Resonant Frequency rTMS: A Novel Approach to Target Circuit Modulation in Major Depressive Disorder

The purpose of the study is to develop a more personalized brain stimulation using repetitive transcranial magnetic stimulation or rTMS approach to treat major depressive disorder (MDD). The investigators had previously developed a personalized rTMS treatment by examining the effectiveness of different rTMS frequency from 5 to 18 Hertz (Hz). The optimal treatment frequency is termed resonance frequency and varies across individuals. There has not been a systematic method to identify the best stimulation frequency in an individual-specific way. In this project, the investigators will identify and compare 3 rTMS frequencies, all targeting the brain region called left dorsolateral prefrontal cortex (DLPFC): 1 that engages brain circuit connectivity the most- the investigators call this resonant frequency (RF)-max (RF-max), 1 that is the lowest ranked resonance frequency called RF-min and 1 that is standard of care treatment - rTMS of 10 Hz as a point of comparison. This study is a multi-sites project that will be conducted at UCLA and Butler hospital. This study will enroll 84 participants with MDD over the course of 4.5 years. Participants will undergo a brain imaging scan or magnetic resonance imaging (MRI), 3 electroencephalograms (or EEG, a measurement of electrical activity of the brain), to identify rTMS resonance frequencies (RFs), 3 sessions of different resonant frequencies of rTMS in combination with EEG, totaling up to 7 in person visits. Participation will take up to 4 weeks.