Symptom validity testing of feigned amnesia for a mock crime.

Perpetrators sometimes claim loss of memory for the crimes they have committed. For the neuropsychologist, the veracity of such crime-related amnesia is difficult to assess. The aim of the present study was to investigate whether Symptom Validity Testing (SVT) can be used to detect feigning of crime-related amnesia. Undergraduate students (N = 39) were instructed to commit a mock crime and asked to feign complete amnesia for the event. Subsequently, they were given 25 forced-choice items about the "crime" that were always followed by the correct answer and an equally plausible alternative. To counteract chance performance, test items were intermixed with 25 bogus questions that contained two equally plausible alternatives. Results show that a majority of participants (59%) scored below chance level on the critical items of the SVT. In addition, debriefing interviews showed that understanding the rationale behind the SVT was not related to chance performance. SVT procedures therefore might be helpful in identifying feigned crime-related amnesia.