Glossary of Psychological Terms

Definitions of terms used in psychology, psychometric testing and occupational assessment, organised alphabetically.

Echoic store

A brief sensory memory, lasting a second or two after an auditory stimulus, that preserves an initial impression of a sound before it fades or is processed further — the auditory equivalent of an iconic store for vision.

Echolalia

The meaningless, involuntary repetition of words or phrases someone else has just spoken; typically a sign of psychosis, autism spectrum conditions, or serious brain damage.

Echolocation

A technique for locating objects by emitting sound waves and interpreting their echoes as they bounce back — the basis of sonar and of navigation in bats and whales. Blind people sometimes use a related technique, often without realising it, tapping a stick to interpret the echoes it produces.

ECT

An abbreviation for electroconvulsive therapy — see that entry.

Educational psychology

The branch of psychology concerned with the principles and methods of teaching, learning and education more broadly, including assessment, motivation and individual differences among learners.

EEG

An abbreviation for electroencephalograph — see that entry.

Effective stimulus

A stimulus capable of producing a response when it reaches an appropriate sense receptor — for instance, light shone toward the eye, as opposed to light shone where it cannot be detected.

Efferent

Describing the transmission of nerve impulses outward from the brain and central nervous system to the muscles and glands. Contrast with afferent, which describes impulses travelling inward toward the brain.

Efficacy

A term used in social psychology (often as “self-efficacy”) for how effective a person feels in influencing matters important to them — a belief closely linked to motivation, persistence and coping under stress.

Ego

Literally “the I”: the conscious awareness of oneself. In Freud's structural model of the mind, the ego is the part of the personality closest to external reality, mediating between the unconscious, pleasure-seeking drives of the id and the internalised restrictions of the superego. Neurosis, in this view, arises when the ego cannot maintain a workable balance between these competing pressures.

Ego defence

Also called ego defence mechanisms: the range of unconscious strategies the ego uses when id impulses conflict with each other, when id impulses conflict with superego values, or when the ego faces an external threat. Though sometimes treated as a single fixed trait, the concept actually covers several distinct types of reaction, elaborated particularly by Anna Freud. See also: defence mechanism.

Ego ideal

In psychoanalysis, the component of the superego representing identification with admired and loved parents or parental figures, embodying the standards a person aspires to meet.

Ego strength

A person's capacity to maintain a stable, functioning ego — able to manage internal conflict and external demands without succumbing to emotional disturbance or maladjustment.

Egocentricity

Literally “self-centred”: an interest in oneself to the exclusion of others. In Piaget's developmental theory, the term carries no judgement of selfishness, but describes a stage lasting until around age 7 or 8 in which a child cannot adopt another person's perceptual or conceptual perspective — describing how an object looks only from their own vantage point, for instance, or assuming a foreigner remains “foreign” even in their own country, while never applying that label to themselves. This stage ends once the child achieves reciprocity, though traces of egocentric thinking can persist into adulthood.

Elaborated code

British sociolinguist Basil Bernstein's term for an articulate communication style using full, explicit phrasing to convey precise and complex ideas, with emotional and intellectual content clearly distinguished — said to be typical of middle-class parent-child communication. Contrasted with restricted code.

Elaborative rehearsal

A memory strategy that connects new information to existing knowledge, or to other new material, in order to make it more meaningful and memorable. Contrast with rote learning, simple mechanical repetition without meaningful connection.

Electroconvulsive therapy

A treatment, used mainly for severe depression, in which a brief electrical current is passed through the brain to induce a controlled seizure. The exact mechanism by which it eases depressive symptoms remains unclear, and its long-term effects are debated. Modern practice uses sedation and muscle relaxants to minimise physical risk; the technique remains controversial, with critics regarding it as a crude intervention despite continued clinical use in severe, treatment-resistant cases.

Electroencephalograph

A device that records the brain's ongoing electrical activity, typically via electrodes attached to the scalp, producing a graph of brain waves at different frequencies (such as alpha, beta and delta rhythms).

Emotion

A complex state involving diffuse physical changes, strong subjective feeling, and a behavioural impulse directed toward a specific goal. Precisely identifying and labelling particular emotions involves a substantial element of social learning, and both the categories and their expression vary considerably across cultures and historical periods.

