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bioRxiv · 10.1101/2021.06.11.448131

OFF-periods reduce the complexity of neocortical activity during sleep

Gonzalez, J.·Cavelli, M.·Tort, A. B.·Torterolo, P.·Rubido, N.
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Abstract

Complexity of electroencephalographic signals decreases during slow-wave sleep (SWS), however, the neural mechanism for this decrease remains elusive. Here, we show that this complexity reduction is caused by synchronous neuronal OFF-periods. We analyse in-vivo recordings from neocortical neuronal populations, finding that OFF-periods in SWS trap cortical dynamics, making the population activity more recurrent, deterministic, and less chaotic than during REM sleep or Wakefulness. Importantly, when we exclude OFF-periods, SWS becomes indistinguishable from Wakefulness or REM sleep. In fact, we show that spiking activity for all states has a universal scaling compatible with critical phenomena. We complement these results by a critical branching model that replicates our experimental findings, where we show that forcing OFF-periods to a percentage of neurons suffices to generate a decrease in complexity that replicates SWS.

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Gonzalez, J., Cavelli, M., Tort, A. B., Torterolo, P., Rubido, N.. 2021-06-13. OFF-periods reduce the complexity of neocortical activity during sleep. https://doi.org/10.1101/2021.06.11.448131

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