a severe disturbance of mental activity manifested in impaired reflection of objective reality and pronounced deviations from normal behavior. The clinical picture includes marked disturbances of thinking, altered perception, delusions, hallucinations, severe agitation or pronounced psychomotor retardation, catatonic disorders, and inappropriate behavior. A psychotic state has a disorganizing effect on human activity. Psychoses occur against a background of hereditary predisposition (the most vivid example being schizophrenia), and may also arise due to psychogenic causes or organic brain damage.