Inhibition is a prevalent mode of activity in the neocortex around awake hippocampal ripples in mice
Abstract
Coordinated peri-ripple activity in the hippocampal-neocortical network is essential for mnemonic information processing in the brain. Hippocampal ripples likely serve different functions in sleep and awake states. Thus, the corresponding neocortical activity patterns may differ in important ways. We addressed this possibility by conducting voltage and glutamate wide-field imaging of the neocortex with concurrent hippocampal electrophysiology in awake mice. Contrary to our previously published sleep results, deactivation and activation were dominant in post-ripple neocortical voltage and glutamate activity, respectively, especially in the agranular retrosplenial cortex (aRSC). Additionally, the spiking activity of aRSC neurons, estimated by two-photon calcium imaging, revealed the existence of two subpopulations of excitatory neurons with opposite peri-ripple modulation patterns: one increases and the other decreases firing rate. These differences in peri-ripple spatiotemporal patterns of neocortical activity in sleep versus awake states might underlie the reported differences in the function of sleep versus awake ripples.
Data availability
The data used to obtain the results of this article have been deposited on Dryad and can be reached via https://doi.org/10.5061/dryad.8kprr4xrk
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Data for: Inhibition is a prevalent mode of activity in the neocortex around awake hippocampal ripples in miceDryad Digital Repository, doi:10.5061/dryad.8kprr4xrk.
Article and author information
Author details
Funding
Natural Sciences and Engineering Research Council of Canada (40352)
- Majid H Mohajerani
Alberta Prion Research Institute (43568)
- Majid H Mohajerani
Canadian Institutes of Health Research (390930)
- Majid H Mohajerani
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Adrien Peyrache, McGill University, Canada
Ethics
Animal experimentation: The animal protocol (#2209) was approved by the University of Lethbridge Animal Care Committee and was in accordance with guidelines set forth by the Canadian Council for Animal Care.
Version history
- Preprint posted: March 4, 2022 (view preprint)
- Received: April 15, 2022
- Accepted: January 6, 2023
- Accepted Manuscript published: January 16, 2023 (version 1)
- Version of Record published: January 25, 2023 (version 2)
Copyright
© 2023, Karimi Abadchi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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