Risk of punishment influences discrete and coordinated encoding of reward-guided actions by prefrontal cortex and VTA neurons
Abstract
Actions motivated by rewards are often associated with risk of punishment. Little is known about the neural representation of punishment risk during reward-seeking behavior. We modeled this circumstance in rats by designing a task where actions were consistently rewarded but probabilistically punished. Spike activity and local field potentials were recorded during task performance simultaneously from VTA and mPFC, two reciprocally connected regions implicated in reward-seeking and aversive behaviors. At the single unit level, we found that ensembles of putative dopamine and non-dopamine VTA neurons and mPFC neurons encode the relationship between action and punishment. At the network level, we found that coherent theta oscillations synchronize VTA and mPFC in a bottom-up direction, effectively phase-modulating the neuronal spike activity in the two regions during punishment-free actions. This synchrony declined as a function of punishment probability, suggesting that during reward-seeking actions, risk of punishment diminishes VTA-driven neural synchrony between the two regions.
Article and author information
Author details
Funding
National Institute of Mental Health (R56MH084906)
- Bita Moghaddam
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, NIDA Intramural Research Program, United States
Ethics
Animal experimentation: All surgical and experimental procedures were in strict accordance with the National Institute of Health's Guide to the Care and Use of Laboratory Animals, and were approved by the University of Pittsburgh Institutional Animal Care and Use Committee (Protocol #: 15065884).
Version history
- Received: June 30, 2017
- Accepted: October 22, 2017
- Accepted Manuscript published: October 23, 2017 (version 1)
- Version of Record published: November 21, 2017 (version 2)
Copyright
© 2017, Park & Moghaddam
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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