dissociative amnesia: when a person is unable to recall important personal information, usually after
some stressful episode. The information is not permanently lost, but it cannot be retrieved during the
episode of amnesia.
rarely, the amnesia is for only selected events during a circumscribed period of distress, is continuous
from a traumatic event to the present, or is total, covering the person’s entire life.
The person’s behaviour during the period of amnesia is otherwise unremarkable, except that the
memory loss may bring some disorientation and purposeless wandering.
The amnesic episode may last several hours or as long as several years. It usually disappears as
suddenly as it came on, with complex recovery and only a small change of recurrence.
In degenerative brain diseases, memory fails more slowly over time, is not linked to life stress, and is
accompanied by other cognitive deficits, such as the inability to learn new information. Memory loss
following a brain injury caused by some trauma (eg an automobile accident) or substance abuse can be
easily linked to the trauma or the substance being abused.
Memory loss is more extensive in dissociative fugue than in dissociative amnesia. The person not only
becomes totall amnesic but suddenly leaves home and work and assumes a new identity. Sometimes
the person takes a new name, a new home, a new job, and even a new set of personality characteristics.
More often, the fugue is of briefer duration. It consists for the most part of limited, but apparently
purposeful, travel, during which social contacts are minimal or absent.
Fugues typically occur after a person has experienced some sever stress, such as marital quarrels,
personal rejection, financial or occupational difficulties, war service, or a natural disaster. Recovery,
although it takes varying amounts of time is usually complete and the individual does not recollect what
took place during the flight from his or her usual haunts.
depersonalization disorder: unlike other dissociative disorde