids confrontation and leads clients to their own realization of a problem and increases their motivation to change.

Motor cortex: The cortical area in the rear portion of the frontal lobes that controls voluntary movements on the opposite sides of the body.

Motoric thought: Mental representations of motor movements, such as throwing an object.

Motor neurons: Specialized neurons that carry neural messages from the brain and spinal cord to the muscles and glands.

Multimodal treatments: Substance-abuse interventions that combine a number of treatments, such as aversion therapy and coping skills training.

Myelin sheath: A fatty insulating substance on the axon of some neurons that increases the speed of neural transmission.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

N

Narcolepsy: Asleep disorder that involves extreme daytime sleepiness and sudden, uncontrollable sleep attacks during waking hours.

Naturalistic observation: A method in which the researcher observes behaviour in a natural setting and tries to avoid influencing the participants being observed.

Natural selection: The evolutionary process through which characteristics that increase the likelihood of survival and reproduction are preserved in the gene pool and thereby become more <br> common in a species over time.

Need for achievement: The desire to accomplish tasks and attain standards of excellence.

Need for positive self-regard: In Rogers's personality theory, the psychological need to feel positively about oneself that underlies self-enhancement behaviours.

Negative correlation: A relation between two variables in which higher scores on one variable are associated with lower scores on the other variable.

Negative reinforcement: The process whereby a response is strengthened by the subsequent removal of an aversive stimulus.

Negative symptoms: Schizophrenic symptoms that reflect a lack of normal reactions, such as emotions, speech, or social behaviours.

Neglectful parents: Caregivers who provide neither warmth nor rules or guidance.

Neoanalytic theorists: Former followers of Freud, such as Adler and Jung, who developed their own psychodynamic theories that generally de-emphasized psychosexual factors in favour of social ones and gave increased emphasis to ego functioning.

NEO-PI: An objective personality test that measures the Big Five personality factors.

Nerve deafness: Hearing loss caused by damage to the cochlear receptor cells or to the auditory nerve.

Neural network (connectionist) model: States that each concept stored in memory is represented by a unique pattern of distributed and simultaneously activated nodes that process information in <br> parallel; also known as a parallel distributed processing model.

Neural plasticity: The ability of neurons to modify their structure and function in response to experiential factors or injury.

Neural stem cells: Immature "uncommitted" cells that have the potential to mature into any type of neuron or glial cell needed by the brain.

Neurogenesis: The production of new neurons in the nervous system, sometimes to replace neurons that have died or been damaged.

Neuromodulators: Any substance that modifies or modulates the activities of the postsynaptic neuron.

Neurons: Nerve cells that constitute the basic building blocks of the nervous system.

Neurotic anxiety: In psychoanalytic theory, a state of anxiety that arises when impulses from the id threaten to break through into awareness or behaviour.

Neurotransmitters: Chemical substances that are released from the axons of one neuron, travel across the synaptic space, and bind to specially keyed receptors in another neuron, where they produce a chemical reaction that is either excitatory or inhibitory.

Night terrors: A disorder in which a sleeper—often feeling a strong sense of dread or danger—becomes aroused to a near panic state.

Normal curve: A symmetrical bell-shaped curve that represents a theoretical distribution of scores in the population.

Normal distribution: A frequency distribution in the shape of a symmetrical or bell-shaped curve that satisfies certain mathematical conditions deduced from the theory of probability.

Normative social influence: Conformity motivated by gaining social acceptance and avoiding social rejection.

Norm of reciprocity: The tendency to respond in kind when other people treat us well or poorly.

Norms (cultural or group): Rules (often unwritten) that specify what behaviour is acceptable and expected for members of a particular culture or group.

Norms (test) : Test scores derived from a relevant sample used to evaluate individuals' scores.

Null hypothesis: The hypothesis that any observed differences between samples on the variable(s) of interest are due to chance (i.e., in an experiment, the hypothesis that the independent variable had no effect on the dependent variable).<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

O

Object permanence: The recognition that an object continues to exist even when it no longer can be seen.

Object relations theories: The view that people form images or mental representations of themselves and other people as a result of early experiences with caregivers.

Observational learning: Learning through observing the behaviour of a model.

Obsession: An unwanted and disturbing thought or image that invades consciousness and is very difficult to control.

Oedipus complex: The theory that a male child experiences erotic feelings toward his mother, desires to possess her sexually, and views his father as a rival.

Olfaction: The sense of smell.

Olfactory bulb: A forebrain structure that receives input from the receptors for the sense of smell.

Openness: Tin psychotherapy this refers to the client's willingness to become personally invested in the process of therapy that predicts favourable therapeutic outcomes.

Operant conditioning: A type of learning in which behaviour is modified by its consequences, such as by reinforcement and punishment.

Operant discrimination: An operant response occurs when a particular antecedent stimulus is present but not when another antecedent stimulus is present.

Operant extinction: Occurs when the absence of reinforcement for a previously reinforced response causes that response to weaken and eventually stop.

