Dopamine encodes real-time reward availability and transitions between reward availability states on different timescales

• Authors: Abigail Kalmbach, New York State Psychiatric Institute; Vanessa Winiger, New York State Psychiatric Institute; Nuri Jeong, Emory University; Arun Asok, Columbia University; Charles R Gallistel, Rutgers University; Peter D Balsam, New York State Psychiatric Institute; Eleanor H Simpson, New York State Psychiatric Institute
• Journal Title: Nature Communications
• Volume: Volume 13
• Publisher: Nature Research (part of Springer Nature) | 2022-07-01
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1038/s41467-022-31377-2
• Subjects: Health Sciences, Mental Health; Engineering, Biomedical
• Keywords: Operant learning; Reward

Abstract

Optimal behavior requires interpreting environmental cues that indicate when to perform actions. Dopamine is important for learning about reward-predicting events, but its role in adapting to inhibitory cues is unclear. Here we show that when mice can earn rewards in the absence but not presence of an auditory cue, dopamine level in the ventral striatum accurately reflects reward availability in real-time over a sustained period (80 s). In addition, unpredictable transitions between different states of reward availability are accompanied by rapid (~1–2 s) dopamine transients that deflect negatively at the onset and positively at the offset of the cue. This Dopamine encoding of reward availability and transitions between reward availability states is not dependent on reward or activity evoked dopamine release, appears before mice learn the task and is sensitive to motivational state. Our findings are consistent across different techniques including electrochemical recordings and fiber photometry with genetically encoded optical sensors for calcium and dopamine.