Long-term stability of cortical ensembles
- Columbia University, United States
Abstract
Neuronal ensembles, coactive groups of neurons found in spontaneous and evoked cortical activity, are causally related to memories and perception, but it still unknown how stable or flexible they are over time. We used two-photon multiplane calcium imaging to track over weeks the activity of the same pyramidal neurons in layer 2/3 of the visual cortex from awake mice and recorded their spontaneous and visually evoked responses. Less than half of the neurons were commonly active across any two imaging sessions. These 'common neurons' formed stable ensembles lasting weeks, but some ensembles were also transient and appeared only in one single session. Stable ensembles preserved ~68 % of their neurons up to 46 days, our longest imaged period, and these 'core' cells had stronger functional connectivity. Our results demonstrate that neuronal ensembles can last for weeks and could, in principle, serve as a substrate for long-lasting representation of perceptual states or memories.
Data availability
Data analyzed during this study are included in the manuscript and supporting files. Links to download the code developed in MATLAB are included in Methods. Data can also be found on Dryad, under the doi: 10.5061/dryad.cfxpnvx5m
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Long-term stability of cortical ensemblesDryad Digital Repository, doi:10.5061/dryad.cfxpnvx5m.
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A large-scale standardized physiological survey reveals functional organization of the mouse visual cortexAllen Brain Observatory Visual Coding.
Article and author information
Author details
Jesús Pérez-Ortega
Funding
National Eye Institute (R01EY011787)
- Rafael Yuste
National Institute of Mental Health (R01MH115900)
- Rafael Yuste
Consejo Nacional de Ciencia y Tecnología (CVU365863)
- Jesús Pérez-Ortega
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 experimental procedures were carried out in accordance with the US National Institutes of Health and Columbia University Institutional Animal Care and Use Committee (protocol AC-AAV3464).
Copyright
© 2021, Pérez-Ortega 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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