Operant generalization: An operant response occurs to a new antecedent stimulus that is similar to the original antecedent stimulus.

Operational definition: Defining a concept or variable in terms of the specific procedures used to produce or measure it.

Opiates: A category of drugs consisting of opium and drugs derived from it, such as morphine, codeine, and heroin.

Optic nerve: The bundle of ganglion cell axons that carries information from the visual receptors to the visual area of the thalamus.

Organ of Corti: Structures embedded in the basilar membrane that contain the hair cell receptors for sound.

Outcome bias: Occurs when an intelligence test score underestimates a person's true intellectual ability.

Overconfidence: The pervasive tendency to overestimate one's degree of knowledge and predictive ability.

Overlearning: Continued rehearsal past the point of initial learning that significantly improves performance on memory tasks.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

P

Pain disorder: Somatoform disorder in which the person's complaints of pain cannot be accounted for in terms of degree of physical damage.

Panic disorder: An anxiety disorder characterized by unpredictable panic attacks and a pervasive fear that another will occur; may also result in agoraphobia.

Parallel distributed processing (PDP) model: A computer model in which each item in memory is represented by a particular pattern of distributed yet interconnected nodes that are activated <br> simultaneously (i.e., that operate in parallel); also known as a neural network model.

Paranoid schizophrenia: A schizophrenic disorder marked by delusional thinking and suspiciousness.

Parasympathetic nervous system: The branch of the autonomic nervous system that slows down bodily processes to conserve energy and reduce arousal.

Paraventricular nucleus (PVN): A cluster of neurons in the hypothalamus packed with receptor sites for transmitters that stimulate or reduce appetite.

Partial (intermittent) reinforcement: A reinforcement schedule in which only a portion of the responses of a particular type are followed by a reinforcer.

Passionate love: form of love that involves intense emotional arousal and yearning for one's partner.

Pearson product-moment correlation coefficient: A statistic that reflects the direction and strength of the relation between two variables; it can range in magnitude from +1.00 to -1.00.

Perception: The process of organizing stimulus input and giving it meaning.

Perceptual constancies: ability to recognize stimulus characteristics (e.g. size, color, and so on) under varying conditions.

Perceptual schemas: Representations that contain the essential features of an object of perception.

Perceptual set: A readiness to perceive a stimulus in a particular way based on expectations, motives, emotions, or beliefs.

Performance components: In Sternberg's triarchic model of intelligence, the specific mental processes used to perform a task.

Peripheral nervous system: All of the neurons that connect the central nervous system with the sensory receptors, the muscles, and the glands.

Peripheral route to persuasion: Occurs when people do not scrutinize a message but are influenced mostly by other factors such as a speaker's attractiveness or a message's emotional appeal.

Personal constructs: In George Kelly's personality theory, the cognitive categories used to sort events and make comparisons among people and events.

Personality: Those biologically and environmentally determined characteristics within the person that account for distinctive and relatively enduring patterns of thinking, feeling, and acting.

Personality disorder: A chronic, inflexible, maladaptive pattern of perceiving, thinking, and behaving that seriously impairs an individual's ability to function in social or other settings.

Personality traits: Relatively stable cognitive, emotional, and behavioural characteristics that help establish people's individual identities.

Personal unconscious: According to Jung, those aspects of the unconscious that arise from the individual's life experiences.

Phenomenology: A philosophical approach that focuses on immediate subjective experience.

Phenotype: The observable characteristics produced by one's genetic endowment.

Pheromones: Chemical signals found in natural body scents.

Phobias: Strong and irrational fears of particular objects or circumstances.

Phoneme: The smallest unit of speech sound in a language that can signal a difference in meaning. English has 40 phonemes.

Photopigments: Protein molecules within the rods and cones whose chemical reactions when absorbing light result in the generation of nerve impulses.

Placebo: An inactive or inert substance.

Placebo control group: A control group that receives an intervention that is assumed to have no therapeutic value.

Placebo effect: A change in behaviour that occurs because of the expectation or belief that one is receiving a treatment.

Place theory of pitch perception: States that sound frequencies are coded in terms of the portion of the basilar membrane where the fluid wave in the cochlea peaks; this theory accounts for perception of frequencies above 4,000 hertz.

Pleasure principle: The drive for instant need gratification that is characteristic of the id.

Polygenic transmission: A number of genes working together to create a particular phenotypic characteristic.

Polygraph: A research and clinical instrument that measures a wide array of physiological responses.

Pons: A brain stem structure having sensory and motor tracts whose functions are involved in sleep and dreaming.

Population: In a survey, the entire set of individuals about whom we wish to draw a conclusion.

Positive correlation: A relation between two variables in which higher scores on one variable are associated with higher scores on the other variable.

Positive psychology movement: A view that emphasizes the study of human strengths, fulfilment, and optimal living.

Positive reinforcement: A response is strengthened by the subsequent presentation of a reinforcing reward.

