TMS of parietal and occipital cortex locked to spontaneous transient large-scale brain states enhances natural oscillations in EEG

Yang Bai; Jie Xuan; Shihang Jia; Ulf Ziemann

doi:10.1016/j.brs.2023.10.008

TMS of parietal and occipital cortex locked to spontaneous transient large-scale brain states enhances natural oscillations in EEG

Brain Stimul. 2023 Nov-Dec;16(6):1588-1597. doi: 10.1016/j.brs.2023.10.008. Epub 2023 Oct 11.

Authors

Yang Bai¹, Jie Xuan², Shihang Jia², Ulf Ziemann³

Affiliations

¹ Department of Rehabilitation Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi, China; Rehabilitation Medicine Clinical Research Center of Jiangxi Province, 330006, Jiangxi, China; Department of Neurology & Stroke, University of Tübingen, Tübingen, Germany; Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany. Electronic address: baiyang1126@gmail.com.
² Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China.
³ Department of Neurology & Stroke, University of Tübingen, Tübingen, Germany; Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany. Electronic address: ulf.ziemann@uni-tuebingen.de.

PMID: 37827359
DOI: 10.1016/j.brs.2023.10.008

Abstract

Background: Fluctuating neuronal network states influence brain responses to transcranial magnetic stimulation (TMS). Our previous studies revealed that transient spontaneous bihemispheric brain states in the EEG, driven by oscillatory power, information flow and regional domination, modify cortical EEG responses to TMS. However, the impact of ongoing fluctuations of large-scale brain network states on TMS-EEG responses has not been explored.

Objectives: To determine the effects of large-scale brain network states on TMS-EEG responses.

Methods: Resting-state EEG and structural MRI from 24 healthy subjects were recorded to infer large-scale brain states. TMS-EEG was acquired with TMS at state-related targets, identified by the spatial distribution of state activation power from resting-state EEG. TMS-induced oscillations were measured by event-related spectral perturbations (ERSPs), and classified with respect to the brain states preceding the TMS pulses. State-locked ERSPs with TMS at specific state-related targets and during state activation were compared with state-unlocked ERSPs.

Results: Intra-individual comparison of ERSPs by threshold free cluster enhancement (TFCE) revealed that posterior and visual state-locked TMS, respectively, increased beta and alpha responses to TMS of parietal and occipital cortex compared to state-unlocked TMS. Also, the peak frequencies of ERSPs were increased with state-locked TMS. In addition, inter-individual correlation analyses revealed that posterior and visual state-locked TMS-induced oscillation power (ERSP clusters identified by TFCE) positively correlated with state-dependent oscillation power preceding TMS.

Conclusions: Spontaneous transient large-scale brain network states modify TMS-induced natural oscillations in specific brain regions. This significantly extends our knowledge on the critical importance of instantaneous state on explaining the brain's varying responsiveness to external perturbation.

Keywords: Event-related spectral perturbation; Natural frequency; Oscillatory brain state; TMS-EEG.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Electroencephalography* / methods
Healthy Volunteers
Humans
Magnetic Resonance Imaging
Occipital Lobe
Transcranial Magnetic Stimulation* / methods