Principal investigator (Dr. Sporn) left the sponsoring institution.

This study is a trial of low frequency Repetitive Transcranial magnetic stimulation( rTMS) for subjects with autism spectrum disorders, specially targeting repetitive behaviors.

This project is a 3-week double blind cross-over trial for adolescents and adults who meet criteria for autism and have clinically prominent repetitive behaviors. The investigator will apply low frequency rTMS for 20 minutes 5 times a week for 3 weeks targeting the area of brain which was involved in repetitive behaviors. The investigator will obtain clinical measures of repetitive behaviors as well as social functioning pre and post treatment. As a control and a cross-over condition , we will stimulate other area of brain which has nothing to do with repetitive behaviors but may improve social functioning in autism spectrum disorders. In addition to r TMS we will perform a pre and post treatment perfusion functional MRI and obtain TMS measure of excitability of brain.

Inclusion Criteria:

1. English Speaking
2. Capacity to give consent and sign HIPAA Authorization
3. Patients currently taking psychotropic medications must be at the same stable dose and likely to be able to continue at the same dose throughout the study
4. ASD diagnosis according to the DSM-IV TR Symptom and Criterion checklist for ASD
5. Significant level of repetitive behaviors to distinguish from movement disorders to be in at least 3 out of 6 sub-scales (stereotyped behavior, self-injurious behavior, compulsive behavior, ritualistic behavior, sameness behavior, restricted behavior) -

Exclusion Criteria:

1. Women of child-bearing potential not using birth control, pregnant or breast feeding
2. H/o Bipolar Disorder (lifetime), any Psychotic Disorder (lifetime) history of Major Depressive Disorder or of substance abuse or dependence within the past year
3. Significant sub-average intellectual function (IQ<70)
4. Intracranial implants
5. Increased risk of seizure for any reason, including prior diagnosis of epilepsy, seizure disorder, febrile seizure, increased intracranial pressure or history of significant head trauma with loss of consciousness for > 5 minutes.
6. Current significant laboratory abnormality
7. Neurological disorder including but not limited to space occupying brain lesion, any history of seizures, history of cerebrovascular accident, fainting, cerebral aneurysm, dementia, Huntington chorea, Multiple Sclerosis -