Positive symptoms: Schizophrenic symptoms such as delusions, hallucinations, and disordered speech and thinking.

Positron emission tomography (PET) scan: A procedure that provides a visual display of the absorption of a radioactive substance by neurons, indicating how actively they are involved as the brain performs a task.

Post-conventional moral reasoning: According to Kohlberg, the stage at which moral judgments are based on a system of internalized, well-thought-out moral principles.

Posttraumatic stress disorder (PTSD) : A pattern of distressing symptoms, consisting of instrusive thoughts, avoidance and hyper-arousal that recur after a traumatic experience; for example, flashbacks, nightmares, insomnia and anxiety responses.

Pragmatics: A knowledge of the practical aspects of using language, such as how our choice of words depends on the social context.

Pre-conventional moral reasoning: According to Kohlberg, the stage at which moral judgments are based on anticipated punishments or rewards.

Predictive bias: Occurs when an intelligence test successfully predicts criterion measures (for example, school or job performance) for some groups but not for others.

Prefrontal cortex: The area of the frontal lobe just behind the eyes and forehead that is involved in the executive functions of planning, self-awareness, and responsibility.

Prejudice: A negative attitude toward people based on their membership in a group.

Preoperational stage: In Piaget's theory, the stage of cognitive development in which children represent the world symbolically through words and mental images but do not yet understand basic <br> mental operations or rules.

Preparedness: The notion that, through evolution, animals have become biologically predisposed to learn some associations more readily than other associations.

Primacy effect: In impression formation, our tendency to attach more importance to the initial information that we learn about a person.

Primary appraisal: The initial appraisal of a situation as benign, irrelevant, or threatening; a perception of the severity of demands.

Primary reinforcer: A positive reinforcer that satisfies a biological need, such as food or water.

Priming: Occurs when exposure to a stimulus influences how you subsequently respond to that same or another stimulus; in long-term memory, refers to the activation of one concept by another.

Proactive interference: Occurs when material learned in the past interferes with the recall of newer material.

Problem-focused coping: Coping strategies that involve direct attempts to confront and master a stressful situation.

Problem-solving dream models: The view that dreams can help us find creative solutions to our problems and conflicts because they are not constrained by reality.

Problem-solving schemas: Step-by-step scripts for selecting information and solving specialized classes of problems.

Procedural (nondeclarative) memory:Memory that is reflected in learned skills and actions.

Projective tests: Tests, such as the Rorschach and the Thematic Apperception Test, that present ambiguous stimuli to the subject; the responses are assumed to be based on a projection of internal <br> characteristics of the person onto the stimuli.

Proposition: A statement that expresses an idea.

Propositional thought: A thought that expresses an idea in linguistic form, as when we seem to hear or say a sentence in our mind.

Prospective memory: Remembering to perform an activity in the future.

Protective factors: Environmental or personal resources that help people fare better in the face of stress.

Prototype: The most typical and familiar member of a class that defines a concept.

Proximodistal principle: The tendency for physical development to begin along the innermost parts of the body and continue toward the outermost parts.

Psychoactive drugs: Chemicals that affect mental processes and behaviour by temporarily changing conscious awareness of reality

Psychoanalysis: A psychological theory, originally developed by Freud, that emphasizes internal and primarily unconscious causes of behaviour.

Psychodynamic behaviour therapy: An integration of psychoanalysis and behaviour therapy.

Psychodynamic perspective: psychological perspective that focuses on how personality processes, including unconscious impulses, defences, and conflicts, influence behaviour.

Psychogenic amnesia: An extensive but selective memory loss that occurs after a traumatic event.

Psychogenic fugue (also called dissociative fugue): A dissociative phenomenon in which a person loses all sense of personal identity to the extent that they wander to another place and establish a new identity.

Psycholinguistics: The scientific field that studies psychological aspects of language.

Psychological test: Any given method for measuring individual differences related to some psychological construct, based on a sample of relevant behaviour obtained under standardized conditions.

Psychology: The scientific study of mind and behaviour.

Psychometrics: The statistical study of psychological tests; for example, the psychometric approach to intelligence focuses on the number and nature of abilities that define intelligence.

Psychophysics: The study of relations between the physical characteristics of stimuli and the sensory experiences they evoke.

Psychosexual stages: Stages of development in which psychic energy is focused on certain body parts. The major childhood stages are the oral, anal, and phallic stages; experiences during these stages are assumed to shape personality development.

Psychosocial stages: A sequence of eight developmental stages proposed by Erikson, each of which involves a different "crisis" (i.e., conflict) over how we view ourselves in relation to other people and the world.

Psychosurgery: Surgical procedures, such as lobotomy or cingulotomy, in which brain tissue involved in a behaviour disorder is removed or lesioned.

Puberty: A period of rapid biological maturation in which the person becomes capable of sexual reproduction.

Punishment: A response is weakened by an aversive outcome that follows it.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Q

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

R

Random assignment: A procedure in which each participant has an equal likelihood of being assigned to any one group within an experiment.

