Closed-loop phase-locked rTMS treatment decreases global cortical excitability in major depressive disorder patients

Abstract Repetitive transcranial magnetic stimulation (rTMS) has been shown to be an effective treatment for major depressive disorder (MDD). Although considerable clinical data have supported its efficacy, exact mechanism of action and optimal combination parameters remains unclear. Recent research suggests that the delivery rTMS causes long-term inhibition excitation neurons in varied brain areas. Additionally, interest steadily grown using neurophysiologic measures cortical excitability as a biomarker outcomes MDD. Under hypothesis EEG alpha phase is index across or within network, our group developed novel closed-loop system where pulse train can triggered at specific each patient's prefrontal rhythm optimize outcomes. Twenty-four MDD patients were randomly assigned either synchronized unsynchronized beginning treatment. Changes global mean field power used characterize response administration. During six-week daily period, we observed changes quasi-alpha band (6-13 Hz) rest are related both groups. Notably, received showed higher decreases after session compared group. More importantly, group, weeks with greater decrease Hamilton Rating Scale Depression significant paired (before vs. treatment) decreases. Our findings provide additional evidence rTMS, serve reliable Moreover, phase-locking induce reduction excitability, thus might help increase efficacy. Research Category Technology Methods Clinical Research: 10. Transcranial Magnetic Stimulation (TMS) Keywords: MDD, EEG-synchronization,