Characterization of Nucleus Accumbens Dopamine Dynamics during Positive and Negative Operant Reinforcement in Rats
Abstract
We previously reported, using in vivo fiber photometry, that operant responding reinforced by access to a peer (social self-administration) is associated with phasic dopamine increases in nucleus accumbens (NAc) core following lever insertion (reward-availability cue) and gradual increases preceding lever-pressing. Here, we sought to replicate these findings and determine whether dopamine signals (1) generalize to responding for high-carbohydrate palatable food, (2) show opposite patterns during negative reinforcement (shock avoidance/escape), and (3) depend on whether reinforcers are experienced alone or together. We trained male and female rats to lever-press for access to a same-sex peer (15 s/trial) and palatable food (45 mg pellet/trial), followed by shock avoidance/escape (0.18–0.28 mA). After training, we expressed the dopamine sensor GRAB-DA2m and implanted optic fibers into NAc core. We measured dopamine activity during sessions with either one or three reinforcers. During social self-administration, dopamine activity showed phasic increases following lever insertion and gradual increases preceding lever-pressing; responses were moderately greater during sessions with all three reinforcers. Palatable food self-administration showed a similar pattern, but responses were approximately twofold greater during single-reinforcer sessions. During shock avoidance/escape, dopamine activity showed phasic decreases at warning onset, lever insertion, and shock onset; responses were also greater during single-reinforcer sessions. Results suggest that NAc core dopamine signaling distinguishes positive from negative reinforcement and is modulated by reinforcer availability. Compared with single-reinforcer sessions, dopamine responses during food self-administration and shock avoidance/escape were reduced during sessions with all three reinforcers, whereas responses during social self-administration modestly increased.
Related
- Divergent Dopamine Dynamics within the Accumbens Core
- From Reward to Cue: Developmental Changes in Nucleus Accumbens and Dopamine Signaling from Adolescence to Adulthood
- Long-term sugar consumption alters extracellular dopamine and acetylcholine levels in the nucleus accumbens shell
- Dopamine signaling in the medial accumbens shell constrains the duration of reinforced actions
- Acute partner loss enhances social motivation and nucleus accumbens dopamine release in prairie voles
BibTeX
@article{chow2026characterization,
title = {{Characterization of Nucleus Accumbens Dopamine Dynamics during Positive and Negative Operant Reinforcement in Rats}},
author = {Jonathan J. Chow and Emma M. Pilz and Huiling Wang and Kauê M. Costa and Geoffrey Schoenbaum and Yavin Shaham},
journal = {eneuro},
year = {2026},
month = oct,
doi = {10.1523/eneuro.0235-26.2026},
url = {https://www.eneuro.org/lookup/doi/10.1523/ENEURO.0235-26.2026},
note = {CC BY-NC-SA 4.0},
}
RIS
TY - JOUR
TI - Characterization of Nucleus Accumbens Dopamine Dynamics during Positive and Negative Operant Reinforcement in Rats
AU - Jonathan J. Chow
AU - Emma M. Pilz
AU - Huiling Wang
AU - Kauê M. Costa
AU - Geoffrey Schoenbaum
AU - Yavin Shaham
PY - 2026
DA - 2026/10/13
JO - eneuro
DO - 10.1523/eneuro.0235-26.2026
UR - https://www.eneuro.org/lookup/doi/10.1523/ENEURO.0235-26.2026
AB - We previously reported, using in vivo fiber photometry, that operant responding reinforced by access to a peer (social self-administration) is associated with phasic dopamine increases in nucleus accumbens (NAc) core following lever insertion (reward-availability cue) and gradual increases preceding lever-pressing. Here, we sought to replicate these findings and determine whether dopamine signals (1) generalize to responding for high-carbohydrate palatable food, (2) show opposite patterns during negative reinforcement (shock avoidance/escape), and (3) depend on whether reinforcers are experienced alone or together. We trained male and female rats to lever-press for access to a same-sex peer (15 s/trial) and palatable food (45 mg pellet/trial), followed by shock avoidance/escape (0.18–0.28 mA). After training, we expressed the dopamine sensor GRAB-DA2m and implanted optic fibers into NAc core. We measured dopamine activity during sessions with either one or three reinforcers. During social self-administration, dopamine activity showed phasic increases following lever insertion and gradual increases preceding lever-pressing; responses were moderately greater during sessions with all three reinforcers. Palatable food self-administration showed a similar pattern, but responses were approximately twofold greater during single-reinforcer sessions. During shock avoidance/escape, dopamine activity showed phasic decreases at warning onset, lever insertion, and shock onset; responses were also greater during single-reinforcer sessions. Results suggest that NAc core dopamine signaling distinguishes positive from negative reinforcement and is modulated by reinforcer availability. Compared with single-reinforcer sessions, dopamine responses during food self-administration and shock avoidance/escape were reduced during sessions with all three reinforcers, whereas responses during social self-administration modestly increased.
SN - 2373-2822
ER -