Randomized clinical trial: A research design that involves the random assignment of clients having specific problems to an experimental (therapy) group or to a control condition so as to draw sound causal conclusions about the therapy's efficacy.

Random sampling: In survey research, a method of choosing a sample in which each member of the population has an equal probability of being included in the sample.

Range: A statistic that represents the difference between the highest and the lowest scores in a distribution.

Rational-theoretical approach: An approach to test construction in which test items are made up on the basis of a theorist's conception of a construct.

Reaction range: The genetically influenced limits within which environmental factors can exert their effects on an organism.

Realistic conflict theory: Maintains that competition for limited resources fosters prejudice.

Reality principle: The ego's tendency to take reality factors into account and to act in a rational fashion in need satisfaction.

Receptor sites: Protein molecules on neurons' dendrites or soma that are specially shaped to accommodate a specific neurotransmitter molecule.

Reciprocal determinism: Bandura's model of two-way causal relations between the person, behaviour, and the environment.

Reflexes: Automatic, inborn behaviours triggered by specific stimuli.

Regression (in psychoanalytic theory): A defence mechanism in which a person retreats to an earlier stage of development in response to stress.

Reinforcement: A response is strengthened by an outcome that follows it.

Relapse prevention: A treatment approach designed to teach coping skills, increase self-efficacy, and counter the abstinence violation effect, thus reducing the likelihood of relapse.

Reliability (in psychological testing): the consistency with which a measure assesses a given characteristic or different observers agree on a given score.

Remote behaviour sampling: A method of collecting samples of behaviour from respondents as they live their daily lives.

REM sleep: A recurring sleep stage characterized by rapid eye movements, increased physiological arousal, paralysis of the voluntary muscles, and a high rate of dreaming.

REM-sleep behaviour disorder (RBD): A sleep disorder in which the loss of muscle tone that causes normal REM-sleep paralysis is absent, thereby enabling sleepers to move about, sometimes <br> Violently, and seemingly act out their dreams.

Replication: The process of repeating a study to determine whether the original findings can be duplicated.

Representativeness heuristic: A rule of thumb in estimating the probability that an object or event belongs to a certain category based on the extent to which it represents a prototype of that category.

Representative sample: A sample that accurately reflects the important characteristics of the population.

Repression: The basic defence mechanism that actively keeps anxiety-arousing material in the unconscious.

Resistance: Largely unconscious manoeuvres that protect clients from dealing with anxiety-arousing material in therapy.

Response cost (also known as negative punishment and punishment by removal): A type of punishment in which an operant response is weakened by the subsequent removal of a stimulus that was not the cause of the original response (e.g., a mobile phone is taken away from a child who is misbehaving in order to gain attention).

Response prevention: The prevention of escape or avoidance responses during exposure to an anxiety-arousing conditioned stimulus so that extinction can occur.

Resting potential: The voltage differential between the inside and outside of a neuron (about -70 mv) caused by the unequal distribution of ions inside the neuron's membrane and outside in the <br> fluid surrounding the neuron when the neuron is at rest.

Restoration model: The theory that sleep acts to recharge our run-down bodies and allow us to recover from physical and mental fatigue.

Reticular formation: A structure extending from the hindbrain into the lower forebrain that plays a central role in consciousness, sleep, and attention, in part by alerting and activating higher brain centres (ascending portion) and by selectively blocking some inputs to higher regions in the brain (descending portion).

Retina: The light-sensitive tissue at the back of the eye that contains the visual receptors.

Retrieval: The process of accessing information in long-term memory.

Retrieval cue: Any stimulus, whether internal or external, that triggers the activation of information stored in long-term memory.

Retroactive interference: When newly acquired information interferes with the ability to recall information learned at an earlier time.

Retrograde amnesia:Memory loss for events that occurred prior to the onset of the amnesia.

Reuptake: The process whereby transmitter substances are taken back into the presynaptic neuron so that they do not continue to stimulate postsynaptic neurons.

Rods: Photoreceptors in the retina that function under low levels of illumination and do not give rise to colour sensations.

Role Construct Repertory (Rep) Test: The technique developed by personality psychologist Kelly to assess people's personal constructs by asking them to describe the ways in which people resemble and differ from one another.

Rorschach test: A projective technique involving the interpretation of inkblots that is used by psychodynamic psychologists to assess perceptual and psychodynamic aspects of personality.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

S

Sample: In a survey, a subset of individuals drawn from the population.

Scatterplot: A graph commonly used to examine correlational data; each pair of scores on variable X and variable Y is plotted as a single point.

Schema: A mental framework; an organized pattern of thought about some aspect of the world, such as a class of people, events, situations, or objects.

Schizophrenia: A psychotic disorder involving serious impairments of attention, thought, language, emotion, and behaviour.

Script: A specialized schema that represents a sequence of events (e.g., "going to the movies") that unfolds in a regular, almost standardized order.

