Change in Movement-Related Cortical Potentials Following Constraint-Induced Movement Therapy (CIMT) After Stroke

Patients with chronic stroke were given Constraint-Induced Movement Therapy (CIMT) over an intensive two-week course of treatment. The intervention resulted in a large improvement in use of the more-affected upper extremity in the laboratory and in the real-world environment. High-resolution electroencephalography (EEG) showed that the treatment produced marked changes in cortical activity that correlated with the significant rehabilitative effects. Repetitive unilateral self-paced voluntary movements showed a large increase after treatment in the amplitudes of the late components of the Bereitschaftspotential (BP) both in the hemisphere contralateral to the more-affected arm and in the ipsilateral hemisphere. Simultaneous electromyographic recordings (EMG) and other aspects of the data indicate that the emergence of the movement-related neural source in the healthy hemisphere was not due to mirror movements of the non-test hand and that the increase in BP amplitudes was not the result of an increase in the force or effort of the response pre- to post-treatment. The results are consistent with the rehabilitation treatment having produced a use-dependent cortical reorganization and is a case where the physiological data interdigitates with and provides additional credibility to the clinical data.