psychological development Development of cognitive, emotional, intellectual, and social capabilities and functioning over the course of one’s life. It is the subject matter of the discipline of developmental psy¬ chology. In infancy, language is acquired, perception, emotion, and memory take shape, and learning and motor skills develop. In childhood, speech emerges, cognitive abilities advance from concrete to abstract operations, emotional responses become more sophisticated, and empathy and moral reasoning begin to be employed. Adolescence is a time of rapid emotional and intellectual growth, while adulthood is characterized by the maturing of all developmental processes.
psychological testing Use of tests to measure skill, knowledge, intel¬ ligence, capacities, or aptitudes and to make predictions about perfor¬ mance. Best known is the IQ test; other tests include achievement tests— designed to evaluate a student’s grade or performance level—and personality tests. The latter include both inventory-type (question-and- response) tests and projective tests such as the Rorschach (inkblot) and thematic apperception (picture-theme) tests, which are used by clinical psychologists and psychiatrists to help diagnose mental disorders and by psychotherapists and counselors to help assess their clients. Experimen¬ tal psychologists routinely devise tests to obtain data on perception, learn¬ ing, and motivation. Clinical neuropsychologists often use tests to assess cognitive functioning of people with brain injuries. See also experimental psychology; psychometrics.
psychological warfare Use of propaganda against an enemy, sup¬ ported by whatever military, economic, or political measures are required, and usually intended to demoralize an enemy or to win it over to a dif¬ ferent point of view. It has been carried on since ancient times. The con¬ quests of Genghis Khan were aided by expertly planted rumours about large numbers of ferocious Mongol horsemen in his army. Specialized units were a major part of the German and Allied forces in World War II and the U.S. armed forces in the Korean and Vietnam wars. Strategic psy¬ chological warfare is mass communications directed to a very large audi¬ ence or over a considerable expanse of territory; tactical psychological warfare implies a direct connection with combat operations (e.g., the sur¬ render demand). Consolidation psychological warfare consists of mes¬ sages distributed to the rear of one’s own advancing forces for the sake of protecting the line of communications, establishing military govern¬ ment, and carrying out administrative tasks within such a government.
psychology Scientific discipline that studies mental processes and behaviour in humans and other animals. Literally meaning “the study of the mind,” psychology focuses on both individual and group behaviour. Clinical psychology is concerned with the diagnosis and treatment of men¬ tal disorders. Other specialized fields of psychology include child psychol¬ ogy, educational psychology, sports psychology, social psychology, and comparative psychology. The issues studied by psychologists cover a wide spectrum, including learning, cognition, intelligence, motivation, emotion, perception, personality, and the extent to which individual differences are shaped by genetics or environment. The methods used in psychological research include observation, interviews, psychological testing, laboratory experimentation, and statistical analysis.
psychometrics Science of psychological measurement. Psychometri¬ cians design and administer psychological tests (see psychological testing).
both to generate empirical data on mental processes and to refine their understanding of measurement techniques and the statistical analysis of results. Major concerns include test reliability and validity and the norm- ing or standardization of results.
psychoneurosis See neurosis psychopathology See abnormal psychology
psychopharmacology Study of the effect of drugs on the mind and behaviour, particularly in the context of developing treatments for men¬ tal disorders. Major psychopharmacological advances in the 20th century include the development of tranquilizers, antidepressants, lithium carbon¬ ate (for bipolar disorder), certain stimulants (including amphetamines), and antipsychotic agents such as chlorpromazine (Thorazine), fluphenazine (Prolixin), and haloperidol (Haldol).
psychophysics Branch of psychology concerned with the effect of physical stimuli (such as sound waves) on mental processes. Psychophys¬ ics was established by Gustav Theodor Fechner in the mid-19th century, and since then its central inquiry has remained the quantitative relation between stimulus and sensation. A key tenet has been Weber's law. Psy¬ chophysical methods are used today in vision research and audiology, psy¬ chological testing, and commercial product comparisons (e.g., tobacco, perfume, and liquor).
psychosis \sI-'ko-s9s\ Serious mental derangement characterized by defective or lost contact with reality. The primary psychoses are schizo¬ phrenia and the delusional disorders (e.g., megalomania), but extreme cases of depression and bipolar disorder, substance-induced delirium, and certain varieties of dementia are also understood to share important fea¬ tures with the psychoses. The major symptoms, aside from delusions and hallucinations, are disorganized speech and behaviour and, often, mood disturbances. Treatment usually consists of medication and counseling in an institutional setting. Compare neurosis.
psychosomatic disorder Bodily ailment or symptom, caused by mental or emotional disturbance, in which psychological stresses adversely affect physiological (somatic) functioning to the point of dis¬ tress. Psychosomatic disorders may include hypertension, respiratory ail¬ ments, gastrointestinal disturbances, migraine and tension headaches, sexual dysfunctions, and dermatitis. Many patients with psychosomatic con¬ ditions respond to a combination of drug therapy and psychotherapy. See also HYPOCHONDRIASIS.
psychosurgery Treatment of psychosis or other mental disorders by means of brain surgery. The first such technique was the prefrontal lobotomy. Fairly common from the 1930s through the 1950s, lobotomy reduced neurotic symptoms such as agitation and aggressiveness but also left patients apathetic and with a limited range of emotions; it has since been largely replaced by the use of tranquilizing and antipsychotic drugs (see psychopharmacology). A form of psychosurgery developed more recently involves the placement of tiny lesions in specific areas of the brain and has little effect on intellectual function or quality of life; it has been used to treat obsessive-compulsive disorder and occasionally cases of severe psychosis.
psychotherapy Treatment of psychological, emotional, or behaviour disorders through interpersonal communications between the patient and a trained counselor or therapist. The goal of many modern individual and group therapies is to establish a central relationship of trust in which the client or patient can feel free to express personal thoughts and emotions and thus gain insight into his condition and generally share in the heal¬ ing power of words. Such therapies include psychoanalysis and its variants (see Alfred Adler; Carl Gustav Jung), client-centred or nondirective psycho¬ therapy, Gestalt therapy (see Gestalt psychology), play and art therapy, and general counseling. In contrast, behaviour therapy focuses on modifying behaviour by reinforcement techniques without concerning itself with internal states.
Ptah \'pta\ In Egyptian religion, the creator god. The patron of craftsmen, especially sculptors, Ptah was identified by the Greeks with Hephaestus, the divine blacksmith. He was represented as a man in mummy form, wearing a skullcap and a short, straight false beard. He was originally the local deity of Memphis, capital of Egypt from the 1st dynasty onward; the political importance of Memphis caused Ptah’s cult to spread across Egypt. With Sekhmet and Nefertem, he was one of the Memphite Triad of deities. See photograph on opposite page.