Treatment of Depression With Connectivity Guided Robotically Delivered rTMS

The investigators propose a randomized, double-blind, 4-week trial of TMS to the left dorsolateral prefrontal cortex (DLPFC) for subjects with MDD all of whom at the patient's treatment clinic are concurrently receiving pharmaceutical and psychotherapeutic interventions. Arm 1 delivers active rTMS to the left DLPFC using the standard aiming strategy. Arm 2 delivers active rTMS to the left anterior DLPFC using connectivity-based, image-guided aiming. Arm 3 delivers active rTMS to the left posterior DLPFC using connectivity-based, image-guided aiming. In all three arms, rTMS is administered in an image-guided, robotically-positioned TMS (irTMS) manner to ensure therapist blinding and equivalent subject experiences across arms. In all three arms, the following stimulation protocol will be used: 10 Hz irTMS delivered in 4 sec trains with 26 sec inter-train intervals, 37.5 minutes/session (i.e. 3,000 pulses/session), 5 sessions/week, for 4 weeks. Neuroimaging will be used both for treatment planning and to characterize any TMS-induced network plasticity using resting-state functional magnetic resonance imaging (rs-fMRI) at week 4 of each treatment arm. Clinical assessments will be administered weekly throughout treatment (weeks 1-4) at the patient's treatment clinic. Additional psychological tests will be performed at UT Health-San Antonio's Research Imaging Institute (RII) at the baseline and post-treatment visits in order to track patient progress.