Learning interference in dynamic manipulation with redundant degrees of freedom

One important dimension of sensorimotor rehabilitation is motor practice to induce adaptation to new and improved movement patterns. Previous studies have shown that motor adaptation in a novel, directional dynamic context induces interference on the learning of a subsequent task. However, little data exist about how such interference affects the low-level coordination pattern of the end-effectors in the presence of biomechanical redundancy. We addressed this question by using a novel experimental design based on velocity-dependent torque perturbations delivered by haptic devices during three-finger dynamic manipulation tasks. We found that the finger force patterns in the initial stages after context switch was modulated by the preceding contexts, exhibiting higher energy cost. These findings provide insights to improving protocols for sensorimotor rehabilitation.