At least two of these personalities repeatedly assert themselves to control the affected person's behavior. Each personality state has a distinct name, past, identity, and self-image.
Psychiatrists and psychologists use a handbook called the Diagnostic and Statistical Manual of Mental Disorders , fourth edition text revision or DSM-IV-TR , to diagnose mental disorders. In this handbook, DID is classified as a dissociative disorder. Other mental disorders in this category include depersonalization disorder ,dissociative fugue , and dissociative amnesia . It should be noted, however, that the nature of DID and even its existence is debated by psychiatrists and psychologists.