Short-Term Motor Learning and Retention during Visually Guided Walking in Persons with Multiple Sclerosis

Abstract

Background. The ability to adapt, a form of short-term motor learning, and retain this adaptation, is essential for rehabilitation and for day-to-day living. Yet little research is available on this topic in persons with multiple sclerosis (PwMS), particularly in relation to complex walking tasks. Objective. To determine the ability of PwMS to learn and retain a novel relationship between visual input and motor output - or visuomotor map - during visually guided walking. Methods. Nineteen PwMS and 17 healthy controls performed a precision walking task while adapting to prism lenses that altered the normal visuomotor map on 1 day, and again after a 1-week delay. The task required individuals to walk and step onto 2 targets without stopping. To quantify motor performance, we determined foot placement error relative to the targets. Results. PwMS with mild disability and healthy controls attenuated foot placement error over repeated trials when exposed to the novel mapping and demonstrated a similar rate and magnitude of adaptation in the first learning session. Both groups equally retained the adaptation 1 week later, reflected by reduced foot placement error and a faster rate of error reduction in that session. Conclusion. PwMS can learn and retain a novel visuomotor mapping during a precision-based walking task. This suggests that PwMS with mild disability have the capacity for short-term motor learning and retention, indicating that neural plasticity is preserved.