Robust effects of corticothalamic feedback and behavioral state on movie responses in mouse dLGN
Abstract
Neurons in the dorsolateral geniculate nucleus (dLGN) of the thalamus receive a substantial proportion of modulatory inputs from corticothalamic (CT) feedback and brain stem nuclei. Hypothesizing that these modulatory influences might be differentially engaged depending on the visual stimulus and behavioral state, we performed in vivo extracellular recordings from mouse dLGN while optogenetically suppressing CT feedback and monitoring behavioral state by locomotion and pupil dilation. For naturalistic movie clips, we found CT feedback to consistently increase dLGN response gain and promote tonic firing. In contrast, for gratings, CT feedback effects on firing rates were mixed. For both stimulus types, the neural signatures of CT feedback closely resembled those of behavioral state, yet effects of behavioral state on responses to movies persisted even when CT feedback was suppressed. We conclude that CT feedback modulates visual information on its way to cortex in a stimulus-dependent manner, but largely independently of behavioral state.
Data availability
Data and source code used to generate the figures in the manuscript has been made available on Dryad (https://doi.org/10.5061/dryad.xgxd254j7).
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Robust effects of corticothalamic feedback and behavioral state on movie responses in mouse dLGNDryad Digital Repository, doi:10.5061/dryad.xgxd254j7.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (Robust Vision: Inference Principles and Neural Mechanisms,TP 13,project number: 276693517)
- Laura Busse
Deutsche Forschungsgemeinschaft (SFB 870 TP 19,project number 118803580)
- Laura Busse
Deutsche Forschungsgemeinschaft (DFG BU 1808/5-1)
- Laura Busse
Joachim Herz Stiftung (add-on fellowship)
- Gregory Born
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 complied with the European Communities Council Directive 2010/63/ECand the German Law for Protection of Animals, and were approved by local authorities,following appropriate ethics review.
Copyright
© 2022, Spacek 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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