UP-DOWN cortical dynamics reflect state transitions in a bistable network
Abstract
In the idling brain, neuronal circuits transition between periods of sustained firing (UP state) and quiescence (DOWN state), a pattern the mechanisms of which remain unclear. Here we analyzed spontaneous cortical population activity from anesthetized rats and found that UP and DOWN durations were highly variable and that population rates showed no significant decay during UP periods. We built a network rate model with excitatory (E) and inhibitory (I) populations exhibiting a novel bistable regime between a quiescent and an inhibition-stabilized state of arbitrarily low rate. Fluctuations triggered state transitions, while adaptation in E cells paradoxically caused a marginal decay of E-rate but a marked decay of I-rate in UP periods, a prediction that we validated experimentally. A spiking network implementation further predicted that DOWN-to-UP transitions must be caused by synchronous high-amplitude events. Our findings provide evidence of bistable cortical network that exhibits non-rhythmic state transitions when the brain rests.
Article and author information
Author details
Funding
AGAUR of the Generalitat de Catalunya (SGR14-1265)
- Albert Compte
Spanish Ministry of Economy and Competitiveness together with the European Regional Development Fund (BFU2009-09537,BFU2012-34838)
- Albert Compte
Spanish Ministry of Economy and Competitiveness together with the European Regional Development Fund (RYC-2011-08755)
- Alex Roxin
EU Biotrack contract (PCOFUND-GA-2008-229673)
- Alex Roxin
Hungarian Brain Research Program Grant (KTIA_NAP_13-2-2014-0016)
- Peter Barthó
Spanish Ministry of Economy and Competitiveness together with the European Regional Development Fund (SAF2010-15730,SAF2013-46717-R,RYC-2009-04829)
- Jaime de la Rocha
EU Marie Curie grants (PIRG07-GA-2010-268382)
- Jaime de la Rocha
Spanish Ministry of Economy and Competitiveness (SAF2015-70324R)
- Jaime de la Rocha
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study involved analysis of previously published and new data. Previously published data (Bartho et al, J Neurophys. 2004, 92(1)) was obtained under a protocol approved by the Rutgers University Animal Care and Use Committee. One new data set was acquired in accordance with a protocol approved by the Animal Welfare Committee at University of Lethbridge (protocol # 0907). All surgeries were performed under anesthesia, and every effort was made to minimize suffering.
Copyright
© 2017, Jercog 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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