Cortex commands the performance of skilled movement
- Janelia Farm Research Campus, Howard Hughes Medical Institute, United States
Abstract
Mammalian cerebral cortex is accepted as being critical for voluntary motor control, but what functions depend on cortex is still unclear. Here we used rapid, reversible optogenetic inhibition to test the role of cortex during a head-fixed task in which mice reach, grab, and eat a food pellet. Sudden cortical inhibition blocked initiation or froze execution of this skilled prehension behavior, but left untrained forelimb movements unaffected. Unexpectedly, kinematically normal prehension occurred immediately after cortical inhibition even during rest periods lacking cue and pellet. This 'rebound' prehension was only evoked in trained and food-deprived animals, suggesting that a motivation-gated motor engram sufficient to evoke prehension is activated at inhibition's end. These results demonstrate the necessity and sufficiency of cortical activity for enacting a learned skill.
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Animal experimentation: Animal procedures were performed in accordance with protocols (13-99) approved by the Institutional Animal Care and Use Committee (IACUC) of the Janelia Research Campus.
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© 2015, Guo 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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Cortex commands the performance of skilled movement
eLife 4:e10774.
https://doi.org/10.7554/eLife.10774
Further reading
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