Dissociative Identity Disorder

Clinical Description

• Formerly known as multiple personality disorder
• Defining feature is dissociation of personality
• Adoption of several new identities (as many as 100; may be just a few; average is 15)
• Identities display unique behaviors, voice, and postures

DSM-5 Criteria

• A. Disruption of identity characterized by two or more distinct personality states, which may be described in some cultures as an experience of possession.
  • The disruption of marked discontinuity in sense of self and sense of agency, accompanied by related alterations in:
  • affect, behavior, consciousness, memory, perception, cognition, and/or sensory-motor functioning.
  • These signs and symptoms may be observed by others or reported by the individual.
• B. Recurrent gaps in the recall of everyday events, important personal information, and/or traumatic events that are inconsistent with ordinary forgetting.
• C. The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
• D. The disturbance is not a normal part of a broadly accepted cultural or religious practice. Note: In children, the symptoms are not attributable to imaginary playmates or other fantasy play.
• E. The symptoms are not attributable to the physiological effects of a substance (e.g., blackouts or chaotic behavior during alcohol intoxication) or another medical condition (e.g., complex partial seizures).

Unique Aspects

• Alters – different identities or personalities
• Host – the identity that keeps other identities together
• Switch – quick transition from one personality to another

Controversy

• Some patients presenting with DID symptoms are faking (possibly subconsciously)
  • Example: Patients more likely to “produce” a fake alter when therapist suggests this possibility
• Some DID patients are not faking
  • Case studies reveal changes in physiological and brain function when switching between alters

Statistics

• Prevalence: not well known, perhaps 1 to 2%
• More common in females
• Onset is almost always in childhood or adolescence
• High comorbidity rates with other psychological disorders
• Typically follows lifelong, chronic course

Causes

• Typically linked to a history of severe, chronic trauma, often abuse in childhood
  • Risk increases if there is no social support after the trauma
• Mechanism: Dissociation offers an opportunity to escape from the impact of trauma
• Closely related to PTSD, possibly an extreme subtype
• Biological vulnerability possible but not well understood; almost all risk is environmental

Treatment

• Focus is on reintegration of identities
• Identify and neutralize cues/triggers that provoke memories of trauma/dissociation
• Patient may have to relive and confront the early trauma
  • Some achieve through hypnosis