MOTOR IMAGERY ACTIVATES PRIMARY SENSORIMOTOR AREA IN HUMANS

The spatiotemporal patterns of Rolandic mu and beta rhythms were studi ed during motor imagery with a dense array of EEG electrodes. The subj ects were instructed to imagine movements of either the right or the l eft hand, corresponding to visual stimuli on a computer screen. It was found that unilateral motor imagery results in a short-lasting and lo calized EEG change over the primary sensorimotor area. The Rolandic rh ythms displayed an event-related desynchronization (ERD) only over the centralateral hemisphere. In two of the three investigated subjects, an enhanced Rolandic rhythm was found over the ipsilateral side. The p attern of EEG desynchronization related to imagination of a movement w as similar to the pattern during planing of a voluntary movement. (C) 1997 Published by Elsevier Science Ireland Ltd.