Motor training. Participants perform a pinching movement once every other second, timed to a metronome, during rTMS. For TMS, a wire coil is held on the subject's scalp. A brief electrical current is passed through the coil, creating a magnetic pulse that stimulates the brain. The subject hears a click and may feel a pulling sensation on the skin under the coil. There may be a twitch in the muscles of the face, arm or leg. rTMS involves repeated magnetic pulses delivered in short bursts of impulses.