Assessing the enduring residual neuropsychological effects of head trauma in college athletes who participate in contact sports.

The present study examined the enduring residual neuropsychological effects of head trauma in college athletes using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Postconcussion Syndrome Checklist, and the Stroop task. Based on a brief self-report concussion history survey, male and female athletes who participated in ice hockey, field hockey, lacrosse, and/or soccer were assigned to one of three concussion-history conditions: Non-concussed, Non-recent concussed (i.e., more than 2 years since last concussion), or Recent concussed (i.e., 2 years or less since last concussion). A fourth group of subjects consisting of non-concussed/non-athletes served in the control condition. Group differences emerged on the RBANS when immediate memory, delayed memory, and total scores were analyzed. Specifically, recent concussed athletes and, surprisingly, non-concussed athletes scored lower than control subjects in the two memory domains, whereas all three athlete groups had lower total RBANS scores than those of control subjects. Moreover, recent concussed athletes not only had lower immediate memory scores than control subjects, but also were impaired relative to non-recent concussed athlete subjects in this memory domain. No group differences were detected on the Stroop task or on the Postconcussion Syndrome Checklist. Interestingly, however, the severity of the Postconcussion Syndrome Checklist scores for the two athlete-concussed groups, taken in aggregate, correlated negatively with RBANS scores for attention (r = -.65) and delayed memory (r = -.61), and with the total RBANS score (r = -.59). In recent concussed athletes, lower delayed memory scores correlated with more severe Postconcussion Symptom Checklist scores (r = -.90), while more severe/higher number of concussions correlated with increased processing speed on the Stroop interference task (r = .90). These findings indicate that recent head injury produces alterations in neuropsychological function, especially that of memory, that resolve with time. More provocatively, the data also suggest that participation in contact sports may produce sub-clinical cognitive impairments in the absence of a diagnosable concussion presumably resulting from the cumulative consequences produced by multiple mild head trauma.