Dissociative identity disorder (DID) is a mental illness that involves the sufferer experiencing at least two clear identities or personality states, also called alters, each of which has a fairly consistent way of viewing and relating to the world. Some individuals with DID have been found to have personality states that have distinctly different ways of reacting, in terms of emotions, pulse, blood pressure, and blood flow to the brain. This disorder was formerly called multiple personality disorder (MPD) and is often colloquially referred to as split personality disorder. Statistics regarding this disorder indicate that the incidence of DID is about 3% of patients in psychiatric hospitals and is described as occurring in females nine times more often than in males. However, this female preponderance may be due to difficulty identifying the disorder in males. Also, disagreement among mental health professionals about how this illness appears clinically, and if DID even exists, adds to the difficulty of estimating how often it occurs.

Some professionals continue to be of the opinion that DID does not exist. The nature of this skepticism is sometimes due to questions about why many more individuals who have endured the stress of terrible abuse as young children do not develop the disorder, why more children are not diagnosed as having DID, and why some DID sufferers have no history of tremendous trauma. One explanation for what some believe to be these inconsistencies is that given the highly complex and unknown nature of the human brain and psyche, many of those whom one would expect to develop dissociative identity disorder are spared due to their resilience. Another concern about the diagnosis of DID involves having to rely on the traumatic memories of those who suffer from this disorder. That DID is significantly more often assessed in individuals in North America compared to the rest of the world, for the most part, leads some practitioners to believe that DID is a culture-based myth rather than a true disorder. As with many other mental health issues, symptoms of the same disorder in children look very different than symptoms in adults. Studies that verify the presence of DID using multiple resources add credibility to the diagnosis. Research on individuals with DID that have little to no media exposure to information on the illness lends further credibility to the reliability of the existence of this mental health condition.

Although there was a case study of DID as early as 1906, movies about DID first became well known in the United States since the 1950s. The 1953 movie The Three Faces of Eve tells the story of Chris Sizemore, a real-life woman with the disorder. She was thought to develop DID in reaction to witnessing several terrible accidents at a young age. That movie described three personalities that were successfully merged or integrated into one within one year. More accurately, the person depicted in that movie reportedly had to contend with 22 personalities that took more than 45 years to be able to coexist in a functional way. A television miniseries about DID was Sybil. The character of Sybil Dorsett portrayed the life story of Shirley Ardell Mason, who experienced severe physical, emotional, and sexual abuse that was inflicted by her mother. She was thought to develop 16 distinct identities. As with the diagnosis in general, the veracity of the story of Sybil remains a controversy, with claims that the illness in general, and Sybil specifically, is a hoax.

Dissociative Identity Disorder (DID) Facts

Dissociative identity disorder (DID), formerly called multiple personality disorder, is an illness that is characterized by the presence of at least two clear personality states, called alters, which may have different reactions, emotions, and body functioning.

How often DID occurs remains difficult to know due to disagreement among professionals about the existence of the diagnosis itself, its symptoms, and how to best assess the illness.

DID is diagnosed nine times more often in females than in males.

A history of severe abuse is thought to be associated with DID. DID has been portrayed in the media in productions like The Three Faces of Eve and Sybil.

Signs and symptoms of DID include memory lapses, blackouts, being often accused of lying, finding apparently strange items among one's possessions, having apparent strangers recognize them as someone else, feeling unreal, and feeling like more than one person.

As there is no specific diagnostic test for DID, mental health professionals perform a mental health interview, ruling out other mental disorders, and referring the client for medical evaluation to rule out a physical cause for symptoms.

Individuals with DID often also suffer from other mental illnesses, including posttraumatic stress disorder, borderline and other personality disorders, and conversion disorder.

People who may benefit either emotionally or legally from having DID sometimes pretend to have it, as with those who molest children, have antisocial personality disorder, or in cases of Munchausen's syndrome.

Some researchers are of the opinion that sex offenders who truly suffer from DID are best identified using a structured interview.

Psychotherapy is the mainstay of treatment of DID and usually involves helping individuals with DID improve their relationship with others, preventing crises, and to experience feelings they are not comfortable with having.

Eye movement desensitization and reprocessing (EMDR), a treatment method that integrates traumatic memories with the patient's own resources, is being increasingly used in the treatment of people with dissociative identity disorder.

Hypnosis is sometimes used to help people with DID learn more about their personality states in the hope of their gaining better control of those states.

Although medications can be helpful in managing emotional symptoms that sometimes occur with DID, caution is exercised when it is prescribed in order to avoid making the individual feel retraumatized by feeling controlled.

People with DID may have trouble keeping a job and maintaining relationships and are at risk for engaging in drug and alcohol abuse as well as hurting themselves and others.

What are causes and risk factors of dissociative identity disorder?

While there is no proven specific cause of DID, the prevailing psychological theory about how the condition develops is as a reaction to 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, 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.

What are the signs and symptoms of dissociative identity disorder?

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 traveled 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 recall, unrelated 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 as someone else;

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 like they are watching themselves move through life rather than living their own life;

feeling like more than one person.