Research interests

Using information acquired from peers is a strategy for many species to select the best option when deciding which food to eat. In mice, exposure to a demonstrator mouse that has eaten scented food drives a preference for that food over a differently scented alternative. Initial studies have shown that STFP depends on the observer mouse detecting olfactory cues in the breath of the demonstrator mouse during their interaction. Pharmacological studies have implicated the medial prefrontal cortex (mPFC) in social interaction and action-outcome evaluation. However, the brain circuits that govern food choice in a social context remain elusive. Here, we identify the piriform cortex (Pir) inputs to nucleus-accumbens (NAc)-projecting mPFC neurons as a substrate for STFP. Our experiments confirm that social learning can counterbalance innate food preference, an effect that was abolished when mPFC NAc-projectors neurons were chemogenetically silenced during the food choice session. Quantification of activity-dependent gene expression and slice electrophysiology in a pathway and behavior specific manner (FosCre mice) revealed an increase engagement of mPFC NAc-projectors during food choice when social learning occurred. By using a combination of state-of-the-art viral genetic tools for neuronanatomical tracing (TRIO method), we identified a prominent connection from the Pir to mPFC NAc-projectors. Ex vivo whole-cell recordings showed that social learning increases the excitation-to-inhibition balance in Pir to mPFC NAc-projectors connection. Ongoing experiments aim at testing the necessity of Pir to mPFC NAc-projectors circuit for STFP expression as well as probing the implication of other afferences such as the ventral hippocampus. Altogether, our results hold promise for a better understanding of the neurobiological mechanisms underlying food preference under social learning influence.

Selected publications

1: Loureiro M, Achargui R, Flakowski J, Van Zessen R, Stefanelli T, Pascoli V, Lüscher C. Social transmission of food safety depends on synaptic plasticity in the prefrontal cortex. Science. 2019 Jun 7;364(6444):991-995.
2: Loureiro M, Kramar C, Renard J, Rosen LG, Laviolette SR. Cannabinoid Transmission in the Hippocampus Activates Nucleus Accumbens Neurons and Modulates Reward and Aversion-Related Emotional Salience. Biol Psychiatry. 2016 Aug 1;80(3):216-25.

3: Norris C, Loureiro M, Kramar C, Zunder J, Renard J, Rushlow W, Laviolette SR. Cannabidiol Modulates Fear Memory Formation Through Interactions with Serotonergic Transmission in the Mesolimbic System. Neuropsychopharmacology. 2016 Nov;41(12):2839-2850.

4: Loureiro M, Renard J, Zunder J, Laviolette SR. Hippocampal cannabinoid transmission modulates dopamine neuron activity: impact on rewarding memory formation and social interaction. Neuropsychopharmacology. 2015 May;40(6):1436-47. 

5: Goutagny R, Loureiro M, Jackson J, Chaumont J, Williams S, Isope P, Kelche C, Cassel JC, Lecourtier L. Interactions between the lateral habenula and the hippocampus: implication for spatial memory processes. Neuropsychopharmacology. 2013 Nov;38(12):2418-26.

6: Loureiro M, Cholvin T, Lopez J, Merienne N, Latreche A, Cosquer B, Geiger K, Kelche C, Cassel JC, Pereira de Vasconcelos A. The ventral midline thalamus (reuniens and rhomboid nuclei) contributes to the persistence of spatial memory in rats. J Neurosci. 2012; 32(29):9947-59.

7: Loureiro M, Lecourtier L, Engeln M, Lopez J, Cosquer B, Geiger K, Kelche C, Cassel JC, Pereira de Vasconcelos A. The ventral hippocampus is necessary for expressing a spatial memory. Brain Struct Funct. 2012 Jan;217(1):93-106.

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Organized by

Comité d'Animation et de Communication  Scientifique de l'INCI
Marie-Pierre Laran-Chich, Etienne Challet, Sylvain Hugel & Stéphane Gasman