Empathy

The capacity to understand another person's feelings, or to accurately imagine their perspective, without actually experiencing those feelings oneself — generally treated as more of a cognitive than a purely emotional capacity. Compare with sympathy, which involves sharing in or being moved by another's feelings.

Empirical

Describing a finding based on direct experience, observation or experiment, rather than on theory or reasoning alone; the basis of experimental science.

Empiricism

The philosophical position that personal experience is the primary or sole source of genuine knowledge. In psychology, particularly influential in debates over perception — for instance, whether the perception of depth and space is learned through experience rather than being innate.

Encephalitis

Inflammation of the brain, usually caused by infection, which can sometimes result in lasting personality change and an apparent reduction in intellectual functioning.

Encoding

In information-processing models of memory, the process of converting incoming information into a form that can be stored and later retrieved (decoded) by the brain.

Encounter group

A therapeutic or personal-growth group that uses sensitivity training — structured interpersonal exercises intended to increase self-awareness and openness with others.

Endogamy

The practice or social rule of choosing marriage partners from within one's own social, ethnic or kinship group. Contrasted with exogamy.

Endorphins

A group of chemicals produced naturally by the brain and pituitary gland that have opiate-like effects, reducing pain and enhancing feelings of pleasure or wellbeing; first identified in the 1970s and since linked to phenomena such as “runner's high.”

Engineering psychology

The American term for ergonomics — the study of how people interact with machines, tools and work environments.

Engram

A hypothetical physical trace of a memory in brain tissue. Many psychologists have long assumed that learning produces some lasting physical change in the brain, though the precise nature of such changes has historically been difficult to observe directly.

Entrapment

In social psychology, the process by which a person's commitment to a course of action escalates in order to justify their initial investment in it, leaving them feeling increasingly unable to break free even as costs mount — a phenomenon closely derived from cognitive dissonance theory.

Enuresis

Involuntary release of urine, such as bed-wetting in children, usually attributed to emotional stress or developmental factors rather than an underlying physical cause.

Environmental-stress theory

A sociological account of what psychologists would generally call neurosis, attributing it to the distorting effect of a person's particular environment on behavioural tendencies that are, in principle, common to everyone.

Epigenesis

A biological theory of embryonic development emphasising the influence of environment: the interaction between the developing embryo and its surroundings produces new properties not present in the original fertilised egg (zygote). In psychology, particularly in the work of Erik Erikson, the term describes a fixed sequence of developmental stages that must each be worked through to achieve psychological maturity.

Epilepsy

A neurological condition involving disturbances in the brain's electrical activity. In its severe form (grand mal), it can produce violent convulsions and prolonged loss of consciousness; in its milder form (petit mal), only momentary dizziness or a brief lapse in awareness. Anticonvulsant medication can often control seizures, though the underlying causes of epilepsy — historically known as the “falling sickness” — remain incompletely understood.

Epinephrine

See adrenalin, the term more commonly used outside North America for the same hormone.

Epiphenomenon

In the philosophy of mind, an event that accompanies another event without exerting any causal influence on it — a concept much discussed in debates over whether consciousness itself has any causal role in behaviour.

Episodic memory

Memory for personally experienced events, including the context in which they occurred — either general knowledge of what an experience is typically like, or memory of a specific occurrence. Compare with semantic memory, which is memory for general facts and concepts independent of when or where they were learned.

Epistemology

The branch of philosophy concerned with the nature, origins, limits and justification of knowledge — the study of how, and whether, we can truly know what we claim to know.

Equal-status contact

A principle, considered important by social scientists in reducing prejudice, holding that contact between members of different groups is most effective at breaking down bias when the parties involved hold genuinely equal social status, rather than an unequal relationship that can reinforce existing stereotypes.

Ergonomics

The study of the interaction between people and their working environment, especially their relationship to tools, machines and equipment, drawing on psychology alongside anatomy and physiology.

Erikson, Erik (1902-1979)

A psychoanalyst usually classified as neo-Freudian for his emphasis on ego psychology and his central preoccupation with identity. In Childhood and Society, Erikson proposed an epigenetic sequence of eight psychosocial stages of development, each built around a crucial task that must be navigated to progress toward maturity — with adolescence, the period of identity formation, considered especially pivotal. His interest in identity crises extended to studies of historical figures, notably in Young Man Luther, helping to establish the field of psychobiography, and his work broadened developmental psychology's traditional focus on early childhood to include adolescence and the full life course.

