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bioRxiv · 10.1101/2020.07.08.193334

Mesoscale brain dynamics reorganizes and stabilizes during learning

Yaroslav Sych·Aleksejs Fomins·Leonardo Novelli·Fritjof Helmchen
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Abstract

Adaptive behavior is coordinated by neuronal networks that are distributed across multiple brain regions. How cross-regional interactions reorganize during learning remains elusive. We applied multi-fiber photometry to chronically record simultaneous activity of 12-48 mouse brain regions while mice learned a tactile discrimination task. We found that with learning most regions shifted their peak activity from reward-related action to the reward-predicting stimulus. We corroborated this finding by functional connectivity estimation using transfer entropy, which revealed growth and stabilization of mesoscale networks encompassing basal ganglia, thalamus, cortex, and hippocampus, especially during stimulus presentation. The internal globus pallidus, ventromedial thalamus, and several regions in frontal cortex emerged as hub regions. Our results highlight the cooperative action of distributed brain regions to establish goal-oriented mesoscale network dynamics during learning.

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Yaroslav Sych, Aleksejs Fomins, Leonardo Novelli, Fritjof Helmchen. 2020-07-08. Mesoscale brain dynamics reorganizes and stabilizes during learning. https://doi.org/10.1101/2020.07.08.193334

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