Differential coding of positive and negative reinforcement signals across the dopaminergic system

January 30, 2025 @ 11:00 am to 12:00 pm

Vicent Breton-Provencher, Cervo Brain Research Center

117 Henderson Building
University Park

Abstract:
The dopaminergic system facilitates associative learning and motivation by signaling reward expectation and positive or negative valence in selected brain regions. Previous studies measuring somatic and axonal activity suggest a heterogeneous representation of reinforcement signaling by dopaminergic neurons, but it remains unclear how dopamine signals for expectation and valence interact in various brain regions. Here, we used an improved fluorescent dopamine sensor to record dopamine signals associated with reward predictions and valence in eight distinct striatal and non-striatal regions. We found homogeneous signaling of unexpected rewards and reward-predicting cues across the dopaminergic system. In contrast, reward omission following reward-predicting cues and aversive stimuli both produced heterogeneous signaling of dopamine. By using dimensionality reduction to examine the main axis of covariance of dopamine release across the brain, we found that reward prediction error signals are encoded by similar manifolds, whereas aversive stimulus signals are encoded by orthogonal manifolds. This suggests a high level of covariance during reward prediction error signaling that is not conserved during aversive stimulus responses. Together, our results provide evidence of contrasting reinforcement signals across the primary targets of dopaminergic pathways through which dopamine release supports learning and motivation. In the last part of the talk, I will also discuss recent results from our lab that have studied the circuits controlling noradrenergic release and the function of this release during learned behavior.

About the Speaker:
Dr. Vincent Breton-Provencher is an Assistant Professor in Psychiatry and Neuroscience at Université Laval and a researcher at the CERVO Brain Research Centre in Québec City, Canada. He earned his Ph.D. in Neurobiology at Université Laval, where he studied the integration and function of adult-born neurons in the olfactory bulb. He later completed postdoctoral training at MIT's Picower Institute for Learning and Memory under Dr. Mriganka Sur. His research explores the dynamics of the noradrenergic and dopaminergic systems, particularly their role in arousal states, learned behaviors, and neuroplasticity.

Key publications:
- Tanguay, E., Bouchard, S.J., Lévesque, M., De Koninck, P., Breton-Provencher, V. Shining light on the noradrenergic system. Neurophotonics. 2023
- Breton-Provencher, V., Drummond, G.T., Feng, J., Li, Y., & Sur, M. Spatiotemporal dynamics of noradrenaline during learned behaviour. Nature. 2022
- Breton-Provencher, V., Sur, M. Active control of arousal by a locus coeruleus GABAergic circuit. Nat. Neuroscience 2019

Contact

Grayson Sipe
gsipe@psu.edu