Venue: Centre Broca
Pauline Belujon
MCU
Laboratoire de Neurosciences Expérimentales et Cliniques (LNEC), Poitiers
https://lnec.labo.univ-poitiers.fr/membres/belujon-pauline/
Title
Insular Cortex and Dopamine System Dysregulation in the Addicted Brain
Abstract
Multiple lines of preclinical and clinical evidence have shown that prolonged exposure to drugs, followed by abstinence, induces lasting neuroadaptations across brain systems involved in affect regulation, interoception, stress response, and cognitive control. These changes are characterized by disruptions in dopamine signaling, particularly in the ventral tegmental area (VTA), where reduced dopaminergic activity impairs reward processing. Additionally, alterations in synaptic plasticity in regions such as the nucleus accumbens and prefrontal cortex impact motivation, emotion, and decision-making. Our research focuses on understanding how chronic drug exposure and subsequent abstinence affect both the activity of dopamine neurons and synaptic plasticity within key brain circuits. A major focus of our work is the insular cortex, a region critical for processing interoceptive and emotional information, and increasingly recognized for its involvement in addiction. We explore how the insular cortex influences the activity of dopaminergic neurons in the VTA, integrates inputs from other brain regions, and modulates behavior during abstinence, with a particular focus on how it contributes to the risk of relapse. By integrating electrophysiological techniques, behavioral models of relapse, and circuit-level analyses, we aim to uncover how dysregulation of the dopamine system, particularly within circuits involving the insular cortex, contributes to persistent vulnerability during abstinence. Ultimately, our research seeks to reveal how the insular cortex drives addiction-related brain changes and how this understanding can guide the development of targeted therapies for addiction recovery
Selected publications
Gauthier M., Hebert LP., Dugast E., Lardeux V., Letort K, Belnoue L, Balado E, Solinas M., Belujon P. (2025)
« Sex-dependent effects of stress on aIC-NAc circuit neuroplasticity: Role of the endocannabinoid system”
Prog Neuropsychopharmacol Biol Psychiatry Mar 18:138:111335
Salin A., Dugast E., Lardeux V., Solinas M., Belujon P. (2023)
“The amygdala-ventral pallidum pathway contributes to a hypodopaminergic state in the ventral tegmental area during protracted abstinence from chronic cocaine”
Br J Pharmacol. 2023 Jul;180(14):1819-1831.
Salin A., Lardeux V., Solinas M., Belujon P. (2021)
“Protracted abstinence from extended cocaine self-administration is associated with hypodopaminergic activity in the VTA but not in the SNc”
Int. J. Neuropsychopharmacol Jul 14;24(6):499-504
Nicolas C., Tauber C., Lepelletier F.X., Chalon S., Belujon P., Galineau L., Solinas M. (2017)
“Longitudinal changes in brain metabolic activity after withdrawal from escalation of cocaine self-administration”
Neuropsychopharmacology Sep;42(10):1981-1990
Belujon P., Jakobowski N.L., Dollish H.K. and Grace A.A. (2016)
“Withdrawal from acute amphetamine induces an amygdala-driven attenuation of dopamine neuron activity: reversal by ketamine”
Neuropsychopharmacology. Jan;41(2):619-27
Belujon P. and Grace A.A. (2014)
“Restoring balance in depression: ketamine reverses deficit in dopamine-dependent synaptic plasticity”
Biological Psychiatry, Dec 15;76(12):927-36