Thalamic Control Over Laminar Cortical Dynamics Across Conscious States

Muller, E. J.; Munn, B.; Baracchini, G.; Fulcher, B. D.; Medel, V.; Redinbaugh, M. J.; Saalmann, Y. B.; Brunton, B. W.; Brunton, S. L.; Shine, J.

doi:10.1101/2024.07.02.601788

bioRxiv · 10.1101/2024.07.02.601788

Thalamic Control Over Laminar Cortical Dynamics Across Conscious States

Muller, E. J.·Munn, B.·Baracchini, G.·Fulcher, B. D.·Medel, V.·Redinbaugh, M. J.·Saalmann, Y. B.·Brunton, B. W.·Brunton, S. L.·Shine, J.

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Abstract

The human brain must support both stable and flexible neural dynamics in order to adapt to changing contexts that are inherently non-linear. The thalamus has been linked to the coordination of these opposing dynamical regimens in the cerebral cortex, however existing methodological approaches have not integrated sufficient neurobiological details with a sensitive measure of neural dynamics that permits sensitivity to time-series non-linearities. Inspired by the field of fluid dynamics, we use a novel approach to show that spontaneous fMRI data exhibits non-trivial fluctuations in predictability over time, akin to a river that has sections of smooth and predictable (laminar) versus rough and unpredictable (non-laminar) fluid flow. We use a combination of pharmacological fMRI, macaque electrophysiology and a large-scale biophysical model of the thalamocortical system to provide robust evidence that the thalamus provides versatile control over globally linear dynamics in the cerebral cortex that characterize conscious states.

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Muller, E. J., Munn, B., Baracchini, G., Fulcher, B. D., Medel, V., Redinbaugh, M. J., Saalmann, Y. B., Brunton, B. W., Brunton, S. L., Shine, J.. 2024-07-03. Thalamic Control Over Laminar Cortical Dynamics Across Conscious States. https://doi.org/10.1101/2024.07.02.601788

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