Multiple personality

Multiple personality disorder may affect individuals who have suffered childhood trauma, usually of repeated emotional, physical and sexual abuse. It is perceived as the co-existence simultaneously in a single body of several (usually between 8 and 13) totally distinct and complex personalities. The control of the body "switches" from one personality to another, often without the individual being aware of the previous personality.

The alter personalities may have different physiological characteristics (brainwave patterns, immune status, left and right-handedness), behaviour patterns, and skills (including ability to speak foreign languages). An awareness that one alter personality has of another is referred to as co-consciousness; and the ability of one to influence the behaviour of another as co-presence. Common to many sufferers of MPD is an [inner self helper]

, apparently an inner spirit guide, which is not an alter personality as such but which knows and understands the individual's past, predicts future behaviour and advises (accurately) on therapy.

Conflicting attributes and subpersonalities are evidently present in everyone. Different situations call into activity endless alterations and recombinations of the elements of the self; and depending on conditions the various "selves" are fixed and perpetuated. Study of individuals in which [dissociative states]

are so extreme is hoped to shed light in general on the inner workings of the mind. There are links between dissociative states, hypnotic trance and epilepsy. The alter personalities appear to be related to different levels or states of consciousness produced by different emotional states, this being related to the state when particular behaviour patterns were learned. Some sources equate channelling (apparent contact with supernatural beings) with multiple personality, although in channelling there is a control lacked by the individual suffering from MPD.