Imaging- vs. Scalp-Targeted Accelerated TMS for Depression: The Number Needed to Scan Trial

Inclusion Criteria: * Age 22-80 * English proficiency sufficient for informed consent, questionnaires/tasks, and treatment * Primary diagnosis of major depressive disorder per DSM-V criteria (Quick Structured Clinical Interview for DSM-5) * \>20 on Beck Depression Inventory (BDI) * \>20 on the Montgomery-Åsberg Depression Rating Scale (MADRS) * Moderate to severe level of treatment resistance (Maudsley Staging Method) * Stable antidepressant medication regimen, or remain medication free, for 4 weeks prior to treatment and to remain on this regimen throughout the study until the 1-month post-treatment visit. * Primary clinician (e.g. psychiatrist, therapist, psychologist, APRN, PA, etc.) responsible for psychiatric care before, during, and after the trial * Agreement to lifestyle considerations * Abstain from becoming pregnant from screening to one-month after treatment (the MRI visit) * Continue usual intake patterns of caffeine- or xanthine-containing products (e.g. coffee, tea, soft drinks, chocolate) throughout treatment * Abstain from alcohol, tobacco, and recreational drugs for at least 24 hours before the start of each MRI and TMS session