Enhanced visual error in a coordinated pinch task

Our previous work has shown that visual distortion of subject-controlled goals can be used to manipulate force production and movement distance. Thus, visual distortion may be a helpful addition to robotic rehabilitation for brain-injured and stroke patients. In this work, we investigated the effects of distortion on unimpaired subjects learning a two-finger coordinated pinch task. Rather than distorting the subject´s goal, we enhanced the apparent error attributable to one or both fingers. Distortion affected the distribution of attention between the two fingers; when the error enhancement was given to one finger, the performance of that finger improved relative to the other. This result indicates that enhanced visual error could be used to manipulate the performance and the coordination pattern between fingers to achieve desired movements during rehabilitation