Mechanisms that allow cortical preparatory activity without inappropriate movement
We reveal a novel mechanism that explains how preparatory activity can evolve in motor-related cortical areas without prematurely inducing movement. The smooth eye movement region of the frontal eye fields (FEFSEM) is a critical node in the neural circuit controlling smooth pursuit eye movement. Preparatory activity evolves in the monkey FEFSEM during fixation in parallel with an objective measure of visual-motor gain. We propose that the use of FEFSEM output as a gain signal rather than a movement command allows for preparation to progress in pursuit without causing movement. We also show that preparatory modulation of firing rate in FEFSEM predicts movement, providing evidence against the 'movement-null' space hypothesis as an explanation of how preparatory activity can progress without movement. Finally, there is a partial reorganization of FEFSEM population activity between preparation and movement that would allow for a directionally non-specific component of preparatory visual-motor gain enhancement in pursuit.
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Article and author information
National Institutes of Health (R01-EY027373)
- Stephen G Lisberger
National Institutes of Health (F30-EY027684)
- Timothy R Darlington
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All procedures received prior approval by Duke's Institutional Animal Care and Use Committee (protocol A085-18-04) and were in compliance with the National Institutes of Health's Guide for the Care and Use of Laboratory Animals.
- Kunlin Wei, Peking University, China
- Received: August 8, 2019
- Accepted: February 20, 2020
- Accepted Manuscript published: February 21, 2020 (version 1)
- Version of Record published: March 6, 2020 (version 2)
© 2020, Darlington & Lisberger
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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