echolalia: a condition often found in autisticchildren and catatonic schizophrenics, whereby individuals demonstrate a pathological repetition of other’s words, either immediately or delayed for hours or days.

efficacy: the effectiveness of a treatment used in medicine or psychotherapy.

ego: (Latin for ‘I’) in psychoanalysis, the part of personality that serves to mediate between id and superego, by directing instinctual drives and urges into appropriate channels.

egocentricity: evident at the preoperational stage, whereby a young child is unable to take the perspective of another person. Piaget’s ‘three mountains’ experiment is a test of egocentricity, as children are unable to see how the ‘mountains’ would look to a child at a different location.

elaborative rehearsal: the active processing of items to improve memory, through a variety of methods, from focusing on sensory characteristics (visual appearance, sound) to an emphasis on the semantic content (meaning) of information.

electroconvulsive shock treatment (ECT): the use of passing small amounts of electric current through the brain, inducing a convulsion or epileptic seizure, as an effective treatment for severe depression.

electroencephalograph (EEG): a non-invasive method of recording the electrical activity of the brain, by fixing electrodes to the scalp. 

emancipation (psychological): The step by step development of the personality of a self-reliant mature individual. All good education guides towards mature self-reliance and  self-realisation.

emotion: an pattern of intense changes in physiological arousal, behavior, cognitive processes and environmental influences that are described in subjective terms such as happiness, fear or anger.

emotion-focused coping: aims to manage the negative effects of stress on the individual, through changing an emotional response.

emotional development: the development of a full range of emotions from sad to happy to angry, and learning to deal with them appropriately.

emotional state: the state of a person's emotions (especially with regard to pleasure or dejection).

empathy: the ability to understand another person's perceptions and feelings; cited by Rogers as a condition for growth.

empirical data: information derived from measurements made in "real life" situations (eg, field data).

encoding: changing sensory input into a mental representation in the memorysystem.

endocrine glands: glands which secrete hormones directly into the bloodstream.

endocrinologist: a specialist of the endocrine glands and hormone systems of the body. ie pituitary gland, adrenal gland, testes.

endogenous:caused by factors within the body or mind or arising from internal structural or functional causes.

endogenous pacemakers: inherited mechanisms important for the regulation of biological rhythms, particularly in the absence of external cues. The principal endogenous pacemaker in mammals is a small group of cells in the hypothalamus, known as the suprachiasmatic nucleus (SCN), which regulates the production of melatonin in the pineal gland.

endorphins: a neuropeptide which plays an important role in pain and mood states.

environmental stressors (aggressive behaviour): elements of the environment that give rise to anti-social behavior, by increasing arousal which subsequently may produce negative emotions and aggressive behavior. For instance, high temperatures, intense levels of noise, and crowding can produce high levels of aggression.

episodic memory: long-term memories for personal experiences and the contexts in which they occur.

equilibration: in Piaget's theory of cognitive development, maintaining balance between the environment and the mental structures (schemas) which we use to represent that environment.

Erikson (1902-1994): psychoanalyst and proponent of developmental psychology. Proposed eight stages of psychosocial development from birth to death, for instance identity vs. role confusion.

ergonomics: the study of the 'fit' between human operators and their workplace, which can be used to design working environments that maximise user efficiency.

estimator variables: in witness testimony, variables that affect the accuracy of witness testimony, that the justice system has little control over, including weather and amount of time witness was at the scene

ethical guidelines: prescriptive guidance (e.g. clear guidelines published by the BPS) on the conduct of psychologists in research and practice, to oversee what is acceptable within the pursuit of a specific goal, including informed consent, right to withdraw and debriefing.

ethical hedonism: the view that individuals engage in moral behaviour, such as altruism, because it provides some personal advantage.

ethics: a major branch of philosophy.  The study of principles relating to right and wrong conduct; Morality; The standards that govern the conduct of a person, especially a member of a profession.

ethnocentrism: the practice of researching or theorising from the perspective of a particular ethnic, national or cultural group.  

euphoria: a feeling of happiness, confidence, or well-being sometimes exaggerated in mood disorders as mania.

evolutionary psychology: the application of evolutionary ideas, including the importance of behavioural and mental adaptiveness over millions of years, to help explain human behaviour.

excitatory: that tends to excite or causes excitation.

existential therapies: see humanistic therapies.

exogenous zeitgebers ('time givers'): external events that help regulate biological rhythms, for instance, light and social stimuli (see also endogenous pacemakers).

extraneous variables: variables that make possible an alternative explanation of results; an uncontrolled variable.

expectancy/incentive approaches: in the study of motivation, these approaches explore incentives that produce goal-directed behaviour.

experiment: a test under controlled conditions made to either demonstrate a known truth, examine the validity of a hypothesis, or determine the efficacy of something previously untried.

experimental methods: systematically manipulate the independent variable to determine the effect upon the dependent variable. Extraneous variables that may influence the outcome of the experiment are rigorously controlled.

experimental group: participants in an experiment who receive the independent variable. The control group serves as a comparison group.

experimental psychology: is a field of psychology that typically involves laboratory research in basic areas of the discipline.

experimenter effects: when an experimenters behavior or characteristics influence participants, through subtle cues or signals, that can affect the performance or response of subjects in the experiment.

explicit memory: requires a conscious attempt to recall memory.

external validity: an extent to which research results can be generalised beyond the specific situation studied.

extinction: when the conditioned responses ceases to be produced, with the absence of a reinforcer or unconditioned stimulus.

extroversion: a dimension of personality, characterised by sociability, the tendency to engage in conversation with others and impulsiveness. Extroversion can be measured on the Introversion-Extroversion scale of the EPI (Eysenck Personality Inventory).

eyewitness testimony: the study of the accuracy of memory following an accident or crime, and an exploration of the types of errors commonly made.

Eysenck Personality Inventory (EPI): a personality test designed to measure the traits of extroversion and neuroticism.