Dissociative identity disorder (DID), previously known as multiple personality disorder (MPD), is a mental disorder characterized by at least two distinct and relatively enduring identities or dissociated personality states.
Dissociative disorders are mental disorders that involve experiencing a disconnection and lack of continuity between thoughts, memories, surroundings, actions and identity. People with dissociative disorders escape reality in ways that are involuntary and unhealthy and cause problems with functioning in everyday life.
Dissociative disorders usually develop as a reaction to trauma and help keep difficult memories at bay. Symptoms — ranging from amnesia to alternate identities — depend in part on the type of dissociative disorder you have. Times of stress can temporarily worsen symptoms, making them more obvious.
Treatment for dissociative disorders may include talk therapy (psychotherapy) and medication. Although treating dissociative disorders can be difficult, many people learn new ways of coping and lead healthy, productive lives.