Seasonal affective disorder (SAD): A disorder in which depressive symptoms appear or worsen during certain seasons of the year (most typically, fall and winter) and then improve during the other seasons.

Secondary appraisal: One's judgment of the adequacy of personal resources needed to cope with a stressor.

Secondary (conditioned) reinforcer: stimulus that acquires reinforcing qualities by being associated with a primary reinforcer.

Seeking social support: Turning to others for assistance or emotional support in times of stress.

Selective attention: A cognitive process that focuses awareness on some stimuli to the exclusion of others.

Self: In Rogers's theory, an organized, consistent set of perceptions and beliefs about oneself.

Self-actualization: In humanistic theories, an inborn tendency to strive toward the realization of one's full potential.

Self-consistency: An absence of conflict among self- perceptions.

Self-determination theory: A humanistic theory formulated by Deci and Ryan that focuses on three fundamental psychological needs: competence, autonomy, and relatedness.

Self-efficacy: The conviction that we can perform the behaviours necessary to produce a desired outcome.

Self-enhancement: Processes whereby one enhances positive self-regard.

Self-esteem: How positively or negatively we feel about ourselves.

Self-fulfilling prophecy: Occurs when people's erroneous expectations lead them to act in a way that brings about the expected behaviours, thereby confirming the original <br> impression.

Self-instructional training: A cognitive coping approach of giving adaptive self-instructions to oneself at crucial phases of the coping process.

Self-monitoring: A personality trait that reflects people's tendencies to regulate their social behaviour in accord with situational cues, as opposed to internal values, attitudes, and <br> needs.

Self-perception theory: Maintains that we make inferences about our own attitudes by observing how we behave.

Self-reinforcement processes: Administered rewards and punishments that are contingent on meeting certain standards for behaviour that are an important basis for the self-regulation of behaviour.

Self-relatedness: Relating to psychotherapy this refers to a client's ability to be flexible, to change, to listen carefully to the therapist and to constructively use what is learned in therapy.

Self-serving bias: The tendency to make relatively more personal attributions for success and situational attributions for failures.

Self-verification: The tendency to try to verify or validate one's existing self-concept (i.e., to satisfy congruence needs).

Semantic memory: General factual knowledge about the world and language, including memory for words and concepts.

Semantics: The linguistic rules for connecting symbols in language to what they represent.

Senile dementia:Dementia (a gradual loss of cognitive abilities due to normal brain deterioration) that begins after age 65.

Sensation: The process by which stimuli are detected, transduced into nerve impulses, and sent to the brain.

Sensitive period: An optimal age range for certain experiences, but if those experiences occur at another time, normal development will still be possible (compare with critical period).

Sensorimotor stage: In Piaget's theory, the stage of cognitive development in which children understand their world primarily through sensory experiences and physical (motor) interactions with objects.

Sensory adaptation: sensitivity to an unchanging stimulus with the passage of time as sensory neurons habituate to the stimulation.

Sensory memory:Memory processes that retain incoming sensory information just long enough for it to be recognized.

Sensory neurons: Specialized neurons that carry messages from the sense organs to the spinal cord and brain.

Sensory prosthetic device: A device for providing sensory input that can, to some extent, substitute for what cannot be supplied by the person's own sensory receptors.

Separation anxiety: Distress experienced by infants when they are separated from a primary caregiver, peaking between ages 12 and 16 months and disappearing between ages 2 and 3 years.

Sequential design: A research approach that involves repeatedly testing several age cohorts as they grow older.

Serial position effect: The finding that recall is influenced by an item's position in a series.

Set point: biologically determined standard around which body weight (or more specifically, our fat mass) is regulated.

Sex-typing: Treating other people differently based on whether they are female or male.

Sexual dysfunction: Chronic, impaired sexual functioning that distresses a person.

Sexual orientation: A person's emotional and erotic preference for partners of a particular sex.

Sexual response cycle: A physiological response to sexual stimulation that involves stages of excitement, plateau, orgasm, and resolution.

Sexual strategies theory: Maintains that sex differences in mating strategies and mating preferences reflect inherited biological predispositions that have been shaped in women and men over the course of evolution.

Shaping: An operant conditioning procedure in which reinforcement begins with a behaviour that the organism can already perform and then is made contingent on behaviours that increasingly approximate the final desired behaviour.

Shared environment: The environmental conditions shared by a family or other social group over a period of time.

Short-term memory: A memory store that temporarily holds a limited amount of information.

Signal detection theory: A theory that assumes that stimulus detection is not based on a fixed absolute threshold but rather is affected by rewards, punishments, expectations, and motivational <br> factors.

Situation-focused intervention: Prevention efforts that focus on altering environmental conditions that are known to promote the development of psychological disorders.

Skinner box: An experimental chamber in which animals learn to perform operant responses, such as pressing a bar or pecking, so that the learning process can be studied.

Sleep apnoea: A disorder characterized by a repeated cycle in which the sleeper stops breathing, momentarily awakens gasping for air, and then returns to sleep.

