Detecting feigned traumatic brain injury with eye tracking during a test of performance validity
Year, Volume, Issue, Page(s):
, 34, 3, 308-320
Study examined the utility of eye-tracking on a clinical performance validity test (PVT) in distinguishing adults with verified traumatic brain injury (TBI) from adults coached to feign cognitive impairment. Research has established that ocular behaviors are reliable biomarkers of (un)conscious cognitive processes, and they have distinguished deceptive from honest responding in experimental paradigms. A PVT linked to eye-tracking was completed in the context of a full neuropsychological battery by 49 adults with moderate-to-severe TBI (TBI), 47 healthy adults coached to simulate TBI (SIM), and 67 healthy comparison adults providing full effort (HC). Kruskal-Wallis tests revealed that eye-tracking indices did not differ among the groups during presentation of stimulus items but did differ during forced-choice trials. Compared to TBI and HC, SIM had significantly more transitions, fixations, and time spent looking at correct and incorrect response options. Logistic regressions and receiver operating characteristics curve analyses showed that accuracy was the best predictor of SIM versus HC. For SIM versus TBI, eye-tracking indices exceeded accuracy in distinguishing the groups. Eye-tracking added incremental predictive value to accuracy for both SIM-HC and SIM-TBI discriminations. Eye-tracking indicated that individuals feigning TBI showed multiple signs of greater cognitive effort than those with verified TBI and healthy comparisons. In the comparison of greatest interest (SIM versus TBI), eye-tracking best predicted group status and yielded excellent discrimination when combined with accuracy. Eye-tracking may be an important complement to traditional accuracy scores on PVTs.
Kanser, Robert J.|Bashem, Jesse R.|Patrick, Sarah D.|Hanks, Robin A.|Rapport, Lisa J.|