Eros

In Greek mythology, the god of love; adopted by Freud to symbolise the libido, or the fundamental life-preserving drive. Always contrasted with Thanatos, the death instinct.

ESP

An abbreviation for extrasensory perception — the claimed ability to acquire information through means other than the recognised senses, such as telepathy or precognition. A central subject of parapsychology, though it lacks reliable scientific support.

Estrogen

See oestrogen, the more common spelling outside North America for this hormone.

Ethnic identity

Either (1) the particular ethnic group a person identifies with, or is identified by others as belonging to, or (2) the extent to which that ethnic group forms a significant part of a person's overall sense of identity.

Ethnocentrism

The tendency to view one's own group, especially one's ethnic group, as inherently superior to others. Like egocentricity at the individual level, it involves difficulty stepping outside one's own group's frame of reference to genuinely see the world from another group's point of view.

Ethnography

The systematic study of the history, customs, myths, traditions and culture of particular ethnic or social groups, which may be defined by shared ancestry, nationality, religion, language, or some combination of these.

Ethnology

The comparative analysis of the behaviour patterns documented across different ethnic groups by ethnography, seeking broader patterns and explanations.

Ethnomethodology

An approach associated with American sociologist Harold Garfinkel, focused on examining people's everyday lives and the largely unquestioned, taken-for-granted assumptions they hold about the social world.

Ethology

Originally the study of ethical systems, but now understood as the comparative study of animal behaviour in its natural habitat, with particular attention to innate behaviours that appear regardless of an individual animal's prior experience.

Etiology

See aetiology, an alternative spelling for the study of the causes of a disorder or disease.

Eugenics

A branch of applied genetics that seeks to improve the inherited characteristics of a species through selective breeding. When applied to human beings, its goals, values and methods raise serious ethical questions that have been debated since antiquity, and which were catastrophically abused in the twentieth century, permanently discrediting eugenics as a field of legitimate scientific or policy practice.

Euthanasia

The deliberate ending of a painful, terminal life in order to relieve suffering — sometimes called “mercy killing” — a practice that remains legally and ethically contested across jurisdictions.

Evoked potential

A measurable electrical discharge in the brain, detected via EEG, produced in direct response to the stimulation of a sense organ — closely related to the event-related potential used in cognitive neuroscience research.

Evolution

The gradual process of genetic change in populations of living things across generations, driven by natural selection: individuals best adapted to their environment in a given generation have the greatest chance of surviving and reproducing successfully, passing their traits on to the next generation. See also: Darwin, Charles, survival value.

Exchange theory

A framework for explaining relationships between two people (a dyad) in terms of the relative rewards and costs each person experiences from the relationship. Introduced to social psychology by John Thibaut and Harold Kelley, and to sociology by George Homans.

Exchange theory of friendship

A sociological application of exchange theory to friendship, using market-style language: people are seen as assessing their own social “worth” and seeking friends of comparable or greater worth to exchange companionship and support with.

Exhibitionism

A compulsion to expose oneself in public, whether in a literal physical sense or in a more metaphorical sense of seeking excessive attention.

Existential psychiatry

A movement rejecting the standard medical model for treating mental illness in favour of analysing and engaging with the disturbed individual's own conscious sense of self. The person is treated not as a patient to be cured but as an individual to be understood and supported toward greater self-understanding. See also: Laing, R. D.

Existential psychology

A school of thought holding that psychology's central task is to understand consciousness and the contents of the mind, using introspection — close attention to one's own immediate awareness — as its basic method. Though often presented as a growing contemporary emphasis, its roots trace back to Wilhelm Wundt in the nineteenth century.

Exogamy

The practice or rule of choosing marriage partners from outside one's own social or kinship group, involving both a biological dimension (outbreeding, reducing genetic relatedness between partners) and a cultural dimension (marrying outside a specific clan or religious group). Contrasted with endogamy.

