Abstract

Objective: This study compared driving using a virtual reality driving simulator (VRDS), cognitive functioning, and fatigue in Multiple Sclerosis (MS) individuals with age and education-matched healthy controls (HC). Method: 26 MS (mean age = 47.46), and 21 HC (Mean age = 42.09) were administered the Fatigue Severity Scale, Trails B, Paced Auditory Serial Addition Test-2 second condition, Timed Walking Test, and 9-hole Peg Test. All the participants drove a standardized route in the VRDS. Center lane (CL) and speed deviations were examined for a simple straight lane segment, with and without distractions. Results: Paired samples t-test revealed differences in driving performance only for the HC group. Specifically, HC's driving speed varied more during the undistracted (M = 2.50, SD = 1.46) vs. distracted (M = 1.75, SD = 0.99) driving segment, t(20) = −2.314, p = 0.03. However, driving speed was not associated with any cognitive or physical measures. MS participants' CL deviations were associated with fine motor movement during undistracted (r = 0.45, p = 0.05) and distracted driving (r = 0.49, p = 0.03). In contrast, HC's CL deviations were associated with working memory during undistracted (r = 0.50, p = 0.03) and distracted (r = 0.63, p = 0.004) driving. Fatigue severity (r = 0.56, p = 0.03) was associated with undistracted driving in the MS group. Conclusion(s): Driving performance of MS individuals was affected by physical symptoms and cognitive symptoms played a more important role for HC. In MS individuals, fatigue may be the moderating factor between driving and cognition.