Inter-relationships among retrograde amnesia, post-traumatic amnesia, and time since head injury: a retrospective study.

A questionnaire is described and data are analyzed from 1000 young adults who retrospectively reported on features of memory lapses associated with head injury with loss of consciousness as it may have occurred in their lifetimes. It was found that 24% of the males and 16% of the females claimed a former head injury with loss of consciousness. Lengths of retrograde amnesia, post-traumatic amnesia, and the length of time that had passed since the head injury are shown to be related to each other.