- 1 DSM-III
- 2 DSM-IV
- 3 DSM-5
In DSM-III, this category is a disorder called Amnestic Syndrome
A. Both short-term memory impairment (inability to learn new information) and long-term memory impairment (inability to remember information that was known in the past) are the predominant clinical features.
C. Evidence, from the history, physical examination, or laboratory tests, of a specific organic factor that is judged to be etiologically related to the disturbance.
Delirium and Dementia also involve memory impairment. In Delirium, however, there is also a clouding of consciousness; and in Dementia, there are other major intellectual deficits as well.
In Factitious Disorder with Psychological Symptoms, memory testing often yields inconsistent results. Furthermore, there is no organic etiological factor.
- Amnestic Disorder Due to a General Medical Condition
- Substance-Induced Persisting Amnestic Disorder
- Amnestic Disorder NOS
Memory impairment is also a feature of delirium and dementia. In delirium, memory dysfunction occurs in association with impaired consciousness, with reduced ability to focus, sustain, or shift attention. In dementia, memory impairment must be accompanied by multiple cognitive deficits (i.e., aphasia, apraxia, agnosia, or a disturbance in executive functioning) that lead to clinically significant impairment.
An amnestic disorder must be distinguished from Dissociative Amnesia and amnesia occurring in the context of other Dissociative Disorders (e.g., Dissociative Identity Disorder). By definition, an amnestic disorder is due to the direct physiological effects of a general medical condition or substance use. Furthermore, amnesia in Dissociative Disorders typically does not involve deficits in learning and recalling new information; rather, individuals present with a circumscribed inability to recall previous memories, usually of a traumatic or stressful nature.
For memory disturbances (e.g., blackouts) that occur only during intoxication with or withdrawal from a drug of abuse, the appropriate Substance Intoxication or Substance Withdrawal should be diagnosed and a separate amnestic disorder is not made. For memory disturbances that are associated with the use of medication, Adverse Effects of medication Not Otherwise Specified may be noted.
Other Amnestic Disorders
The presumed etiology of the amnestic disorder determines the diagnosis. If it is judged that the memory disturbance is a consequence of the direct physiological effects of a general medical condition (including head trauma), then Amnestic Disorder Due to a General Medical Condition is diagnosed. If the memory disturbance results from the persisting effects of a substance (i.e., a drug of abuse, a medication, or toxin exposure), then Substance-Induced Persisting Amnestic Disorder is diagnosed. When both a substance (e.g., alcohol) and a general medical condition (e.g., head trauma) have had an etiological role in the development of the memory disturbance, both diagnoses are given. If it is not possible to establish a specific etiology (i.e., dissociative, substance induced, or due to a general medical condition), Amnestic Disorder Not Otherwise Specified is diagnosed.
Malingering and Factitious Disorder
Amnestic disorder must be distinguished from Malingering and from Factitious Disorder. This difficult distinction can be assisted by systematic memory testing (which often yields inconsistent results in Factitious Disorder or Malingering) and by the absence of a general medical condition or substance use that is etiologically related to the memory impairment.
Age-Related Cognitive Decline
Amnestic disorder should be distinguished from the less efficient memory characteristic of Age-Related Cognitive Decline, which is within the expected age-adjusted normative range for the individual.