Multiple personality

A relatively rare disorder in which one's personality becomes so fragmented that two (or more) relatively independent subpersonalities emerge. The condition of multiple personality is an abnormality that is not to be confused with the pronounced changes in style, behavior, and reactivity shown by most normal persons as they move between different social situations and different social roles. The pathological condition is marked by circumstances in which these varied manifestations of self become so divided that the sense of underlying integrity is lost. Lay people often confuse multiple personality with schizophrenia, probably because of the persistent and erroneous use of the colloquialism "split personality" for schizophrenia (the "split" in schizophrenia is between affect and thought, not between "personalities").