Attention stabilizes the shared gain of V4 populations
Abstract
Responses of sensory neurons represent stimulus information, but are also influenced by internal state. For example, when monkeys direct their attention to a visual stimulus, the response gain of specific subsets of neurons in visual cortex changes. Here, we develop a functional model of population activity to investigate the structure of this effect. We fit the model to the spiking activity of bilateral neural populations in area V4, recorded while the animal performed a stimulus discrimination task under spatial attention. The model reveals four separate time-varying shared modulatory signals, the dominant two of which each target task-relevant neurons in one hemisphere. In attention-directed conditions, the associated shared modulatory signal decreases in variance. This finding provides an interpretable and parsimonious explanation for previous observations that attention reduces variability and noise correlations of sensory neurons. Finally, the recovered modulatory signals reflect previous reward, and are predictive of choice behavior.
Article and author information
Author details
Reviewing Editor
- Matteo Carandini, University College London, United Kingdom
Version history
- Received: May 26, 2015
- Accepted: November 1, 2015
- Accepted Manuscript published: November 2, 2015 (version 1)
- Accepted Manuscript updated: December 24, 2015 (version 2)
- Version of Record published: February 5, 2016 (version 3)
Copyright
© 2015, Rabinowitz 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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