The impact of bilateral ongoing activity on evoked responses in mouse cortex
- University College London, United Kingdom
Abstract
In the absence of external stimuli or overt behavior, the activity of the left and right cortical hemispheres shows fluctuations that are largely bilateral. Here we show that these fluctuations are largely responsible for the variability observed in cortical responses to sensory stimuli. Using widefield imaging of voltage and calcium signals, we measured activity in the cortex of mice performing a visual detection task. Bilateral fluctuations invested all areas, particularly those closest to the midline. Activity was less bilateral in the monocular region of primary visual cortex and, especially during task engagement, in secondary motor cortex. Ongoing bilateral fluctuations dominated unilateral visual responses, and interacted additively with them, explaining much of the variance in trial-by-trial activity. Even though these fluctuations occurred in regions necessary for the task, they did not affect detection behavior. We conclude that bilateral ongoing activity continues during visual stimulation and has a powerful additive impact on visual responses.
Data availability
Data has been deposited to Dryad Digital Repository under the doi:10.5061/dryad.rd00gk7
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Data from: The impact of bilateral ongoing activity on evoked responses in mouse cortexDryad Digital Repository, 10.5061/dryad.rd00gk7.
Article and author information
Author details
Nicholas A Steinmetz
Funding
Wellcome (108726)
- Kenneth D Harris
- Matteo Carandini
Japan Society for the Promotion of Science
- Daisuke Shimaoka
Human Frontier Science Program (LT001071/2015-L)
- Nicholas A Steinmetz
Marie Skłodowska-Curie (656528)
- Nicholas A Steinmetz
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Experimental procedures were conducted according to the UK Animals ScientificProcedures Act (1986), under personal and project (70/8021) licenses released by the Home Office following appropriate ethics review.
Copyright
© 2019, Shimaoka 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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The impact of bilateral ongoing activity on evoked responses in mouse cortex
eLife 8:e43533.
https://doi.org/10.7554/eLife.43533
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