Amnestic disorders

Abstract

Amnestic disorders may involve deficits in the encoding or storage of information in memory, or in retrieval of information from memory. Etiologies vary and include traumatic brain injury, neurodegenerative disease, and psychiatric illness. Different forms of amnesia can be distinguished: anterograde amnesia affects memory for the present, and retrograde amnesia affects memory for the past. Different memory systems may also be affected (working memory, episodic memory or semantic memory). This entry discusses hippocampal amnesia, amnesia caused by Alzheimer's disease (including mild cognitive impairment), memory dysfunction caused by vascular cognitive impairment, Korsakoff's syndrome, posttraumatic amnesia, transient global amnesia, transient epileptic amnesia, and psychogenic amnesia.