Examining the Discrepancy between Subjective Cognitive Complaints and Processing Speed Performance in Military...

To examine correlates of the discrepancy between subjective cognitive complaints and processing speed performance in a sample of military personnel with and without traumatic brain injury (TBI).

About 235 U.S. military service members (31 noninjured controls [NIC], 69 injured controls [IC], 70 uncomplicated mild TBI [mTBI], and 65 complicated mild/moderate/severe TBI [sTBI]) prospectively enrolled in a longitudinal TBI study completed neuropsychological testing, performance validity tests, and self-report measures of cognitive complaints and psychological symptoms. Service members were categorized as "Accurate Estimators," "Underestimators," and "Overestimators" based on discrepancies between their subjective cognition and processing speed performance.

The NIC group was less likely to underestimate their cognitive abilities than the mTBI group (p < .05). Discrepancy groups significantly differed in processing speed scores (p < .001), with underestimators demonstrating the best objective cognitive performance. Spearman correlations revealed significant positive correlations between unadjusted discrepancy scores and psychological symptoms in the NIC, IC, and sTBI groups (ps < 0.05) but not the mTBI group (ps > 0.05). In contrast, discrepancy scores adjusted for premorbid intelligence were consistently and positively correlated with psychological symptoms across all injury groups (ps < 0.05).

Findings suggest that mTBI injuries may increase the likelihood of a patient underestimating their cognitive performance. Further, premorbid cognitive functioning is an important factor in evaluating discrepancies in self-reported cognitive complaints and processing speed performance.