Interhemispherically dynamic representation of an eye movement-related activity in mouse frontal cortex
Abstract
Cortical plasticity is fundamental to motor recovery following cortical perturbation. However, it is still unclear how this plasticity is induced at a functional circuit level. Here, we investigated motor recovery and underlying neural plasticity upon optogenetic suppression of a cortical area for eye movement. Using a visually-guided eye movement task in mice, we suppressed a portion of the secondary motor cortex (MOs) that encodes contraversive eye movement. Optogenetic unilateral suppression severely impaired contraversive movement on the first day. However, on subsequent days the suppression became inefficient and capability for the movement was restored. Longitudinal two-photon calcium imaging revealed that the regained capability was accompanied by an increased number of neurons encoding for ipsiversive movement in the unsuppressed contralateral MOs. Additional suppression of the contralateral MOs impaired the recovered movement again, indicating a compensatory mechanism. Our findings demonstrate that repeated optogenetic suppression leads to functional recovery mediated by the contralateral hemisphere.
Data availability
The source data are included in the manuscript and supporting files.
Article and author information
Author details
Funding
Japan Science and Technology Agency (PRESTO)
- Takashi R Sato
Deutsche Forschungsgemeinschaft (SA 2575/2-1)
- Takashi R Sato
Japan Science and Technology Agency (PRESTO)
- Tatsuo K Sato
Deutsche Forschungsgemeinschaft (SA 2575/3-1)
- Takashi R Sato
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Naoshige Uchida, Harvard University, United States
Ethics
Animal experimentation: All experimental procedures were approved by the University of Tuebingen (IN4/11) Medical University of South Carolina (IACUC-2018-00352), and National Center of Neurology and Psychiatry (2014005).
Version history
- Received: August 5, 2019
- Accepted: November 4, 2019
- Accepted Manuscript published: November 5, 2019 (version 1)
- Version of Record published: December 4, 2019 (version 2)
Copyright
© 2019, Sato 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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