Uncovering circuit mechanisms of current sinks and sources with biophysical simulations of primary visual cortex
- University of Oslo, Norway
- Allen Institute for Brain Science, United States
- Allen Institute, United States
- Norwegian University of Life Sciences, Norway
Abstract
Local field potential (LFP) recordings reflect the dynamics of the current source density (CSD) in brain tissue. The synaptic, cellular and circuit contributions to current sinks and sources are ill-understood. We investigated these in mouse primary visual cortex using public Neuropixels recordings and a detailed circuit model based on simulating the Hodgkin-Huxley dynamics of >50,000 neurons belonging to 17 cell types. The model simultaneously captured spiking and CSD responses and demonstrated a two-way dissociation: Firing rates are altered with minor effects on the CSD pattern by adjusting synaptic weights, and CSD is altered with minor effects on firing rates by adjusting synaptic placement on the dendrites. We describe how thalamocortical inputs and recurrent connections sculpt specific sinks and sources early in the visual response, whereas cortical feedback crucially alters them in later stages. These results establish quantitative links between macroscopic brain measurements (LFP/CSD) and microscopic biophysics-based understanding of neuron dynamics and show that CSD analysis provides powerful constraints for modeling beyond those from considering spikes.
Data availability
The files necessary to run simulations of the different model versions presented in the paper as well as data resulting from simulations of those model versions are publicly available in Dryad: https://doi.org/10.5061/dryad.k3j9kd5b8The experimental data set utilized is publicly available at: https://portal.brain-map.org/explore/circuits/visual-coding-neuropixelsThe code generated for data analysis and producing the figures in this manuscript is publicly available at: https://github.com/atleer/CINPLA_Allen_V1_analysis.git.
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Uncovering circuit mechanisms of current sinks and sources with biophysical simulations of primary visual cortexDryad Digital Repository, doi:10.5061/dryad.k3j9kd5b8.
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20191003_AIBS_mouse_ecephys_brain_observatory_1_1DANDI Archive 000021.
Article and author information
Author details
Alexander J Stasik
Funding
Simula School of Research
- Atle E Rimehaug
European Union Horizon 2020 Research and Innovation program (785907)
- Espen Hagen
European Union Horizon 2020 Research and Innovation program (945539)
- Espen Hagen
Research Council of Norway (COBRA - project number 250128)
- Alexander J Stasik
IKTPLUSS-IKT and Digital Innovation (300504)
- Alexander J Stasik
National Institute of Neurological Disorders and Stroke (R01NS122742)
- Yazan N Billeh
- Josh H Siegle
- Kael Dai
- Shawn R Olsen
- Christof Koch
- Anton Arkhipov
National Institute of Biomedical Imaging and Bioengineering (R01EB029813)
- Yazan N Billeh
- Josh H Siegle
- Kael Dai
- Shawn R Olsen
- Christof Koch
- Anton Arkhipov
Allen Institute
- Yazan N Billeh
- Josh H Siegle
- Kael Dai
- Shawn R Olsen
- Christof Koch
- Anton Arkhipov
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Rimehaug 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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Uncovering circuit mechanisms of current sinks and sources with biophysical simulations of primary visual cortex
eLife 12:e87169.
https://doi.org/10.7554/eLife.87169
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