Abuse, not financial incentive, predicts non-credible cognitive performance in patients with psychogenic non-epileptic seizures.

Participants with psychogenic non-epileptic seizures (PNES) who fail symptom validity testing (SVT) perform worse on neuropsychological testing than those who do not, consistent with results found in participants with different clinical presentations (e.g., mild traumatic brain injury). However, little is known about how variables typically associated with SVT failure in other populations (e.g., the presence of financial incentives, exaggerated report of psychopathology) correlate with SVT failure in participants with PNES. Likewise the relationship between SVT failure and reported abuse, one of the most frequently described demographic characteristics of the PNES population, has not been examined. We found that failure on the Word Memory Test (WMT) in 91 participants with PNES was strongly associated with reported abuse but, contrary to expectations, was not associated with the presence of financial incentives or severity of reported psychopathology. These results indicate that the factors driving WMT failure may differ significantly in participants with PNES in ways that are potentially clinically relevant.