Slow-wave sleep: Stages 3 and 4 of sleep, in which the EEG pattern shows large, slow brain waves called delta waves.

Social causation hypothesis: The proposition that attributes the higher prevalence of schizophrenia in low-income people to the greater stress they experience.

Social clock: The set of cultural norms concerning the optimal age range during which work, marriage, parenthood, and other major life experiences should occur.

Social-cognitive theories (of hypnosis): The view that hypnotic experiences occur because people are highly motivated to assume the role of being hypnotized; the person develops a readiness to <br> perceive hypnotic experiences as real and involuntary.

Social-cognitive theory: A cognitive behavioural approach to personality developed by Bandura and Mischel that emphasizes the role of social learning, cognitive processes, and self-regulation.

Social comparison: The act of comparing one's personal attributes, abilities, and opinions with those of other people.

Social compensation: Working harder when in a group than when alone to compensate for other members' lower output.

Social constructivism: The view that people construct their reality and beliefs through their cognitions.

Social desirability bias: A tendency to self-report or behave in a way that presents oneself in a favourable light, rather than respond as one truly feels.

Social drift hypothesis: The notion that as people develop schizophrenia, their personal and occupational functioning deteriorates, so that they drift down the socioeconomic ladder.

Social exchange theory: A theory proposing that a social relationship can best be described in terms of exchanges of rewards and costs between the two partners.

Social identity theory: Maintains that prejudice stems from a need to enhance our self-esteem.

Socialization: The process by which culture is transmitted to new members and internalized by them.

Social learning theory: Bandura's former name for social-cognitive theory.

Social loafing: The tendency for people to expend less individual effort when working collectively in a group than when working alone.

Social norms: Shared expectations about how people should think, feel, and behave.

Social phobia: An excessive and inappropriate fear of social situations in which a person might be evaluated and possibly embarrassed.

Social role: A set of norms that characterizes how people in a given social position (e.g., "the mother," "the police officer") ought to behave.

Social skills training: A technique in which a client learns more effective social behaviours by observing and imitating a skillful model.

Social structure theory: Maintains that men and women behave differently, such as expressing different mate preferences, because society directs them into different social and economic roles.

Socio-cultural perspective: A view that emphasizes the role of culture and the social environment in understanding commonalities and differences in human behaviour.

Somatic nervous system: The branch of the peripheral nervous system that provides input from the sensory receptors and output to the voluntary muscles of the body.

Somatic relaxation training: A means of voluntarily reducing or preventing high arousal using muscle relaxation.

Somatic sensory cortex: Cortical strips in the front portions of the parietal lobes that receive sensory input from the opposite side of the body.

Somatoform disorder: A disorder in which a person complains of bodily symptoms that cannot be accounted for in terms of actual physical damage or dysfunction.

Source confusion: The tendency to recall something or recognize it as familiar but to forget where it was encountered. Also called source monitoring error.

Specificity question: The ultimate question of psychotherapy research: "Which types of therapy administered by which kinds of therapists to which kinds of clients having which kinds of problems <br> produce which kinds of effects?"

Specific phobia: An irrational and excessive fear of specific objects or situations that pose little or no actual threat.

Speech segmentation: The task of perceiving where each word within a spoken sentence begins and ends.

Splitting: A tendency, often found in people with borderline personality disorder , to not integrate the positive and negative aspects of another's behaviour into a coherent cognitive representation of the person.

Spontaneous recovery (in classical conditioning): The reappearance of a previously extinguished conditioned response after a period of time has passed following extinction.

Spontaneous remission: Improvements in symptoms in the absence of any therapeutic interventions.

Standard deviation (SD) : A measure of variability that takes into account how much each score in a distribution deviates from the average score. Statistically, the square root of the variance of a set of scores.

Standardisation: In psychological testing, refers to (1) creating a standard set of procedures for administering a test or making observations and (2) deriving norms with which an individual's <br> performance can be compared.

State-dependent memory: The enhanced ability to retrieve information when our internal state at the time of retrieval matches our original state during learning.

Static testing: The traditional approach to testing, in which the test is administered under highly standardized conditions.

Statistical significance: In research, a term that means it is unlikely that a particular finding occurred by chance alone. Psychologists typically consider a result to be statistically significant only if it could have occurred by chance less than 5 times in 100.

Stereotype: A generalized belief about a group or category of people.

Stereotype threat: The anxiety created by the perceived possibility that one's behaviour or performance will confirm a negative stereotype about one's group.

Stimulants: Drugs that stimulate neural activity, resulting in a state of excitement or aroused euphoria.

Stimulus control: The occurrence of an operant behaviour in response to a discriminative stimulus.

Stimulus generalization: A conditioned response occurs to stimuli other than the original conditioned stimulus, based on the similarity of these stimuli to the conditioned stimulus.

Stimulus hierarchy: In systematic desensitization, the creation of a series of anxiety-arousing stimuli that are ranked in terms of the amount of anxiety they evoke.

Storage: The retention of information in memory over time.

