The effects of closed head injury upon human memory: An experimental analysis

Patients with minor closed head injuries have been found to demonstrate a specific deficit in the recall of concrete material, which indicates an impairment in the use of mental imagery as a mnemonic code. The present study found a similar pattern of results when patients with either minor or severe closed head injuries were compared with other accident victims. Both the headinjured subjects and their matched controls demonstrated an additional impairment in immediate free recall, which was attributed to a reduced working-memory capacity. Any serious accident appears to impair human cognitive function in a generalised manner by acting as a source of situational stress. This has important implications for the choice of an appropriate control group in research into closed head injury. When compared with orthopaedic patients tested at similar intervals after their accidents, head-injured patients show a disturbance of memory function which is entirely attributable to a reduced capacity to employ mental imagery as an elaborative mnemonic code