Technique to investigate ipsilateral functional activation in motor task

This paper describes a technique to investigate in hemiplegic subjects the effect of cerebral lesions on motor learning with the unimpaired arm. Robot-aided functional imaging experiments suggest that the ipsilateral hemisphere plays a role during learning of a motor task involving the ipsilateral arm. Hemiplegic subjects thus provide an opportunity to test: (a) the effect of cerebral lesions during motor learning, and (b) whether the measured significant changes in neural activity during imaging experiments are not artifacts. The authors' results demonstrate the role of selected ipsilateral brain structures during motor learning. For example, ipsilateral right temporal lesions affect motor performance and learning. Lesions in the motor strip area do not adversely affect motor learning with the unimpaired arm. These results have implications for general rehabilitation strategies that presently do not recognize this deficit.