Stable and dynamic representations of value in the prefrontal cortex
Abstract
Optimal decision-making requires that stimulus-value associations are kept up to date by constantly comparing the expected value of a stimulus with its experienced outcome. To do this, value information must be held in mind when a stimulus and outcome are separated in time. However, little is known about the neural mechanisms of working memory (WM) for value. Contradicting theories have suggested WM requires either persistent or transient neuronal activity, with stable or dynamic representations respectively. To test these hypotheses, we recorded neuronal activity in the orbitofrontal and anterior cingulate cortex of two monkeys performing a valuation task. We found that features of all hypotheses were simultaneously present in prefrontal activity, and no single hypothesis was exclusively supported. Instead, mixed dynamics supported robust, time invariant value representations while also encoding the information in a temporally specific manner. We suggest that this hybrid coding is a critical mechanism supporting flexible cognitive abilities.
Data availability
The neural recording data analyzed in this paper is available online at https://doi.org/10.5061/dryad.4j0zpc88b
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Single- and multi-unit firing rate of two macaque monkeys' OFC and ACC neurons in value based decision-making taskDryad Digital Repository, doi:10.5061/dryad.4j0zpc88b.
Article and author information
Author details
Funding
National Institute of Mental Health (R01-MH121448)
- Joni D Wallis
National Institute of Mental Health (R01-MH097990)
- Joni D Wallis
Hilda and Preston Davis Foundation (Postdoctoral fellowship)
- Erin L Rich
National Institute on Drug Abuse (K08-DA039051)
- Erin L Rich
National Institute of Mental Health (R01-MH117763)
- Joni D Wallis
Whitehall Foundation Research Grant (Postdoctoral fellowship)
- Erin L Rich
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Geoffrey Schoenbaum, National Institute on Drug Abuse, National Institutes of Health, United States
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health (Assurance Number A3084-01). All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (Protocol Number R283) of the University of California at Berkeley. All surgery was performed under isoflurane anesthesia, and every effort was made to minimize suffering.
Version history
- Received: December 10, 2019
- Accepted: July 6, 2020
- Accepted Manuscript published: July 6, 2020 (version 1)
- Accepted Manuscript updated: July 8, 2020 (version 2)
- Version of Record published: July 29, 2020 (version 3)
Copyright
© 2020, Enel 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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