brain surgery on human patients intended to relieve severe and otherwise intractable mental or behavioral problems
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