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bioRxiv · 10.1101/2021.05.14.444189

Intraneuronal chloride levels encode tiredness in cortex

Alfonsa, H.·Brodersen, P.·Newey, S.·Yamagata, T.·Panayi, M. C.·Bannerman, D.·Vyazovskiy, V. V.·Akerman, C.
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Abstract

Continuous periods of wakefulness are associated with reduced performance levels due to the build-up of sleep pressure in active regions of the brain. These effects manifest as use-dependent changes in cortical network activity and the mechanisms underlying these changes represent targets for overcoming the cognitive effects of tiredness. Here we reveal a central role for intraneuronal chloride levels, which increase in a use-dependent manner during waking, and reduce the strength of local synaptic inhibition in mouse cortex. Activity-dependent increases in chloride account for spatial and temporal features of sleep pressure, they underlie cortical network oscillations in the sleep-deprived state, and targeting chloride regulation in cortex can rescue performance levels when tired. These findings provide a missing link between sleep-wake history, synaptic transmission and cortical dynamics. One-Sentence SummaryThe effects of sleep pressure on cortical function are caused by use-dependent changes in chloride-mediated synaptic inhibition.

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Alfonsa, H., Brodersen, P., Newey, S., Yamagata, T., Panayi, M. C., Bannerman, D., Vyazovskiy, V. V., Akerman, C.. 2021-05-17. Intraneuronal chloride levels encode tiredness in cortex. https://doi.org/10.1101/2021.05.14.444189

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