A split personality refers to dissociative identity disorder (DID), a mental disorder where a person has two or more distinct personalities. The thoughts, actions, and behaviors of each personality may be completely different. Trauma often causes this condition, particularly during childhood.

What mental disorders have a split personality?

Dissociative Identity Disorder (Multiple Personality Disorder) A mental health condition, people with dissociative identity disorder (DID) have two or more separate personalities. These identities control a person's behavior at different times.

Are you born with split personality disorder?

Etiology of Dissociative Identity Disorder

Children are not born with a sense of a unified identity; it develops from many sources and experiences. In overwhelmed children, many parts of what should have blended together remain separate.