Quick GuideSchizophrenia: Symptoms, Types, Causes, Treatment

While there is no proven specific cause of DID, the prevailing psychological theory about how the condition usually develops is as a reaction to severe childhood trauma. Specifically, it is thought that one way that some individuals respond to being severely traumatized as a young child is to wall off altered states of consciousness, in other words to dissociate, those memories. When that reaction becomes extreme, DID may be the result. As with other mental disorders, having a family member with DID may be a risk factor, in that it indicates a potential vulnerability to developing the disorder but does not translate into the condition being literally hereditary.

Signs and symptoms of dissociative identity disorder include

• lapses in memory (dissociation), particularly of significant life events, like birthdays, weddings, or birth of a child;
• experiencing blackouts in time, resulting in finding oneself in places but not recalling how one got there;
• being frequently accused of lying when they do not believe they are lying (for example, being told of things they did but do not remember, not related to the influence of any drug or medical condition);
• finding items in one's possession but not recalling how those things were acquired;
• encountering people with whom one is unfamiliar but who seem to know them sometimes by another identity;
• being called names that are completely unlike their own name or nickname;
• finding items they have clearly written but are in handwriting other than their own;
• hearing voices inside their head that are not their own;
• not recognizing themselves in the mirror;
• feeling unreal (derealization);
• feeling detached from oneself, like they are watching themselves move through life rather than living their own life;
• feeling like more than one person.