Investigating the Effects of Auditory and Vibrotactile Rhythmic Sensory Stimulation on Depression: An EEG Pilot Study

Abdullah A Mosabbir; Thenile Braun Janzen; Maryam Al Shirawi; Susan Rotzinger; Sidney H Kennedy; Faranak Farzan; Jed Meltzer; Lee Bartel

doi:10.7759/cureus.22557

Investigating the Effects of Auditory and Vibrotactile Rhythmic Sensory Stimulation on Depression: An EEG Pilot Study

Cureus. 2022 Feb 24;14(2):e22557. doi: 10.7759/cureus.22557. eCollection 2022 Feb.

Authors

Abdullah A Mosabbir¹, Thenile Braun Janzen², Maryam Al Shirawi³, Susan Rotzinger³, Sidney H Kennedy⁴, Faranak Farzan⁵, Jed Meltzer¹, Lee Bartel²

Affiliations

¹ Rotman Research Institute, Baycrest Health Sciences, Toronto, CAN.
² Faculty of Music, University of Toronto, Toronto, CAN.
³ Department of Psychiatry, University Health Network, Toronto, CAN.
⁴ Centre for Depression and Suicide Studies, St. Michael's Hospital, Toronto, CAN.
⁵ School of Mechatronic Systems Engineering, Simon Fraser University, Surrey, CAN.

Abstract

Background Major depressive disorder (MDD) is a persistent psychiatric condition and one of the leading causes of global disease burden. In a previous study, we investigated the effects of a five-week intervention consisting of rhythmic gamma frequency (30-70 Hz) vibroacoustic stimulation in 20 patients formally diagnosed with MDD. In that study, the findings suggested a significant clinical improvement in depression symptoms as measured using the Montgomery-Asberg Depression Rating Scale (MADRS), with 37% of participants meeting the criteria for clinical response. The goal of the present research was to examine possible changes from baseline to posttreatment in resting-state electroencephalography (EEG) recordings using the same treatment protocol and to characterize basic changes in EEG related to treatment response. Materials and methods The study sample consisted of 19 individuals aged 18-70 years with a clinical diagnosis of MDD. The participants were assessed before and after a five-week treatment period, which consisted of listening to an instrumental musical track on a vibroacoustic device, delivering auditory and vibrotactile stimulus in the gamma-band range (30-70 Hz, with particular emphasis on 40 Hz). The primary outcome measure was the change in Montgomery-Asberg Depression Rating Scale (MADRS) from baseline to posttreatment and resting-state EEG. Results Analysis comparing MADRS score at baseline and post-intervention indicated a significant change in the severity of depression symptoms after five weeks (t = 3.9923, df = 18, p = 0.0009). The clinical response rate was 36.85%. Resting-state EEG power analysis revealed a significant increase in occipital alpha power (t = -2.149, df = 18, p = 0.04548), as well as an increase in the prefrontal gamma power of the responders (t = 2.8079, df = 13.431, p = 0.01442). Conclusions The results indicate that improvements in MADRS scores after rhythmic sensory stimulation (RSS) were accompanied by an increase in alpha power in the occipital region and an increase in gamma in the prefrontal region, thus suggesting treatment effects on cortical activity in depression. The results of this pilot study will help inform subsequent controlled studies evaluating whether treatment response to vibroacoustic stimulation constitutes a real and replicable reduction of depressive symptoms and to characterize the underlying mechanisms.

Keywords: depression; electroencephalography; gamma stimulation; rhythmic sensory stimulation; vibroacoustic stimulation; vibrotactile.

Grants and funding

This research was conducted with financial support from CAN-BIND. CAN-BIND is an Integrated Discovery Program carried out in partnership with, and financial support from, the Ontario Brain Institute, an independent nonprofit corporation, funded partially by the Ontario Government. The opinions, results, and conclusions are those of the authors, and no endorsement by the Ontario Brain Institute is intended or should be inferred. Additional funding was provided by the Connaught Fund, University of Toronto.