Dissociative identity disorder (DID), is a mental disorder on the dissociative spectrum characterized by at least two or more distinct and relatively enduring identities or dissociated personality states that alternately control a person's behavior.
DID reflects a failure to integrate various aspects of identity, memory and consciousness in a single multidimensional self. Usually, a primary identity carries the individual's given name and is passive, dependent, guilty and depressed. When in control, each personality state, or alter, may be experienced as if it has a distinct history, self-image and identity. The alters' characteristics—including name, reported age and gender, vocabulary, general knowledge, and predominant mood—contrast with those of the primary identity. Certain circumstances or stressors can cause a particular alter to emerge. The various identities may deny knowledge of one another, be critical of one another or appear to be in open conflict.
