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Overview of Dissociative Disorders


David Spiegel

, MD, Stanford University School of Medicine

Last full review/revision Mar 2021| Content last modified Mar 2021
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Occasionally everyone has minor problems integrating their memories, perceptions, identity, and consciousness. For example, people may drive somewhere and then realize that they do not remember the drive. They may not remember it because they are absorbed—with personal concerns, a program on the radio, or a conversation with a passenger—or are just daydreaming. Such problems, referred to as normal dissociation, typically do not disrupt everyday activities.

In contrast, people with a dissociative disorder may totally forget activities that occurred over minutes, hours, or sometimes much longer. They may sense they are missing a period of time. In addition, they may feel detached (dissociated) from themselves—that is, from their memories, perceptions, identity, thoughts, emotions, body, and behavior. Or they may feel detached from the world around them. Thus, their sense of identity, memory, and/or consciousness is fragmented.

Dissociative disorders involve the following:

Did You Know...

  • A minor blow to the head cannot cause people to suddenly forget who they are and everything they know.

Dissociative disorders are usually triggered by overwhelming stress or trauma. For example, people may have been abused or mistreated during childhood. They may have experienced or witnessed traumatic events, such as accidents or disasters. Or they may experience inner conflict so intolerable that their mind is forced to separate incompatible or unacceptable information and feelings from conscious thought.

Recent research in animals and humans has begun to show that certain underlying brain structures and functions appear to be associated with dissociative disorders. Scientists do not yet understand how these abnormalities cause dissociative disorders or how this knowledge could guide treatment, but they appear to be promising leads that would benefit from further research.

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