Abstract:
Objective: Baseline cognitive testing is commonly considered in return-to-play decisions following sports-related concussion. However, some have noted that an athlete’s approach to testing can dramatically differ between baseline and post-concussion assessments. Studies from our lab (Bailey et al., 2006; Rabinowitz et al., submitted) and others’ (Duckworth et al., 2012) have demonstrated the influence of motivation on test performance. Although there are many measures of malingering, there is no measure with demonstrated sensitivity to a sincere, but unmotivated, approach to testing. Method: This study examines observational and performance-based measures of effort towards testing in 174 collegiate athletes participating in a concussion management program. Athletes were administered a battery of neuropsychological tests including ImPACT and the Vigil Continuous Performance Task at baseline. After testing, examiners completed a checklist of 26 motivation-related behaviors (MBCL). Vigil response Time Variability (RTV) was evaluated as a performance-based indicator of effort towards testing. Results: Principal components analysis of the MBCL revealed 3 components accounting for 39% of the variance in responses (Impulsivity, Engagement, and Boredom). Each subscale exhibited good internal consistency (alpha>.70). Boredom was not correlated with any ImPACT Composite scores. Impulsivity was negatively correlated with ImPACT Verbal Memory, Visual Memory, and Visual Motor Speed (R=-.35, -.25, -.33 respectively, all p<0.005). Engagement was positively correlated with Verbal and Visual Memory (R=.27 and .25 respectively, all p<0.005). Vigil RTV was negatively correlated with Verbal Memory (R=-.16, p<0.05) and Visual Motor Speed (R=-.36, p<0.001). Conclusion: These results further support the notion that poor motivation can cause underperformance on baseline cognitive testing. Guidelines for translating the MBCL and RTV into clinical practice will be discussed.