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bioRxiv · 10.1101/2021.03.22.436529

Noise Effect on the Temporal Patterns of Neural Synchrony

Abstract

Neural synchrony in the brain is often present in an intermittent fashion, i.e., there are intervals of synchronized activity interspersed with intervals of desynchronized activity. A series of experimental studies showed that this kind of temporal patterning of neural synchronization may be very specific and may be correlated with behavior (even if the average synchrony strength is not changed). Prior studies showed that a network with many short desynchronized intervals may be functionally different from a network with few long desynchronized intervals as it may be more sensitive to synchronizing input signals. In this study, we investigated the effect of channel noise on the temporal patterns of neural synchronization. We employed a small network of conductance-based model neurons that were mutually connected via excitatory synapses. The resulting dynamics of the network was studied using the same time-series analysis methods as used in prior experimental and computational studies. While it is well known that synchrony strength generally degrades with noise, we found that noise also affects the temporal patterning of synchrony. Noise, at a sufficient intensity (yet too weak to substantially affect synchrony strength), promotes dynamics with predominantly short (although potentially very numerous) desynchronizations. Thus, channel noise may be one of the mechanisms contributing to the short desynchronization dynamics observed in multiple experimental studies. HighlightsO_LIChannel noise alters the temporal pattern of intermittent neural synchrony C_LIO_LINoise may alter this pattern without significant change in average synchrony strength C_LIO_LIThe resulting patterning is similar to that observed in multiple experiments C_LI

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BibTeXRIS

Zirkle, J., Rubchinsky, L. L.. 2021-03-23. Noise Effect on the Temporal Patterns of Neural Synchrony. https://doi.org/10.1101/2021.03.22.436529

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