A Comparison of Implicit and Explicit Motor Sequence Learning in Patients with Relapsing-Remitting Multiple Sclerosis

Motor sequence learning in a goal-directed stepping task in persons with multiple sclerosis: a pilot study

Motor sequence learning in persons with multiple sclerosis (pwMS) and healthy controls (HC) under implicit or explicit learning conditions has not yet been investigated in a stepping task. Given the prevalent cognitive and mobility impairments in pwMS, this is important in order to understand motor learning processes and optimize rehabilitation strategies. Nineteen pwMS (the Expanded Disability Status Scale = 3.4 ± 1.2) and 18 HC performed a modified serial reaction time task by stepping as fast as possible on a stepping tile when it lit up, either with (explicit) or without (implicit) knowledge of the presence of a sequence beforehand. Motor sequence learning was studied by examining response time changes and differences between sequence and random blocks during the learning session (acquisition), 24 h later (retention), and in three dual-task (DT) conditions at baseline and retention (automaticity) using subtracting sevens, verbal fluency, and vigilance as concurrent cognitive DTs. Response times improved and were lower for the sequenced compared with the random blocks at the post- and retention tests (P's < 0.001). Response times during DT conditions improved after learning, but DT cost improved only for the subtracting sevens DT condition. No differences in learning were observed between learning conditions or groups. This study showed motor sequence learning, by acquisition and retention, in a stepping task in pwMS with motor impairments, to a similar degree as HC and regardless of learning conditions. Whether automaticity increased remains unclear.

Motor reaction time and accuracy in patients with multiple sclerosis: effects of an active computerized training program

In this study, we aimed to determine the difference of motor reaction time and accuracy between the patients with moderate multiple sclerosis (MS) and healthy subjects and to determine whether a specified cognitive-motor training can improve the speed and accuracy of information processing in patients with MS. A total of 205 patients (30% males) and 276 age-/gender-matched healthy subjects (31% males) were included in the study. Furthermore, using a stratified randomization method, patients with MS were randomly assigned to one of two groups: active information processing training (AIPT) (n = 49) or post-control (n = 55). The AIPT group was asked to complete a computerized visual-manual training program and the post-control group asked to complete the same task without an increase in difficulty. Before and after the intervention phase, the simple, choice, and semantic reaction times and accuracies of all participants were evaluated using the VLS measurement battery. Our results demonstrated that the case and control group were significantly different in terms of the simple, choice, and semantic motor reaction times and accuracies. Compared with the pre-intervention phase, the AIPT and control group's performances in the post-intervention phase were considerably improved in simple, choice, and semantic motor reaction times and choice and semantic motor reaction accuracies. The results also showed that the AIPT group performed significantly better than the post-control group in terms of simple and choice motor reaction times. We showed the positive effects of training on the performance of patients with MS in motor reaction time and accuracy.