Motor adaptation during redundant tasks with the wrist

Abstract

Abstract-This study analyzes motor adaptation during a redundant tasks with the wrist. The goal is threefold: (i) understanding if motor adaptation also occurs when CNS is involved in the solution of the redundancy problem; (ii) addressing whether motor strategies used to solve redundancy (i.e Donders' law) are disrupted or not during adaptation; (iii) verifying if motor strategies remain the same during adaptation and washout or they themselves adapt. First of all, our data confirm that CNS adapts its movements to the perturbation also when it is committed in the execution of a redundant task. Secondly, we showed that motor strategies used to solve redundancy (i.e Donders' law) are not disrupted during adaptation, since absolute values of thickness during the whole protocol remain in the range of physiological values. Lastly, analysis of the curvature of Donders' surfaces suggests that motor strategies, such as Donders' law, remain invariant during motor adaptation in redundant tasks.

A McKibben muscle arm learning equilibrium postures

“…Remarkably, the results also suggest that these two computational mechanisms allow a first gross solution to cope with load compensation. In this respect, the role of the sensed load is to passively modulate the biceps compliance avoiding the use of more complicated solutions based for example on internal models which could be developed by the organism in further developmental stages [35].…”