Memory performance after head injury: contributions of malingering, litigation status, psychological factors, and medication use.

Impaired memory test performance can reflect a host of factors, such as head injury/postconcussive syndrome, involvement in litigation, malingering behavior, psychological distress, and medication use. Such factors are important in interpreting memory test performances in patients referred in the context of litigation. We examined memory test performance in mild head-injured patients in litigation, mild to moderate head-injured patients not in litigation, severely head-injured patients not in litigation, depressed patients, and patients with somatization disorders. Findings showed that several memory tests were useful in distinguishing probable malingerers from the other groups. There was a complex interaction among malingering status, psychological status, and medication use in the prediction of memory test results. Although nonneurological factors were related to memory impairment, litigation status alone was not predictive of memory performance. The results emphasize the need to consider nonneurological factors in the interpretation of poor memory performance in patients seen for forensic evaluation.