AMNESIA

loss of memory as a result of brain injury or deterioration, shock, fatigue, senility, drug use, alcoholism, anesthesia, illness, or psychoneurotic reaction. Amnesia may be anterograde, in which events following causative trauma or disease are forgotten; or retrograde, in which events preceding the causative event are forgotten. The condition can often be traced to some severe emotional shock, in which case personal memories (e.g., identity), rather than less personal material (e.g., language skills), are affected. Such amnesia seems to represent a psychoneurotic escape from or denial of memories that might cause anxiety and is thus an example of repression, or motivated forgetting. These memories are not actually lost, since they can generally be recovered through psychotherapy or after the amnesic state has ended. Occasionally amnesia may last for weeks, months, or even years, during which time the person may begin an entirely new life pattern. Such protracted reactions are called fugue states. When recovered, the person is usually able to remember events that occurred prior to onset, but events of the fugue period are forgotten. Posthypnotic amnesia, the forgetting of most or all events that occur while under hypnosis in response to a suggestion by the hypnotist, has long been regarded as a sign of deep hypnosis. The common difficulty of remembering childhood experiences is sometimes referred to as childhood amnesia.