Classification of EEG Signals Reveals a Focal Aftereffect of 10 Hz Motor Cortex Transcranial Alternating Current Stimulation. Issue 1 (7th January 2022)

• Record Type: Journal Article
• Authors: Tzvi, Elinor; Alizadeh, Jalal; Schubert, Christine; Classen, Joseph
• Is Part Of: Cerebral cortex communications. Volume 3:Issue 1(2022)
• Publication Date: 2022-01-07
• Subjects: classification -- EEG -- machine learning -- motor network -- transcranial alternating current stimulation; Cerebral cortex -- Periodicals; Brain -- Periodicals; 612.825
• DOI: 10.1093/texcom/tgab067
• Languages: English
• ISSNs: 2632-7376

Abstract

Abstract: Transcranial alternating current stimulation (tACS) modulates oscillations in a frequency- and location-specific manner and affects cognitive and motor functions. This effect appears during stimulation as well as "offline, " following stimulation, presumably reflecting neuroplasticity. Whether tACS produces long-lasting aftereffects that are physiologically meaningful, is still of current debate. Thus, for tACS to serve as a reliable method for modulating activity within neural networks, it is important to first establish whether "offline" aftereffects are robust and reliable. In this study, we employed a novel machine-learning approach to detect signatures of neuroplasticity following 10-Hz tACS to two critical nodes of the motor network: left motor cortex (lMC) and right cerebellum (rCB). To this end, we trained a classifier to distinguish between signals following lMC-tACS, rCB-tACS, and sham. Our results demonstrate better classification of electroencephalography (EEG) signals in both theta (θ, 4–8 Hz) and alpha (α, 8–13 Hz) frequency bands to lMC-tACS compared with rCB-tACS/sham, at lMC-tACS stimulation location. Source reconstruction allocated these effects to premotor cortex. Stronger correlation between classification accuracies in θ and α in lMC-tACS suggested an association between θ and α efffects. Together these results suggest that EEG signals over premotor cortex contains unique signatures of neuroplasticity following 10-Hz motor cortex tACS.