Effects of transcranial magnetic stimulation on voluntary thumb movement

In this study, the effect of the transcranial magnetic stimulation (TMS) on the continuous voluntary movement of the finger was investigated. We measured the trajectory of the thumb tip and electromyogram (EMG) of the hand and forearm muscles after the TMS of the primary motor cortex area (M1) during continuous voluntary rotation of the thumb. The results showed that the velocity of the thumb tip was accelerated right after the TMS followed by the deceleration. It was indicated that enhance and suppression of the muscle activity by the TMS resulted in the change of the finger velocity in the voluntary movement.