What is dissociative identity disorder characterized by?

Dissociative identity disorder (DID), previously known as multiple personality disorder, is characterized by the presence of two or more distinct identities or personality states within a single individual. Each distinct identity may have its own name, age, history, and characteristics, each capable of taking control of the person's behavior at different times. This fragmentation of identity often arises as a coping mechanism in response to traumatic experiences, particularly during childhood.

The disorder is complex and involves significant disruptions in memory, identity, consciousness, and perception. While memory loss can occur in DID, it is specifically related to gaps in memory that are associated with the various identities, but that phenomenon does not define the disorder. DID's core feature is the existence of these multiple identities, which can be starkly different from one another. Such a core aspect is what fundamentally distinguishes DID from other mental health disorders.