(13, 15). On the other hand, PAC strength derived from scalp EEG did not differ between patients in the off-medication state and healthy controls during a verbally cued intermittent hand-opening/closing task (14). This inconsistency may reflect differences in the characteristics of concomitantly recorded movements. In addition, it is not clear from these reports whether movement-related PAC was derived from signals recorded during the execution of kinematically normal or abnormal movements (8, 14, 15). Because abnormalities of movement-related PAC may not become apparent until kinematic abnormalities occur, the lack of information on kinematics renders the involvement of PAC unknown, concerning the pathophysiology of movement disorders.