Stranger anxiety: Distress over contact with strangers that typically develops in the first year of infancy and dissipates in the second year.

Strange situation: A standardized procedure used to determine the type of emotional attachment between an infant and a caregiver.

Strategic pluralism: The notion that multiple, even contradictory, behavioural strategies (for example, introversion and extraversion) might be adaptive in certain environments and would <br> therefore be maintained through natural selection.

Stress: A term variously used to refer to (1) situations that place strong demands on an organism, (2) the cognitive, physiological, and behavioural responses to such situations, and (3) the ongoing <br> transaction between individuals and demanding situations.

Stress-induced analgesia: A reduction in pain sensitivity that occurs when endorphins are released under stressful conditions.

Stressors: Situations that place demands on organisms that tax or exceed their resources.

Stress response: The pattern of cognitive, physiological, and behavioural reactions to demands that exceed a person's resources.

Stroboscopic movement: The illusory movement produced when adjacent lights are illuminated and extinguished at specific time intervals.

Structuralism: An early German school of psychology established by Wundt that attempted to study the structure of the mind by breaking it down into its basic components, which were believed to be sensations.

Structured interview: A standardized interview protocol in which only pre-specified questions are asked.

Sub-goal analysis: A problem-solving heuristic in which people attack a large problem by formulating sub-goals, or intermediate steps toward a solution.

Subjective well-being: Happiness; the overall degree of satisfaction with one's life.

Sublimation: The channelling of unacceptable impulses into socially accepted behaviours, as when aggressive drives are expressed in violent sports.

Subliminal stimuli: Weak stimuli below the perceptual threshold that are not consciously perceived.

Substance dependence: A maladaptive pattern of substance use that causes a person significant distress or substantially impairs that person's life; substance dependence is diagnosed as occurring "with physiological dependence" if drug tolerance or withdrawal symptoms have developed.

Suicide: The intentional taking of one's own life.

Superego: In psychonalysis, the moral arm of the personality that internalizes the standards and values of society and serves as the person's conscience.

Suprachiasmatic nuclei (SCN): The brain's master ‘biological clock’ that regulates most circadian rhythms. It is located in the hypothalamus.

Surface structure: A linguistic term for the words and organization of a spoken or written sentence. Two sentences may have quite different surface structure but still mean the same thing.

Survey research: A method using questionnaires or interviews to obtain information about many people.

Sympathetic nervous system: The branch of the autonomic nervous system that has an arousal function on the body's internal organs, speeding up bodily processes and mobilizing the body.

Synaptic space: The microscopic space between the axons of one neuron and the dendrites or cell body of another over which the nerve impulse is transmitted.

Synaptic vesicles: Chambers within the axon that contain the neurotransmitter substance.

Synesthesia: A condition in which stimuli are experienced not only in the normal sensory modality but in others as well.

Syntax: The rules for the combination of symbols within a given language.

Systematic desensitization: A procedure used to eliminate anxiety using counter-conditioning, in which a new response that is incompatible with anxiety is conditioned to the anxiety-arousing conditioned stimulus.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W| X | Y | Z

T

Tardive dyskinesia: An irreversible motor disorder that can occur as a side effect of certain antipsychotic drugs.

Taste buds: Chemical receptors for taste in the tongue and in the roof and back of the mouth that are sensitive to the qualities of sweet, sour, salty, and bitter.

Temperament: A biologically based general style of reacting emotionally and behaviourally to the environment.

Teratogens: Environmental (non-genetic) agents that cause abnormal prenatal development.

Test-retest reliability: a measure of the correlation between the scores of the same people on the same test given on two different occasions

Thalamus: A major sensory integration and relay centre in the forebrain, sometimes referred to as the brain's sensory switchboard.

THC (tetrahydrocannabinol): The major active ingredient in marijuana.

Theory: A set of formal statements that explains how and why certain events or phenomena are related to one another.

Theory of cognitive dissonance: States that people strive to maintain consistency in their beliefs and actions and that inconsistency creates dissonance (i.e., unpleasant arousal) that motivates people to restore balance by changing their cognitions or behaviour.

Theory of mind: A person's beliefs about the "mind" and the ability to understand other people's mental states.

Theory of planned behaviour: Maintains that our intention to engage in a behaviour is strongest when we have a positive attitude toward that behaviour, when subjective norms (our perceptions of what other people think we should do) support our attitudes, and when we believe that the behaviour is under our control.

Threat: In Rogers's theory, any experience we have that is inconsistent with our self-concept, including our perceptions of our own behaviour. Threat evokes anxiety.

Three-stratum theory of cognitive abilities: A model of intelligence based on factor analysis that contains three hierarchical levels of ability, from specific skills to a general intellectual (g) factor.

Tip-of-the-tongue (TOT) state: The experience of being unable to recall something but feeling that you are on the verge of remembering it.

Token economy: A procedure in which desirable behaviours are reinforced with tokens or points that can later be redeemed for other reinforcers.

