For more information, see Amnestic Disorders and Mental Disorders Due to a General Medical Condition
A. The development of memory impairment as manifested by impairment in the ability to learn new information or the inability to recall previously learned information.
B. The memory disturbance causes significant impairment in social or occupational functioning and represents a significant decline from a previous level of functioning.
D. There is evidence from the history, physical examination, or laboratory findings that the disturbance is the direct physiological consequence of a general medical condition (including physical trauma).
- Transient: if memory impairment lasts for 1 month or less
- Chronic: if memory impairment lasts for more than 1 month
Note: Include the name of the general medical condition, e.g., Amnestic Disorder Due to Head Trauma; also record the general medical condition.
The following specifiers may be noted to indicate the duration of the disturbance.
This specifier is used to indicate durations usually from several hours to a few days and for no more than 1 month. When the diagnosis is made within the first month without waiting for recovery, the term "provisional" may be added. "Transient global amnesia" is a specific form of transient amnestic disorder, characterized by a dense, transitory inability to learn new information and a variable impaired ability to recall events that occurred just before, or in the midst of, the etiological cerebrovascular problem.
This specifier is used for disturbances that last for more than 1 month.
In recording the diagnosis of Amnestic Disorder Due to a General Medical Condition, the clinician should note the identified general medical condition judged to be causing the disturbance (e.g., Amnestic Disorder Due to Stroke). The general medical condition should also be noted (e.g., stroke).
Associated General Medical Conditions
An amnestic disorder often occurs as the result of pathological problems (e.g., closed head trauma, penetrating missile wounds, surgical intervention, hypoxia, infarction of the distribution of the posterior cerebral artery, and herpes simplex encephalitis) that cause damage to specific diencephalic and mediotemporal lobe structures (e.g., mammillary bodies, hippocampus, fornix). Pathology is most often bilateral, but deficits may arise from unilateral lesions. Transient Amnestic Disorder, when encountered as "transient global amnesia," is typically associated with cerebrovascular disease and pathology in the vertebrobasilar system. Transient Amnestic Disorder may also arise from episodic general medical conditions (e.g., metabolic conditions or seizures).