Mechanisms underlying the response of mouse cortical networks to optogenetic manipulation
Abstract
GABAergic Interneurons can be subdivided into three subclasses: parvalbumin positive (PV), somatostatin positive (SOM) and serotonin positive neurons. With principal cells (PCs) they form complex networks. We examine PCs and PV responses in mouse anterior lateral motor cortex (ALM) and barrel cortex (S1) upon PV photostimulation in vivo. In ALM layer 5 and S1, the PV response is paradoxical: photoexcitation reduces their activity. This is not the case in ALM layer 2/3. We combine analytical calculations and numerical simulations to investigate how these results constrain the architecture. Two-population models cannot explain the results. Four-population networks with V1-like architecture account for the data in ALM layer 2/3 and layer 5. Our data in S1 can be explained if SOM neurons receive inputs only from PCs and PV neurons. In both four-population models, the paradoxical effect implies not too strong recurrent excitation. It is not evidence for stabilization by inhibition.
Data availability
Electrophysiology data and code used are available at Github (https://github.com/Amahrach/Paper4pop).
Article and author information
Author details
Funding
Agence Nationale de la Recherche (14-NEUC-0001-01)
- Carl van Vreeswijk
Agence Nationale de la Recherche (13-BSV4-0014-02)
- David Hansel
Agence Nationale de la Recherche (09-SYSC-002-01)
- David Hansel
Helen Hay Whitney Foundation
- Nuo Li
Robert and Janice McNair Foundation
- Nuo Li
Alfred P. Sloan Foundation
- Nuo Li
National Institutes of Health (NS104781)
- Nuo Li
Pew Charitable Trusts
- Nuo Li
Simons Collaboration on the Global Brain (543005)
- Nuo Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All procedures were in accordance with protocols approved by the Janelia Research Campus and Baylor College of Medicine Institutional Animal Care and Use Committee.
Copyright
© 2020, Mahrach 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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