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Presentation Time: 11:55-12:15
Home University:
Research Mentor: Rachel Force, Psychiatry
Program: SURF
Research Title: Use of Transcranial Alternating Current Stimulation for the Treatment of Major Depressive Disorder

Major depressive disorder (MDD) is a common, severe psychiatric illness that has a lifetime prevalence of about 16.6% in adults. Patients with major depression respond to antidepressant drugs; however, approximately one-third of these patients remain treatment-resistant after adequate trials of multiple monoamine-based therapies. Treatment-resistant depression is a difficult condition to treat and has an impact on medical comorbidities such as heart disease, cancer, thyroid disease, manifestations of impending relapse, and genetic vulnerability. To combat this, we wanted to further explore the efficacy of alternative treatment methods with transcranial alternating current stimulation (tACS).

MDD has been associated with increased alpha oscillations (8-12 Hz) in the left dorsolateral prefrontal cortex. Therefore, targeting and reducing alpha oscillations in this area could prove beneficial to patients with MDD. Targeted stimulation modalities, such as tACS, can directly engage and selectively modulate oscillations through the application of weak electric currents to the scalp. In addition, tACS has mild side effects, and no serious adverse events have yet been reported. A recent pilot study showcased the preliminary efficacy of tACS to decrease alpha oscillations, but the neurophysiological mechanism of action of how tACS caused this change is still unclear.

This presentation will showcase how we hope to better understand the mechanism of action of tACS in MDD patients. This can be primarily understood with high-density EEG measurements taken before and after every stimulation session. For this study, eligible patients will participate in 5 consecutive 40-minute tACS stimulation sessions, with either sham or 10Hz (alpha) stimulation. In addition to the stimulation session, I will help collect eyes open Resting-State EEG (RSEEG) recordings immediately before and after the 40-minutes of stimulation. This will help determine the immediate after-effects of tACS on brain activity, specifically on alpha oscillation power. If a direct relationship between tACS and alpha power is established, then noninvasive therapies can be considered as a reliable treatment option to alleviate symptoms several symptoms in MDD patients.