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bioRxiv · 10.1101/766873

Mechanisms that allow cortical preparatory activity without inappropriate movement

Darlington, T. R.·Lisberger, S. G.
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Abstract

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 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 allows for preparation to progress in the pursuit system without causing movement. We also show that preparatory modulation of firing rate in FEFSEM progresses in a way that predicts movement, providing evidence against the \"movement-null\" space hypothesis of how preparatory activity can progress without movement. Finally, there is partial reorganization of FEFSEM population activity between preparation and movement. We propose that this reorganization allows for a directionally non-specific component of preparatory visual-motor gain enhancement in the pursuit system.

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Darlington, T. R., Lisberger, S. G.. 2019-09-12. Mechanisms that allow cortical preparatory activity without inappropriate movement. https://doi.org/10.1101/766873

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