Experiment

A controlled procedure, central to the scientific method, used to test a hypothesis by observing a phenomenon under conditions designed to isolate its cause. The general sequence runs from observation, to a question or problem, to a hypothesis, to a test of that hypothesis through experimentation, to analysis of results and, eventually, theory.

Experimental bias

The distorting effect on an experiment's outcome of an experimenter's conscious or unconscious attempts, however unintentional, to influence results toward a predicted direction — a pervasive concern given how often published experiments confirm their own hypotheses. See also: demand characteristics, double-blind technique, interviewer bias, Rosenthal effect, self-fulfilling prophecy.

Experimental design

Strictly, the specific plan for how an independent variable will be manipulated to test its effect on a dependent variable; more broadly, the term covers the entire procedure of an experiment, from selecting participants through to the statistical analysis of results.

Experimental group

In an experiment, the group of participants who are exposed to the variable under study (the experimental or independent variable) and whose behaviour is expected to be affected by it. Contrasted with the control group, which is not exposed to that variable.

Experimental neurosis

Disturbed, agitated behaviour observed in animals confronted with an unsolvable experimental problem. First identified by Pavlov, who rewarded a dog for salivating in response to a circle but not an ellipse, then gradually made the two shapes more similar until the dog could no longer distinguish them — at which point it broke into frenzied, disorganised behaviour. Whether this response is genuinely comparable to human neurosis remains a long-debated question among psychologists.

Experimental psychology

A methodological approach rather than a single subject area, spanning many fields of psychology — traditionally neuroscience, developmental psychology, sensation, perception, attention, consciousness, learning, memory, thinking and language, and more recently extending to motivation, emotion and social psychology. Its defining concern is using controlled experimental methods to uncover the processes underlying behaviour and cognition.

Experimental realism

A term used in social psychology for the goal of capturing the essential psychological elements of a real-life situation within an experiment, rather than attempting to reconstruct that real-life situation exactly (mundane realism). The Prisoner's Dilemma paradigm is a classic example.

Experimental variable

The technical name for the independent variable when it is directly manipulated by the experimenter; in practice, the two terms are often used interchangeably.

Explicit memory

The conscious, deliberate recollection of specific information or past experience — the form of memory most commonly disrupted in amnesia, as distinct from implicit memory, which can remain intact even when explicit recall is impaired.

Extended family

A family structure, defined somewhat differently across societies, that includes relatives more distant — genetically or geographically — than the nuclear family, such as grandparents, aunts, uncles and cousins living within the same household or close network.

Externalisation

A term used in several related ways: attributing one's own thoughts and feelings to some external cause; projecting one's inner states onto the external world; experiencing one's own mental processes as though they originate outside one's own mind (as in hallucination); or, developmentally, the gradual process throughout childhood of separating one's sense of self from the external world — what Freudian theory describes as ego formation.

Extinction

In experimental psychology, the weakening and eventual disappearance of a conditioned response, brought about either by repeatedly presenting the conditioned stimulus without the unconditioned stimulus, or by withholding reinforcement for the response.

Extrapunitive

Describing a characteristic pattern of responding to frustration with aggression directed outward, at the people or objects perceived as its cause. Contrast with intropunitive, in which frustration is turned inward against oneself.

Extraversion

In Carl Jung's theory, a fundamental personality dimension marked by openness, sociability and an outward-looking orientation toward the external world. Usually contrasted with introversion.

Extrinsic motivation

Engaging in an activity for the sake of an external reward or to avoid punishment, rather than for the inherent satisfaction of the activity itself. Always contrasted with intrinsic motivation. See also: functional autonomy.

Eye contact

The act of two people looking directly into each other's eyes — a behaviour studied by social scientists as a window into interpersonal distance, attention and relationship dynamics, both within a given culture and comparatively across different cultures.

Eyewitness testimony

A term from forensic psychology for the body of research on the factors — stress, the passing of time, leading questions, own-race bias and others — that influence how complete and accurate an eyewitness's account of an event turns out to be.

Eysenck, H. J. (1916-1997)

A leading British psychologist working within the behaviourist tradition, noted for his influential theories of personality (including his dimensions of extraversion-introversion and neuroticism-stability) and for developing widely used personality tests. He remained a controversial figure, particularly for his contributions to the fraught debate over race and IQ.