This study aims to optimize rTMS stimulation protocols for MDD by deterministically coupling the timing of TMS to the ongoing oscillatory neural activity in the underlying cortex as measured in real-time with high-density surface EEG. It is hypothesized that alpha phase-locked rTMS of the left DLPFC reverses increased alpha-band oscillatory activity and cortical hypo-excitability more efficiently than current open-loop rTMS protocols used in the treatment of MDD.