The present study employed a computerized forced-choice recognition memory task, the Multi-Digit Memory Test (MDMT), to examine the effects of instructional set (i.e., dissimulation information provided subjects) and motivation (i.e., monetary incentive) on simulated malingering behavior in a group of 119 university undergraduate students and 33 patients sustaining varying severity of closed-head injury. For the nonpatient groups, a significant effect of instructional set was revealed. Motivational incentive, however did not affect forced-choice performance. Overall, significant performance differences emerged between all groups with nonmalingering students performing nearly perfectly, the brain-injured patients performing well above chance levels, sophisticated student malingers performing at chance, and naive student malingers performing well below chance levels. These results suggest the MDMT may offer a clinically useful and convenient addition to a neuropsychological assessment when there is suspicion of feigned memory problems. These data also support the use of naive and sophisticated malingering subjects in further analog studies addressing this topic.