Changes in central EEG activity in relation to voluntary movement. II. Hemiplegic patients.

Publisher Summary This chapter discusses the changes in central electroencephalography (EEG) activity in relation to voluntary movement. In 5 patients with a low degree of left-hand hemiparesis, the transversal Bereitschaftspotential (BP) distribution is calculated for both hands. It is found that using the right hand for voluntary movement there is a clear maximal negativity over the contralateral hemisphere; pressing the paretic hand (left hand) the maximal negativity is on the ipsilateral side. On two patients with an infarct in the right hemisphere, it is demonstrated that the phasic desynchronization before and parallel with a voluntary hand movement is clearly reduced over the affected side. The infarct-related abnormal asymmetric EEG reactivity is reduced, regardless of which hand is used for movement. Beside the EEG reactivity also in the power spectra clear hemispheric differences could be seen. These abnormal EEG asymmetries are reduced with the neurological recovery of the patient. It is of interest that the abnormal asymmetric EEG reactions are also obtained when the conventional clinical EEG on visual analysis is reported as normal.