The Utility of the Test of Memory Malingering Trial 1 in Differentiating Neurocognitive, Emotional, and Behavioral Functioning in a Pediatric Concussion Population

Cognition and post-concussive symptom status after pediatric mild traumatic brain injury

Cognitive impairment and post-concussive symptoms (PCS) represent hallmark sequelae of pediatric mild traumatic brain injury (pmTBI). Few studies have directly compared cognition as a function of PCS status longitudinally. Cognitive outcomes were therefore compared for asymptomatic pmTBI, symptomatic pmTBI, and healthy controls (HC) during sub-acute (SA; 1-11 days) and early chronic (EC; approximately 4 months) post-injury phases. We predicted worse cognitive performance for both pmTBI groups relative to HC at the SA visit. At the EC visit, we predicted continued impairment from the symptomatic group, but no difference between asymptomatic pmTBI and HCs. A battery of clinical (semi-structured interviews and self-report questionnaires) and neuropsychological measures were administered to 203 pmTBI and 139 HC participants, with greater than 80% retention at the EC visit. A standardized change method classified pmTBI into binary categories of asymptomatic or symptomatic based on PCS scores. Symptomatic pmTBI performed significantly worse than HCs on processing speed, attention, and verbal memory at SA visit, whereas lower performance was only present for verbal memory for asymptomatic pmTBI. Lower performance in verbal memory persisted for both pmTBI groups at the EC visit. Surprisingly, a minority (16%) of pmTBI switched from asymptomatic to symptomatic status at the EC visit. Current findings suggest that PCS and cognition are more closely coupled during the first week of injury but become decoupled several months post-injury. Evidence of lower performance in verbal memory for both asymptomatic and symptomatic pmTBI suggests that cognitive recovery may be a process separate from the resolution of subjective symptomology.

Self-reported disability-seeking predicts PVT failure in veterans undergoing clinical neuropsychological evaluation

Objective: This study examined disability-related factors as predictors of PVT performance in Veterans who underwent neuropsychological evaluation for clinical purposes, not for determination of disability benefits. Method: Participants were 1,438 Veterans who were seen for clinical evaluation in a VA Medical Center's Neuropsychology Clinic. All were administered the TOMM, MSVT, or both. Predictors of PVT performance included (1) whether Veterans were receiving VA disability benefits ("service connection") for psychiatric or neurological conditions at the time of evaluation, and (2) whether Veterans reported on clinical interview that they were in the process of applying for disability benefits. Data were analyzed using binary logistic regression, with PVT performance as the dependent variable in separate analyses for the TOMM and MSVT. Results: Veterans who were already receiving VA disability benefits for psychiatric or neurological conditions were significantly more likely to fail both the TOMM and the MSVT, compared to Veterans who were not receiving benefits for such conditions. Independently of receiving such benefits, Veterans who reported that they were applying for disability benefits were significantly more likely to fail the TOMM and MSVT than were Veterans who denied applying for benefits at the time of evaluation. Conclusions: These findings demonstrate that simply being in the process of applying for disability benefits increases the likelihood of noncredible performance. The presence of external incentives can predict the validity of neuropsychological performance even in clinical, non-forensic settings.

The minimal effect of depression on cognitive functioning when accounting for TOMM performance in a sample of U.S. veterans

While many studies have demonstrated a relationship between depression and cognitive deficits, most have neglected to include measurements of performance validity. This study examined the relationship between depression and cognition after accounting for noncredible performance. Participants were veterans referred for outpatient clinical evaluation. The first set of regression analyses (N = 187) included age, sex, and education in Model 1, Beck Depression Inventory-2 (BDI-2) added in Model 2, and pass/failure of Test of Memory Malingering (TOMM) added in Model 3 as predictors of 12 neuropsychological test indices. The second set of analyses (N = 559) mirrored the first but with Major Depressive Disorder (MDD) diagnosis in Models 2 and 3. In the first analyses, after including TOMM in the model, only the relationship between BDI-2 and verbal fluency remained significant, but this did not survive a Bonferroni correction. In the second analyses, after including TOMM and Bonferroni correction, MDD diagnosis was a significant predictor only for CVLT-II Short Delay Free Recall. Therefore, the relationship between depression and cognition may not be driven by frank cognitive impairment, but rather by psychological mechanisms, which has implications for addressing depressed individuals' concerns about their cognitive functioning and suggest the value of providing psychoeducation and reassurance.