Acute effect of vagus nerve stimulation (VNS) on brain function

Erhan Kavakbasi; Joachim Gross; Andreas Wollbrink; Ruth Fellmeth; Bernhard T Baune

doi:10.1016/j.jpsychires.2021.06.042

Acute effect of vagus nerve stimulation (VNS) on brain function

J Psychiatr Res. 2021 Sep:141:136-139. doi: 10.1016/j.jpsychires.2021.06.042. Epub 2021 Jun 24.

Authors

Erhan Kavakbasi¹, Joachim Gross², Andreas Wollbrink², Ruth Fellmeth³, Bernhard T Baune⁴

Affiliations

¹ Department of Psychiatry, University Hospital Münster, University of Münster, Münster, Germany. Electronic address: erhan.kavakbasi@ukmuenster.de.
² Institute for Biomagnetism and Biosignalanalysis, University Hospital Muenster, University of Münster, Münster, Germany.
³ Department of Psychiatry, University Hospital Münster, University of Münster, Münster, Germany.
⁴ Department of Psychiatry, University Hospital Münster, University of Münster, Münster, Germany; Department of Psychiatry, Melbourne Medical School, The University of Melbourne, Melbourne, Australia; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia.

PMID: 34198194
DOI: 10.1016/j.jpsychires.2021.06.042

Abstract

Introduction: VNS is a non-pharmalogical neuromodulatory treatment option for difficult-to-treat depression. A pulse generator implanted in the left chest area is connected to an electrode that is wrapped around the left vagal nerve. It is presumed, that the vagal afferent network modulates neuronal activity in key monoaminergic structures.

Methods: We performed MEG recording during active stimulation of the left vagal nerve. Our patient was a 60 years old female treated with VNS since December 2019 due to unipolar major depression.

Results: MEG recording and analysis were possible despite stimulation signals and the metal stimulation systems. We saw a reproducible reduction of the 10-Hz-alpha amplitude after the end of the 30 s stimulation period in wide-spread areas including parieto-occipital cortex where alpha oscillations are prominently generated. During stimulation, however, alpha oscillations remained unaffected. These findings could be reproduced in a second measurement.

Conclusion: Increased alpha power was linked to depressive states and alterations of cortical activity. A reduction may indicate cortical activation by stimulation of the vagal nerve as a possible mechanism of action of VNS in depression.

Keywords: DTD; Difficult-to-treat depression; MEG; Magnetoencephalography; TRD; Treatment-resistant depression; VNS; Vagus nerve stimulation.

MeSH terms

Brain / diagnostic imaging
Depressive Disorder, Major* / therapy
Female
Humans
Middle Aged
Vagus Nerve
Vagus Nerve Stimulation*