Amnestic disorder refers to a form of cognitive disorder characterized by memory impairments that are more limited or circumscribed than those seen in dementia or delirium.
Other definition:
Amnestic Disorder refers to the deterioration in the ability to transfer information from short to long-term memory, in the absence of other Dementia symptoms, as a result of head trauma or drug abuse. Likewise, it is a cognitive disorder involving the inability to recall previously learned information or to register new memories.
The Amnestic Disorder are a group of disorders that involve loss of memories previously established, loss of the ability to create new memories, or loss of the ability to learn new information. As defined by the mental health professional's handbook, the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision (2000), also known as DSM-IV-TR, the amnestic disorders result from two basic causes: general medical conditions that produce memory disturbances; and exposure to a chemical (drug of abuse, medication, or environmental toxin). An amnestic disorder whose cause cannot be definitely established may be given the diagnosis of amnestic disorder not otherwise specified.