Mesolimbic dopamine projections mediate cue-motivated reward seeking but not reward retrieval in rats
- University of California, Irvine, United States
- University of California, Los Angeles, United States
Abstract
Efficient foraging requires an ability to coordinate discrete reward-seeking and reward-retrieval behaviors. We used pathway-specific chemogenetic inhibition to investigate how rats' mesolimbic and mesocortical dopamine circuits contribute to the expression and modulation of reward seeking and retrieval. Inhibiting ventral tegmental area dopamine neurons disrupted the tendency for reward-paired cues to motivate reward seeking, but spared their ability to increase attempts to retrieve reward. Similar effects were produced by inhibiting dopamine inputs to nucleus accumbens, but not medial prefrontal cortex. Inhibiting dopamine neurons spared the suppressive effect of reward devaluation on reward seeking, an assay of goal-directed behavior. Attempts to retrieve reward persisted after devaluation, indicating they were habitually performed as part of a fixed action sequence. Our findings show that complete bouts of reward seeking and retrieval are behaviorally and neurally dissociable from bouts of reward seeking without retrieval. This dichotomy may prove useful for uncovering mechanisms of maladaptive behavior.
Data availability
All data generated and analyzed during this study are included in supporting files. Source data files have been provided for Figures 1, 3, 4 and 5, as well as their respective supplemental figures.
Article and author information
Author details
Funding
National Institute of Mental Health (106972)
- Kate M Wassum
- Sean B Ostlund
National Institute of Diabetes and Digestive and Kidney Diseases (098709)
- Sean B Ostlund
National Institute on Drug Abuse (029035)
- Sean B Ostlund
National Institute on Aging (045380)
- Sean B Ostlund
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Naoshige Uchida, Harvard University, United States
Ethics
Animal experimentation: All experimental procedures that involved rats were approved by the UC Irvine Institutional Animal Care and Use Committee (protocol AUP-17-68) and were in accordance with the National Research Council Guide for the Care and Use of Laboratory Animals.
Version history
- Received: November 10, 2018
- Accepted: May 19, 2019
- Accepted Manuscript published: May 20, 2019 (version 1)
- Version of Record published: June 4, 2019 (version 2)
Copyright
© 2019, Halbout 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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Mesolimbic dopamine projections mediate cue-motivated reward seeking but not reward retrieval in rats
eLife 8:e43551.
https://doi.org/10.7554/eLife.43551
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