Tolerance: A condition in which increasingly larger doses of a drug are required to produce the same level of bodily responses; caused by the body's compensatory responses, which counter the effects of the drug.

Top-down processing: Perceptual processing in which existing knowledge, concepts, ideas, or expectations are applied in order to make sense of incoming stimulation.

Transduction: The conversion of one form of energy into another; in sensation, the process whereby physical stimuli are translated into nerve impulses.

Transference: The psychoanalytic phenomenon in which a client responds irrationally to the analyst as if the latter were an important person from the client's past who plays a significant role in the client's dynamics.

Transtheoretical model: A model of behaviour change that includes the phases of precontemplation, contemplation, preparation, action, maintenance, and termination.

Trauma-dissociation theory: Accounts for the development of dissociative identity disorder as a defence against severe childhood abuse or trauma.

Triangular theory of love: Maintains that various types of love result from different combinations of three core factors: intimacy, commitment, and passion.

Triarchic theory of intelligence: Sternberg's theory of intelligence that distinguishes between analytical, practical, and creative forms of mental ability.

Twin study: A research method in behaviour genetics in which identical (monozygotic) and fraternal (dizygotic) twins are compared on some characteristic; this method is particularly informative if the twins have been raised in different environments.

2 * 2 achievement goal theory: A model of motivation in which each person can be described in terms of an achievement motivation profile involving four types of goals: mastery-approach, ego-approach, mastery-avoidance, and ego-avoidance goals.

Two-factor theory of avoidance learning: Maintains that avoidance learning first involves the classical conditioning of fear, followed by learning operant responses that avoid an anticipated aversive stimulus and thus are reinforced by anxiety reduction.

Two-factor theory of emotion: Schachter's theory stating that intensity of physiological arousal determines perceived intensity of emotion, whereas appraisal of environmental cues tells us which <br> emotion we are experiencing.

Type A behaviour pattern: A sense of time urgency, competitiveness, pressured behaviour, and hostility that could be a risk factor in coronary heart disease.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

U

Unconditional positive regard: A communicated attitude of total and unconditional acceptance of another person that conveys the person's intrinsic worth.

Unconditioned response (UCR) : A response (usually reflexive or innate) that is elicited by a specific stimulus (the unconditioned stimulus) without prior learning.

Unconditioned stimulus (UCS) :A stimulus that elicits a particular reflexive or innate response (the unconditioned response) without prior learning.

Undifferentiated schizophrenia: A residual category of schizophrenia for people who have the characteristic positive and negative symptoms of schizophrenia but do not meet the specific criteria for the paranoid, disorganized, or catatonic subtypes.

Unobtrusive measures: Techniques for measuring behaviour in which participants are kept unaware that their behaviour is being recorded or observed.

Upward comparison: Seeing oneself as worse off than the standard for comparison.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

V

Validity: The extent to which a test actually measures what it is supposed to measure; the degree to which a diagnostic system's categories contain the core features of the behaviour disorders and <br> permit differentiation among the disorders.

Variable: Any characteristic of an organism or situation that can vary.

Variable-interval (VI) schedule: A reinforcement schedule in which reinforcement follows the first response of a particular type that occurs after an average but variable time interval following the last reinforced response.

Variable-ratio (VR) schedule: A reinforcement schedule in which reinforcement is based on an average but variable number of responses of a particular type.

Variance: A statistic that measures the average of the squared deviation scores about the mean of a distribution.

Vestibular sense: the sense of body orientation, or equilibrium.

Virtual reality (VR): Computer-produced virtual environments that immerse an individual and produce experiences similar to those of a corresponding real environment.

Visual acuity: the ability to see fine detail.

Visual agnosia: disorder in which an individual is unable to visually recognize objects.

Vulnerability factors: Situational or physical factors that increase susceptibility to the negative impact of stressful events.

Vulnerability-stress model: Explains behaviour disorders as resulting from predisposing biological or psychological vulnerability factors that are triggered by a stressor.<br>

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

W

Weber's law: States that to perceive a difference between two stimuli, the stimuli must differ by a constant percentage or ratio.

Wernicke's area: An area of the left temporal lobe that is involved in speech comprehension.

Wisdom: A system of knowledge about the meaning and conduct of life.

Wish fulfilment: In Freudian theory, the partial or complete satisfaction of a psychological need through dreaming or waking fantasy.

Withdrawal: The occurrence of compensatory responses after drug use is discontinued, causing the person to experience physiological reactions opposite to those that had been produced by the drug.

Working memory: A mental workspace that temporarily stores information, actively processes it, and supports other cognitive functions.<br>

X

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Y

Young-Helmholtz trichromatic theory: The colour vision theory stating that there are three types of colour receptors in the retina - one for red, one for blue, and one for green —and that combinations of activation of these receptors can produce perception of any hue in the visible spectrum.

Z

Zone of proximal development: The difference between what a child can do independently and what the child can do with assistance from adults or more advanced peers.

Zygote: The fertilized egg.