Learning speed and detection sensitivity controlled by distinct cortico-fugal neurons in visual cortex
Vertebrates can change their behavior upon detection of visual stimuli according to the outcome their actions produce. Such goal-directed behavior involves evolutionary conserved brain structures like the striatum and optic tectum, which receive ascending visual input from the periphery. In mammals, however, these structures also receive descending visual input from visual cortex (VC), via neurons that give rise to cortico-fugal projections. The function of cortico-fugal neurons in visually-guided, goal-directed behavior remains unclear. Here we address the impact of two populations of cortico-fugal neurons in mouse VC in the learning and performance of a visual detection task. We show that the ablation of striatal projecting neurons reduces learning speed while the ablation of superior colliculus projecting neurons does not impact learning but reduces detection sensitivity. This functional dissociation between distinct cortico-fugal neurons in controlling learning speed and detection sensitivity suggests an adaptive contribution of cortico-fugal pathways even in simple goal-directed behavior.
All data generated or analyzed during this study are included in the manuscript and supporting files. Numerical data for graphs represented in figures 1-6, figure 1-figure supplement 2,3,4,5, figure 2-figure supplement 1, figure 4-figure supplement 1 are provided as source data files. The software used to generate visual stimuli and record neuronal activity is available at: https://github.com/mscaudill/neuroGit and https://github.com/aresulaj/ResRueOlsSca18.
Article and author information
National Eye Institute (NIH R01EY025668)
- Massimo Scanziani
Howard Hughes Medical Institute
- Massimo Scanziani
European Molecular Biology Organization (ALTF741-2012)
- Sarah Ruediger
Swiss National Science Foundation (151168)
- Sarah Ruediger
Swiss National Science Foundation (138719)
- Sarah Ruediger
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All experimental procedures were performed with the approval of the Committee on Animal Care at UCSD and UCSF. Authorization # AN179056
- Inna Slutsky, Tel Aviv University, Israel
- Received: May 23, 2020
- Accepted: December 6, 2020
- Accepted Manuscript published: December 7, 2020 (version 1)
- Version of Record published: December 18, 2020 (version 2)
© 2020, Ruediger & Scanziani
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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