ERP correlates of malingered executive dysfunction

• We assessed the efficacy of an ERP measure of malingered executive dysfunction.
• There was no difference in the P3a response in malingerers compared to controls.
• Attempts to subvert the task result in other physiological indicators of deception.
• ERP paradigms may be useful in identifying those malingering executive deficits.

Assessment of malingering has become an integral part of many neuropsychological evaluations, particularly in forensic settings. However, traditional malingering measures are known to be vulnerable to both manipulation and coaching. Consequently, recent research has attempted to identify physiological indices of cognitive functioning that are less susceptible to overt manipulation. While prior studies have explored the validity of physiological assessment of memory deficits, this study evaluates the effectiveness of a physiological measure of executive functioning. This study used EEG recording in conjunction with a three-stimulus oddball design to compare neural responses in simulated malingerers feigning cognitive deficits associated with traumatic brain injury (TBI) and controls. Specifically, the study explored the efficacy of an event-related potential (ERP) known as P3a, which is believed to be an index of frontal lobe executive processes, specifically the attentional orienting response. The results of this study demonstrated that simulated malingerers did not produce a P3a response that was significantly different from control participants. Furthermore, the P3a in simulated malingerers did not demonstrate any of the properties reported in prior studies with TBI patients. Not only were malingerers unable to produce a significant change in their basic orienting response, but the very process of attempting to employ additional strategies to appear impaired produced other physiological markers of deception. Therefore, the P3a component appeared to be unaffected by an individual's motivation or overt performance, which suggests that it may have potential for development as a physiological measure for differentiating between malingerers and those with genuine TBI.