Clinical Trial: Study of Repetitive Transcranial Magnetic Stimulation in Parkinson's DiseaseThis study will examine the effects of repetitive transcranial magnetic stimulation (rTMS) on Parkinson's disease symptoms. rTMS is a way of stimulating the brain that may be able to change the electrical activity of the nerve cells in the brain. It has been proposed as a treatment for brain disorders, including Parkinson's disease. In preliminary studies, some patients' symptoms improved; in some they worsened temporarily, and some showed no change.