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Dissociative Disorders

NAMI, the National Alliance on Mental Illness, defines dissociative disorders as "an involuntary escape from reality characterized by disconnection between thoughts, identity, consciousness, and memory." DSM-5 specifies three varieties: dissociative identity disorder (DID), dissociative amnesia, and depersonalization/derealization disorder.

Not all dissociative states are abnormal. From a cognitive perspec­tive, a dissociative state is defined by three things: intelligent behavior, absence of normal awareness, and amnesia for the period of time during which the behavior is carried out.

This commonly occurs with motor activity that is highly practiced, as discussed in Chapter 7 under the heading of automaticity. An example of a normal dissociative state is carrying out a simple motor task absent-mindedly. The task can be anything from knitting to picking peas to driving.

When a stream of activity is indepen­dent of consciousness, it leaves no record in autobio­graphical memory. A person will have amnesia for the period of time involved.

What are criteria of a dissociative state "from a cognitive perspective"?

The most common dissociative state listed in DSM-5 is sleepwalking. Ironically, it is not even categorized as a dissociative state in DSM-5, apparently because it is not an escape from reality. It is listed under a separate section for Sleep Disorders. Sleepwalking is described there as a "non-rapid eye movement sleep arousal disorder."

Why can sleepwalking be defined as a dissociative state? Why is it not so classified, in DSM-5?

However, sleepwalking meets the three cognitive criteria of a dissociative state: (1) It is intelligent activity (sleepwalkers avoid obstacles, walk up and down stairs, open doors) (2) The person's normal awareness is absent or distracted (in fact, sleepwalkers are usually dreaming about something unrelated to the sleepwalk) (3) The individual has amnesia for the event later (sleepwalkers do not remember the events of the sleepwalk).

Much more rare than sleepwalking is the dissociative fugue state–an extended episode of automatic action or wandering followed by complete amnesia for the time of the activity. In DSM-5, fugue states are considered a form of dissociative amnesia. Fugue states are often associated with epilepsy and may be set off by seizure activity.

What are characteristics of a dissociative fugue state?

Rice and Fisher (1976) reported a case in which a young man had fugue states lasting from minutes to hours that occurred every day. He also had a history of seizures. They write:

The patient remembers walking down the stairway of his residence... and the next thing he knew he was on the eighth floor of a hospital about 5 miles from his home. He must have walked the entire dis­tance as he had no money with him.

By coincidence, an acquaint­ance saw him there and asked him whom he was visiting. The patient suddenly emerged from his fugue, felt very embar­rassed, made up some trivial excuse for being there, and walked back home. The father had been a patient in this hospital and on that floor at the time of his death.

The most spectacular form of disso­ciative state is Dissociative Identity Disorder or "multiple personality." It was described in Chapter 11 (Personality) along with a review of controversies over its causation.

A survey of 301 board-certified psychiatrists showed that only 21% believed there was strong evidence for DID. 43% described themselves as "skeptical" about it, especially the tie between diagnosis of DID and recovered memory therapies (Gharaibeh, 2009).

What percentage of psychiatrists were skeptical about DID, in one survey?

Sociocultural influences may be involved in DID, but that is almost irrelevant to the DSM-5. "Exper­iences of pathological possession"–spirit possession, in other words–are also included in DSM, in an effort to be "more applicable to culturally diverse situations."

DSM-5 specifies five criteria for a diagnosis of DID:

Chris Sizemore, the woman described in The Three Faces of Eve, was apparently a spontaneous case of DID. Unbe­knownst to the first personality, her second personality wrote a letter to her psychia­trist before Chris was ever placed under hypnosis or suspected of having multiple personalities.

However, the psychiatrists who worked with "Eve" (Thigpen and Cleckley) thought spontaneous cases of DID were extremely rare. They wrote that, out of hundreds of cases presented to them after they published their book, only one seemed to be authentic. By "authentic" they meant spontaneously occurring outside of therapy.

Dissociative amnesia is one of the three types of dissociative disorder in DSM-5. It is defined as loss of autobiographical memory associated with a traumatic event. To fit this diagnosis, the memory loss must not be attributable to biological causes or substance abuse or DID.

Dissociative amnesia is said often to be "co-morbid with" (found in the same person as) post-traumatic stress syn­drome (PTSD). The individual may also have partial flashbacks or nightmares.

