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bioRxiv · 10.1101/2022.09.28.509893

A Simple Model of Cortical Intraregional Metastability

Venkadesh, S.·Shaikh, A.·Shakeri, H.·Henry, T. R.·Barreto, E.·Van Horn, J. D.
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Abstract

Transient synchronization of bursting activity in neural networks, which occurs in patterns of metastable phase relationships between neurons, is a notable feature of network dynamics observed in vivo. However, the mechanisms that contribute to this dynamical complexity in neural circuits are not well understood. Local circuits in cortical regions consist of populations of neurons with diverse intrinsic oscillatory features. In this study, we numerically show that the phenomenon of transient synchronization, also referred to as metastability, emerges in an inhibitory neural population when the neurons intrinsic fast-spiking dynamics are appropriately modulated by slower inputs from an excitatory neural population. Using a compact model of a mesoscopic-scale network consisting of excitatory pyramidal and inhibitory fast-spiking neurons, our work demonstrates a relationship between the frequency of neural oscillations and the features of emergent metastability. In addition, a novel metric is formulated to characterize collective transitions in metastable networks. Finally, we discuss a blueprint to model the whole-brain resting-state dynamics using our scalable representation of intraregional network metastability.

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Venkadesh, S., Shaikh, A., Shakeri, H., Henry, T. R., Barreto, E., Van Horn, J. D.. 2022-09-30. A Simple Model of Cortical Intraregional Metastability. https://doi.org/10.1101/2022.09.28.509893

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