- Participants will have transcranial magnetic stimulations (TMS) at 2 places on the head. Two wire <TAB>coils will be held on the scalp. A brief electrical current creates a magnetic pulse that affects brain <TAB>activity. Muscles of the face, arm, or leg might twitch. Participants may have to tense certain muscles or do simple tasks during TMS. They may be asked to rate any discomfort caused by TMS.