Differences in neural strategies explain exoskeleton-related benefits in performance over time during complex visuomotor wiring tasks

Abstract

This study evaluated the effects of a passive shoulder exoskeleton on neural, muscular, and perceptual responses during a three-day visuomotor wiring task involving overhead reaching. The task required participants to sequentially connect 40 randomly arranged targets on a two-dimensional board using a wire, engaging both motor and cognitive processes such as working memory and visual search. Twenty-four novice participants, balanced by sex, were randomly assigned to either an exoskeleton or a control group. The exoskeleton group demonstrated reduced upper extremity muscle activity but increased lower back activity. Despite similar perceived exertion levels between the groups, exoskeleton users reported lower mental demands, quicker visual searches, and higher task accuracy over time, all while exhibiting comparable task completion times. Neural analysis revealed greater functional specialization in the exoskeleton group, whereas the control group prioritized fronto-motor network integration. These findings provide valuable insights for practitioners contemplating the implementation of exoskeletons for tasks requiring both physical and cognitive engagement effort.