This study aimed to investigate the dual-task cost of both motor and cognitive performances in patients with multiple sclerosis (PwMS) and in healthy controls and to determine their relationships with clinical features in PwMS. The participants performed motor tasks (postural stability, walking, and manual dexterity) and cognitive tasks (mental tracking and verbal fluency) under single- and dual-task conditions. The results showed that postural stability under dual-task conditions did not change, whereas walking and manual dexterity deteriorated, regardless of the concurrent cognitive task, in PwMS (median Expanded Disability Status Scale score: 1) and the healthy controls. Verbal fluency decreased during postural stability, whereas it increased during walking, and it was maintained during manual dexterity in both groups. Mental tracking did not change during walking; it declined during manual dexterity in both groups. Mental tracking during postural stability deteriorated in PwMS, while it did not change in the healthy controls. In general, dual-task costs were associated with baseline performances of tasks rather than clinical features. Therefore, baseline performances of both tasks should be increased for improving dual-task performance in PwMS.

这项研究旨在调查多发性硬化症（PwMS）患者和健康对照者的运动和认知表现的双重任务成本，并确定他们与PwMS中临床特征的关系。参与者在单任务和双任务条件下执行了运动任务（姿势稳定性，步行和手部敏捷）和认知任务（心理跟踪和言语流畅）。结果表明，在同时进行认知任务的情况下，在双任务情况下的姿势稳定性没有改变，而在同时进行的认知任务下，PwMS（中度扩展残疾状态量表评分：1）和健康对照者的行走和手部敏捷性恶化。在姿势稳定过程中，两组的口语流利性下降，而在步行过程中，其流利度增加，并且在手部敏捷度过程中，口语流利性得以保持。步行过程中的心理跟踪没有改变。在两组中，它在手巧期间都下降了。在PwMS中，姿势稳定过程中的心理跟踪恶化，而在健康对照组中则没有变化。通常，双重任务成本与任务的基线性能而不是临床特征相关。因此，应提高两个任务的基准性能，以改善PwMS中的双任务性能。