Graph Analysis of TMS–EEG Connectivity Reveals Hemispheric Differences following Occipital Stimulation

• DOI: 10.3390/s23218833
• Publication Date: 2023-10-30T17:26:55Z
• Authors: Ilaria Siviero; Davide Bonfanti; Gloria Menegaz; Silvia Savazzi; Chiara Mazzi; Silvia Francesca ...
• Keywords: TMS-EEG; brain functional connectivity; Chemical technology; Brain functional connectivity; Graph analysis; Brain; Bayes Theorem; Electroencephalography; TP1-1185; TMS–EEG; Transcranial Magnetic Stimulation; Article; graph analysis; TEP; occipital stimulation; Humans; Occipital stimulation; Evoked Potentials

(1) Background: Transcranial magnetic stimulation combined with electroencephalography (TMS–EEG) provides a unique opportunity to investigate brain connectivity. However, possible hemispheric asymmetries in signal propagation dynamics following occipital TMS have not been investigated. (2) Methods: Eighteen healthy participants underwent single-pulse at two different EEG sites, corresponding early visual areas. We used state-of-the-art Bayesian estimation approach accurately estimate TMS-evoked potentials (TEPs) from data, which has previously this context. To capture the rapid of information flow patterns, we implemented self-tuning optimized Kalman (STOK) filter conjunction partial directed coherence (iPDC) measure, enabling us derive time-varying connectivity matrices. Subsequently, graph analysis was conducted assess key network properties, providing insight into overall organization network. (3) Results: Our findings revealed distinct lateralized effects on effective and networks after stimulation, left facilitating enhanced communication between contralateral frontal regions right promoting increased intra-hemispheric ipsilateral connectivity, as evidenced by statistical test (p < 0.001). (4) Conclusions: The identified differences terms provide novel insights involved processing, revealing specificity neural responses stimulation.