Amnesias, Retrograde

Loss of the ability to recall information that had been previously encoded in Memory prior to a specified or approximate point in Time. This process may be organic or psychogenic in origin. Organic Forms may be associated with Craniocerebral Trauma; Cerebrovascular Accidents; Seizures; Dementia; and a wide variety of other conditions that impair cerebral function. (From Adams et al., Principles of Neurology, 6th ed, pp426-9)