Even if these syndromes may occasion­ally occur in the same individual, they are two different things. Dissocia­tive amnesia is forgetting a traumatic event. PTSD commonly features intrusive memories. Berntsen and Rubin (2013) say there is little evidence for dissoc­iative amnesia in PTSD but abundant evidence for intrusive memories in PTSD.

What is dissociative amnesia? What symptom is more likely to be associated with PTSD?

Dissociative amnesia may occur in connection with fugue states. Sharma, Guirguis, Nelson, and McMahon (2015) describe one such case:

Mr A, a 20-year-old man with no past medical and psychiatric history, was brought to the emergency department by his mother (Monday). He had difficulty remembering things for the past 2 days.

According to his mother, he was doing fine until 2 days ago (Satur­day). The next day (Sunday) when Mr A was at work, the mother got a call from Mr A's supervisor at his office stating that he did not recog­nize his friends and that he was asking what he was supposed to do at work. Considering the situation, Mr A's supervisor sent him home at 9:30 a.m. When he reached home, Mr A failed to recognize his mother, dog, siblings, and belongings.

He slept until 1 pm on Sunday, woke up, and left the house without telling anybody. Later in the evening, his mom got concerned and started calling and sending him text messages, which went unanswered. She called his friends, and they were able to locate him in the parking lot of a convenience store. Mr A did not recall how or why he came to the parking lot.

At admission to the inpatient psychiatry unit, Mr A's urine drug screen tested negative for any illicit substances. Findings of a head computed tomo­graphy scan and magnetic resonance imaging were within normal limits.... The immediate recall was intact, but he was unable to provide important details pertaining to his life.

...When asked about any recent stressor, the mother recalled that about a week ago Mr A had broken up with his partner. They were in a relationship for about 1 year, but his mom did not notice emotional changes in Mr A after the breakup. The family was not opposed to Mr A's sexual orientation.

...During his psychiatric inpatient stay, Mr A continued to have no autobiographic memory. The treatment team did not force Mr A to recall the stressor that might have led to the dissociative amnesia and fugue. The family was allowed to have conversation with Mr A and show him the family photo album, but at his ease.

Throughout the hospital course, Mr A was calm, and the memory loss did not seem to bother him. It was evi­dent that he was forming fresh mem­ories and could recall most events after he was found in the parking lot of the convenience store...

...After multiple sessions, Mr A started to recall memories about his past. He talked about how 'painful' his previous relationship was when he broke up with his partner... After a series of sessions over a period of 12-16 weeks, Mr A continued to show progress by returning to his job and started remembering details from his past.

...As depicted in this case, the most consistently successful treatment appears to be removal of the patient from threats; providing psychological support, gentle suggestion and cuing; and 'reteaching.' Empathy rather than skepticism is essential to create a safe and effective environ­ment for better therapeutic alliance.

Depersonalization Disorder

The last category of dissociative disorder included in DSM-5 is depersonalization disorder. This occurs when a person has feelings of being disconnected from reality, or that the world is not real. The surroundings and other people may appear as if in a dream.

What is depersonalization disorder? What is derealization?

Depersonalization may be coupled with "derealization" in the depersonality-derealization syndrome. Derealization is feeling detached from surroundings, feeling that life events are unreal, objects change in shape, size, or color, familiar people seem as if strangers, and familiar environments seem unfamiliar.

In other words, derealization involves the environment seeming unreal, while depersonalization involves the self feeling unreal. Patients can feel one or both, and symptoms can be chronic (long-lasting) or sporadic.

Psychotherapy is sometimes helpful with people suffering depersonal­ization disorder. Medications (anti-depressants and anticonvul­sants) sometimes work. No single treatment excels, but long-term prognosis for patients is good. In most cases, symptoms improve with time.


Berntsen, D. & Rubin, D. C. (2013) Involuntary memories and dissociative amnesia. Clinical Psychological Science, 2, 184-186. doi:10.1177/2167702613496241

Gharaibeh, N. (2009) Dissociative identity disorder: Time to remove it from DSM-5? Current Psychiatry, 8, 30-36.

Rice, E. & Fisher, C. (1976) Fugue states in sleep and wakefulness: a psychophysiological study. Journal of Nervous and Mental Diseases, 163, 79-87.

Sharma, P., Guirguis, M., Nelson, J., & McMahon, T. (2015) A case of dissociative amnesia with dissociative fugue and treatment with psychotherapy. Primary Care Companion for CNS Disorders, 17. Retrieved from: doi:10.4088/PCC.14l01763

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