22 - Malingering and feigned memory disorders

Summary

That various brain injuries affect memory in predictable ways provides clinical neuropsychologists with a means by which to determine if a feigned memory disorder appears probable. The question has become progressively more important as neuropsychologists are increasingly asked to evaluate patients in civil litigation (Matarazzo, 1990).

It is important to distinguish between two types of claimed memory impairment. One is the claim of amnesia for a significant event related to a crime. This is relatively common, with Parwatiker et al. (1985) reporting 70% of accused murderers claiming such amnesia. Even in homicide cases following conviction, Kopelman's (1987) review still found an incidence rate between 25 and 45%. This chapter does not address this type of feigned memory deficit. The reader is referred to Schacter (1986) for his thorough review of simulated amnesia. The second type of claim is a reduced ability to remember new information after a known or suspected acquired brain injury. This chapter reviews studies related to the methodology and techniques available for answering this question.

Some clinicians may argue that the only tools necessary to uncover malingerers are proper training and sufficient experience. However, studies have shown that neuropsychologists essentially perform at chance levels when asked to classify malingered versus actual brain injury protocols in adults (Heaton et al., 1978), adolescents (Faust et al., 1988b), and children (Faust et al., 1988a) using only neuropsychological measures. These studies (particularly those by Faust and colleagues) have been criticized on methodological grounds (Schmidt, 1989; Bigler, 1990), but they do suggest that having confidence in one's opinion does not necessarily correspond with the accuracy of one's conclusions.