What is dissociative amnesia?

Dissociative amnesia is a condition in which a person cannot remember important information about his or her life. This forgetting may be limited to certain specific areas (thematic), or may include much of the person’s life history and/or identity (general).

In some rare cases called dissociative fugue, the person may forget most or all of his personal information (name, personal history, friends), and may sometimes even travel to a different location and adopt a completely new identity. In all cases of dissociative amnesia, the person has a much greater memory loss than would be expected in the course of normal forgetting.

Dissociative amnesia is one of a group of conditions called “dissociative disorders.” Dissociative disorders are mental illnesses in which there is a breakdown of mental functions that normally operate smoothly, such as memory, consciousness or awareness, and identity and/or perception.

Dissociative symptoms can be mild, but they can also be so severe that they keep the person from being able to function, and can also affect relationships and work activities.

How common is dissociative amnesia?

Dissociative amnesia is rare; it affects about 1% of men and 2.6% of women in the general population. The environment also plays a role; rates of dissociative amnesia tend to increase after natural disasters and during war.

What causes dissociative amnesia?

Dissociative amnesia has been linked to overwhelming stress, which may be caused by traumatic events such as war, abuse, accidents, or disasters. The person may have suffered the trauma or just witnessed it. There also seems to be a genetic (inherited) connection in dissociative amnesia, as close relatives often have the tendency to develop amnesia.

What are the symptoms of dissociative amnesia?

There are three types, or patterns, of dissociative amnesia:

  • Localized: Memory loss affects specific areas of knowledge or parts of a person’s life, such as a certain period during childhood, or anything about a friend or coworker. Often the memory loss focuses on a specific trauma. For example, a crime victim may have no memory of being robbed at gunpoint, but can recall details from the rest of that day.
  • Generalized: Memory loss affects major parts of a person’s life and/or identity, such as a young woman being unable to recognize her name, job, family, and friends.
  • Fugue: With dissociative fugue, the person has generalized amnesia and adopts a new identity. For example, one middle manager was passed over for promotion. He did not come home from work and was reported as missing by his family. He was found a week later, 600 miles away, living under a different name, working as a short-order cook. When found by the police, he could not recognize any family member, friend, or coworker, and he could not say who he was or explain his lack of identification.

Dissociative amnesia is different from amnesia caused by medical problems, such as illnesses, strokes, or brain injuries. In medically caused amnesia, recovering memories is rare and generally a slow and gradual process.

Most cases of dissociative amnesia are relatively short. Often, when memories return, they do so suddenly and completely. Memory recovery may happen on its own, after being triggered by something in the person’s surroundings, or in therapy.

Another difference is that people who suffer medical amnesia are quite upset by their memory loss, whereas most people with dissociative amnesia seem to have surprisingly little concern over their amnesia.

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