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bioRxiv · 10.1101/2021.07.13.451709

Effects of sub-threshold transcutaneous auricular vagus nerve stimulation on cerebral blood flow

Chen, C.·Mao, Y.·Falahpour, M.·MacNiven, K. H.·Heit, G.·Sharma, V.·Alataris, K.·Liu, T. T.
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Abstract

BackgroundTranscutaneous auricular vagus nerve stimulation (taVNS) has shown promise as a non-invasive alternative to vagus nerve stimulation (VNS) with implantable devices, which has been used to treat drug-resistant epilepsy and treatment-resistant depression. Prior work has used functional MRI to investigate the brain response to taVNS, and more recent work has also demonstrated potential therapeutic effects of high-frequency sub-threshold taVNS in rheumatoid arthritis. However, no studies to date have measured the effects of high-frequency sub-threshold taVNS on cerebral blood flow (CBF). Objective/HypothesisThe objective of this study was to determine whether high-frequency (20 kHz) sub-threshold taVNS induces significant changes in CBF. MethodsArterial spin labeling (ASL) MRI scans were performed on 20 healthy subjects in a single-blind placebo-controlled repeated measures experimental design. The ASL scans were performed before and after 15 minutes of either sub-threshold taVNS treatment or a sham control. ResultstaVNS induced significant changes in CBF in the superior posterior cerebellum that were largely localized to bilateral Crus I and Crus II. Post hoc analyses showed that the changes were driven by a treatment-related decrease in CBF. ConclusionsFifteen minutes of high-frequency sub-threshold taVNS can induce sustained CBF decreases in the bilateral posterior cerebellum in a cohort of healthy subjects. This study lays the foundation for future studies in clinical popluations to assess whether similar effects can be observed and are related to treatment outcomes.

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Chen, C., Mao, Y., Falahpour, M., MacNiven, K. H., Heit, G., Sharma, V., Alataris, K., Liu, T. T.. 2021-07-14. Effects of sub-threshold transcutaneous auricular vagus nerve stimulation on cerebral blood flow. https://doi.org/10.1101/2021.07.13.451709

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