Opposite initialization to novel cues in dopamine signaling in ventral and posterior striatum in mice
Abstract
Dopamine neurons are thought to encode novelty in addition to reward prediction error (the discrepancy between actual and predicted values). In this study, we compared dopamine activity across the striatum using fiber fluorometry in mice. During classical conditioning, we observed opposite dynamics in dopamine axon signals in the ventral striatum ('VS dopamine') and the posterior tail of the striatum ('TS dopamine'). TS dopamine showed strong excitation to novel cues, whereas VS dopamine showed no responses to novel cues until they had been paired with reward. TS dopamine cue responses decreased over time, depending on what the cue predicted. Additionally, TS dopamine showed excitation to several types of stimuli including rewarding, aversive, and neutral stimuli whereas VS dopamine showed excitation only to reward or reward-predicting cues. Together, these results demonstrate that dopamine novelty signals are localized in TS along with general salience signals, while VS dopamine reliably encodes reward prediction error.
Article and author information
Author details
Funding
National Institute of Mental Health (R01MH095953)
- Naoshige Uchida
Harvard Mind Brain and Behavior
- Naoshige Uchida
National Institute of Mental Health (R01MH101207)
- Naoshige Uchida
National Institute of Mental Health (R01MH110404)
- Naoshige Uchida
Foundation pour la Recherche Medicale (SPE20150331860)
- Benedicte M Babayan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: 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. All of the animals were handled according to approved Harvard animal care and use committee (IACUC) protocols (#26-03) of Harvard University. All surgery was performed under isofluorane anesthesia, and every effort was made to minimize suffering.
Reviewing Editor
- Gary L Westbrook, Vollum Institute, United States
Publication history
- Received: September 27, 2016
- Accepted: January 4, 2017
- Accepted Manuscript published: January 5, 2017 (version 1)
- Version of Record published: January 27, 2017 (version 2)
Copyright
© 2017, Menegas 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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