Repetitive Versus Deep Transcranial Magnetic Stimulation for Major Depression

Inclusion Criteria: * Diagnosis of Major Depressive Disorder, at least moderate intensity, single or recurrent episode * HRSD-17 score of at least 18 * No improvement to at least two adequate courses of antidepressants (based on the ATHF) or were unable to tolerate at least two separate trials of antidepressants of inadequate dose and duration * On a stable antidepressant regimen for the past four weeks before screening * Patients with a chronic depressive episode \>2 years and who have previously received ECT or ketamine will be eligible to participate Exclusion Criteria: * Having previously received TMS; * Substance use disorder within the last three months * Diagnosis of bipolar or psychosis spectrum disorder * Anxiety or personality disorder that is assessed by a study investigator to be the primary cause and causing greater impairment than MDD * Concomitant major unstable medical or neurological illness * Intracranial implant, cardiac pacemaker or implanted medication pump * Significant laboratory abnormality; * Active suicidal intent * Pregnancy * If participating in psychotherapy, must have been in stable treatment for at least three months before entry into the study, with no anticipation of change * Currently taking more than the equivalent of 2 mg of lorazepam of a benzodiazepine daily or any dose of an anticonvulsant due to the potential to limit TMS effectiveness