Dissociative Identity Disorder
The essential feature of dissociative identity disorder (DID) is the presence of two or more distinct personality states that recurrently take control of behavior.
In DID, each alternate personality (known as alter) has its own pattern of perceiving, relating to others, and thinking about the self and the environmentOpens in new window.
It is believed that severe sexual, physical, or psychological trauma in childhood predisposes an individual to the development of dissociative identity disorder.
Dissociative identity disorder appears to be associated with at least two dissociative identity states:
- one is a state or personality that functions on a daily basis and blocks access and responses to traumatic memories, and
- another state (also referred to as an alter state) is fixated on traumatic memories.
There is evidence of different regional cerebral blood flow patterns and autonomic and subjective reactions during each of these physiological states when the individual is exposed to trauma-related stimuli (Reinders et al., 2006).
Each alter is a complex unit with its own memories, behavioral patterns, and social relationships that dictate how the person acts when that personality is dominant.
Often the original or primary personality is religious and moralistic, and the alters are pleasure-seeking and nonconforming.
The alter personalities may behave as individuals of a different sex, race, or religion. The dominant hand and the voice may also be different; intelligence and electroencephalographic findings may also be altered.
Typical cognitive distortions include the insistence that alternate personalities inhabit separate bodies and are unaffected by the actions of one another. The primary personality or host is usually not aware of the alters and is perplexed by lost time and unexplained events.
Experiences such as finding unfamiliar clothing in the closet, being called a different name by a stranger, or not having childhood memories are characteristic of dissociative identity disorder.
Alters may be aware of the existence of each other to some degree. Transition from one personality to another (switching) occurs during times of stress and may range from a dramatic to a barely noticeable event. Some patients experience the transition when awakening. Shifts may last from minutes to months, although shorter periods are more common.
Several movies and TV shows that demonstrate actual case studies of individuals diagnosed with dissociative identity disorder have been produced, including Sybil (1976), The Three Faces of Eve (1957), Fight Club (1999), Me, Myself and Irene (2000), and the television series The United States of Tara.

Treatment Interventions
Advanced practice nurses and other skilled licensed mental health professionals use cognitive-behavioral therapyOpens in new window, psychodynamic psychotherapy, exposure therapy, modified EMDROpens in new window, hypnotherapyOpens in new window, neurofeedback, ego state therapies, somatic therapies, and medication to treat patients with dissociative disorders. Advanced traning is needed to treat these patients effectively as such, and ongoing supervision for the therapist is suggested.
Somatic Thrapy
DissociationOpens in new window causes people to experience a distressing fragmentation of consciousness and a sense of separation from themselves.
Disturbances of perception, sensation, autonomic regulation, and movement are common for those who have suffered significant trauma since trauma is often stored physically in the body.
Verbal and bodily psychotherapies are seen as complementary by the discipline of Dance Movement Therapists in working with traumatized dissociative patients in emotional recovery (Koch & Harvey, 2012).
A specific type of somatic psychotherapy, sensorimotor psychotherapyOpens in new window, combines talking therapy with body-centered interventions and movement to address the dissociative symptoms inherent in trauma (Ogden et al., 2006).
This type of therapy is integrated into phase-oriented trauma treatment to facilitate symptom reduction and stability, to integrate the traumatic memory, and to restore the person’s ability to stay in the present moment.
This therapy is based on the premise that the body, mind, emotions, and spirit are interrelated, and a change at one level results in changes in the others. Awareness, focusing on the present, and recognizing touch as a means of communicating are some of the principles of this therapy.
During psychotherapy sessions, the patient is asked to describe physical sensations he or she is experiencing. The goal is to safely disarm the pathological defense mechanism of dissociation and replace it with other resources, especially body awareness and mindfulness.