Insatiable hunger; pathological overeating.The psychological drive to overeat is usually classified as a psychophysiologic disorder of the gastrointestinal system, although some regard it as a hysterical, or conversion, symptom. Regardless of the classification, the important fact is that in most cases bulimia is believed to be due to emotional factors. It may be a means of relieving stresses due to external situations or internal tensions, and is often interpreted as an unconscious attempt to recapture the feeling of security experienced early in life when food was received from the mother.An insatiable appetite may also have a number of symbolic meanings arising from unconscious sources. It may represent a hunger for affection, since love is so closely associated with being fed in infancy. It may be a substitute or a compensation for satisfactions presently denied, such as tenderness, sex, or attention. It may express hostile wishes, since chewing and swallowing are, in a sense, acts of destruction. Moreover, the resulting obesity may be an unconscious attempt to seek security in size and to clothe one’s self in an armor of fat against a threatening world.In some cases, according to psychoanalytic theory, the compulsive drive to consume food may stem from unresolved problems, such as emotional starvation, during the oral phase of psychosexual development when the mouth and its functions were the child’s basic source of satisfaction. Some analysts have also suggested that overeating may arise from an unconscious wish to become pregnant, a wish that may motivate men as well as women. In this view, eating and drinking are symbolic acts of fertilization, and obesity represents pregnancy.Ravenous appetites are also found among psychotic patients, especially schizophrenics who have regressed to primitive, infantile behavior. On the other hand, bulimia may be due to a number of organic disorders involving endocrine disturbances; it may also be caused by an inflammation affecting the hunger center in the hypothalamic region of the brain. Only a small minority of cases, however, are believed to be due to organic conditions. See OBESITY, HYPOTHALAMUS,CANALIZATION.