In this study, Dr. Sporn is planning to use transcranial magnetic stimulation (TMS) to stimulate a specific region of the brain in order to treat repetitive behaviors. This strategy has been helpful in patients with obsessive compulsive disorder and Tourette's syndrome, two psychiatric conditions that also exhibit repetitive behaviors. Adolescents and adults (ages 13 to 35) will be recruited and treatment will include sessions lasting 20 minutes, 5 days a week, for 3 weeks. This is a double-blind study, so the investigators will stimulate either the target area or another brain area, which is not likely to produce benefit in repetitive behaviors but may improve social functioning. Patients who do not improve after the first 3 weeks of treatment will be offered an opportunity to cross-over into another condition (stimulating the other area of the brain). The patients will also undergo an extensive clinical evaluation and magnetic resonance imaging that will be done before and after the study.