DEFINITION

• Dissociative amnesia is classified under the Dissociative Disorders section of the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5)[1].
  • Previously known as psychogenic amnesia, renamed dissociative amnesia in DSM-IV[2]
  • Characterized by an apparent disruption of and/or discontinuity in the normal integration of consciousness, memory, identity, emotion, perception, body representation, motor control, and behavior
  • The DSM-5 lists the defining feature as inability to recall important autobiograpical information, usually of a traumatic or stressful nature, that is inconsistent with ordinary forgetting.
• This is a controversial diagnostic entity that incorporates elements of psychogenic fugue states (psychogenic amnesia), repressed memory, traumatic amnesia, and conversion.
  • The concept of repression (repression of memory regarding traumatic events) remains controversial, with scientific studies often being interpreted as supportive of both sides of the argument.
• May overlap with dissociative fugue, which is apparently purposeful travel or bewildered wandering that is associated with autobiographical amnesia[1]

• The DSM-5 lists a variety of memory disturbances that can occur in dissociative amnesia[1]:
  • Localized amnesia (the most common form): failure to recall events during a circumscribed period of time
  • Selective amnesia: can recall some, but not all parts of a circumscribed period of time or traumatic event
  • Systematized amnesia: loss of memory for a specific category of information
  • Continuous amnesia: loss of memory for each new event as it occurs
  • Generalized amnesia (rare): acute onset of complete loss of memory for one’s life history
    • May lose semantic knowledge, procedural knowledge, and/or personal identity
• Some authors feel this disorder is more common in combat veterans, sexual assault victims, and extreme emotional stress or conflict, while others see this as a disorder of vulnerable individuals with comorbid psychiatric conditions, problematic life circumstances, and/or personality vulnerabilities.
• Controversy exists whether dissociative amnesia should be conceptualized as a dissociative disorder or included in the symptom clusters for PTSD and acute stress disorder, emphasizing its relationship to trauma[3].