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bioRxiv · 10.1101/2024.08.15.607985

Personalized whole-brain activity patterns predict human corticospinal tract activation in real-time

Khatri, U.·Pulliam, K.·Manesiya, M.·Cortez, M. V.·Millan, J. d. R.·Hussain, S.
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Abstract

BACKGROUNDTranscranial magnetic stimulation (TMS) interventions could feasibly treat stroke-related motor impairments, but their effects are highly variable. Brain state-dependent TMS approaches are a promising solution to this problem, but inter-individual variation in lesion location and oscillatory dynamics can make translating them to the poststroke brain challenging. Personalized brain state-dependent approaches specifically designed to address these challenges are therefore needed. METHODSAs a first step towards this goal, we tested a novel machine learning-based EEG-TMS system that identifies personalized brain activity patterns reflecting strong and weak corticospinal tract (CST) output (strong and weak CST states) in healthy adults in real-time. Participants completed a single-session study that included the acquisition of a TMS-EEG-EMG training dataset, personalized classifier training, and real-time EEG-informed single pulse TMS during classifier-predicted personalized CST states. RESULTSMEP amplitudes elicited in real-time during personalized strong CST states were significantly larger than those elicited during personalized weak and random CST states. MEP amplitudes elicited in real-time during personalized strong CST states were also significantly less variable than those elicited during personalized weak CST states. Personalized CST states lasted for [~]1-2 seconds at a time and [~]1 second elapsed between consecutive similar states. Individual participants exhibited unique differences in spectro-spatial EEG patterns between personalized strong and weak CST states. CONCLUSIONOur results show for the first time that personalized whole-brain EEG activity patterns predict CST activation in real-time in healthy humans. These findings represent a pivotal step towards using personalized brain state-dependent TMS interventions to promote poststroke CST function.

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Khatri, U., Pulliam, K., Manesiya, M., Cortez, M. V., Millan, J. d. R., Hussain, S.. 2024-08-19. Personalized whole-brain activity patterns predict human corticospinal tract activation in real-time. https://doi.org/10.1101/2024.08.15.607985

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