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bioRxiv · 10.1101/2024.10.30.621153

Multiscale excitation-inhibition balance dynamics: integrating metabolite kinetics with time-varying executive networks

Abstract

The balance between neural excitation and inhibition (EIB) is an essential mechanism supporting cognitive processes. Yet, little is understood about how EIB shifts with cognitive load and its impact on functional connectivity dynamics. In this study, we investigate temporal profiles of the reciprocal modulation between EIB and functional network dynamics during working memory tasks, revealing that EIB prefrontal kinetics scale with increasing cognitive load. Notably, prefrontal EIB kinetics correlated with cognitive load, impacting stability of networks crucial for cognitive function. On one hand, brain dynamics adapt to meet increasing cognitive challenges with a shift towards more focused and sustained neural activity patterns in terms of connectivity. On the other, imbalances favouring excitation may hinder cognitive adaptability. Importantly, this experimental approach demonstrates a link between EIB kinetics, brain network dynamics and cognitive performance, defining the groundwork for exploring healthy and aberrant cognitive states. TeaserHighly focused or less responsive? Chemical signalling and network dynamics are coupled to produce persistent cognitive states.

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Saviola, F., Tambalo, S., Beghini, L., Ferrari, A., Cassone, B., Van De Ville, D., Jovicich, J.. 2024-10-31. Multiscale excitation-inhibition balance dynamics: integrating metabolite kinetics with time-varying executive networks. https://doi.org/10.1101/2024.10.30.621153

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