Our new study on neurobiology of stress-driven food intake.
www.nature.com/articles/s41...

In mice, PFC controls lateral hypothalamus through a multi-branched network. Stress causes differential plasticity across branches, priming the network to promote bingeing. #stresseating

Thanks to the whole team and in particular to @clementsolie.bsky.social who drove this work from the ground up, and to Bruno Delord ( @ISIR - Institut des Systèmes Intelligents et de Robotique), for developing the computational models that gave it its theoretical backbone.

See also @cnrs.fr press release www.cnrs.fr/fr/presse/le..., (thanks to Aurélie Meilhon). It would not have been possible without the work of the whole team at @espciparispsl.bsky.social, @cnrsbiologie.bsky.social , @cnrs.fr

Yet the relationship is bidirectional – and this is where it gets very interesting: manipulating dopamine activity before the social experience reshapes the entire group structure.

A social role is not a stable trait — it is a dynamic position within a collective system.

Striking sex-dependence. Male triads develop worker-scrounger specialisation driven by competition. Female triads remain homogeneous with almost all individuals adopting storer profiles. Introduce one male into a female group and specialisation emerges, including in the females.

Striking sex-dependence. Male triads develop worker-scrounger specialization driven by competition. Female triads remain homogeneous with almost all individuals adopting storer profiles. Introduce one male into a female group and specialization emerges, including in the females.

These roles emerge from the interplay between individual predispositions – tendency to explore versus exploit – and the contingency of early social interactions. The same individual, in a different group, will adopt a different role. Social context is not a backdrop; it is a cause.

Using behavioral tracking, neural recordings and modeling, we found 3 distinct roles emerging spontaneously: Workers, who produce food ; Scroungers, who exploit the efforts of others; and Storers, who press the lever frequently but delay food retrieval, remaining outside the competitive dynamic.

Dopaminergic mechanisms of dynamical social specialization - Nature Longitudinal tracking of mice reveals that stable, specialized social roles emerge spontaneously within groups during a foraging task, with dopaminergic activity in the ventral tegmental area driving ...

New paper in Nature, @nature.com (go.nature.com/4c4OjCj) : how do social roles emerge in groups of near-identical individuals ? we find that they are neither predetermined nor fixed.

4/4 Without any explicit “context” label, a neural-network RL agent trained by TD learning reproduces both rule-specific strategies and the remapping. This suggests remapping can emerge from standard learning dynamics via representation change. So remapping may be an emergent property.

3/4 Instead, DA signals are best captured by different RPE-like variables computed over the currently learned action representation, not one fixed RPE. In short: the “error” DA reports changes with how the animal is currently defining the action.

2/4 Same movements, different reward rules in the same mouse. In a self-paced 3-target foraging task in freely moving mice, nucleus accumbens dopamine (fiber photometry) shows rule-dependent remapping. Model comparison suggests a fixed, representation-invariant RPE can’t explain DA across rules.

1/4 When rules change, dopamine (DA) changes what it calls an “action”.
New bioRxiv version: “Dopamine tracks adaptive learning of action representations”.
www.biorxiv.org/content/10.1...
This project brought together Maxime Come’s PhD work and Arnaud Lespart’s postdoctoral work in our lab.

Congratulations Lauren

Sleep-dependent infraslow rhythms are evolutionarily conserved across reptiles and mammals Nature Neuroscience - Bergel et al. show that an infraslow rhythm connecting the brain and body during sleep is shared by lizards, mammals and birds, revealing an ancestral process and reshaping...

⚠️ New paper alert and what a way to end 2025! 🎉
Happy to share our story “Sleep-dependent infraslow rhythms are evolutionarily conserved across reptiles and mammals.” published today in Nature Neuroscience.

Sleeping dragons 🦎 and functional ultrasound!
Read the full paper here: rdcu.be/eWJHb 1/8

Congrats, well deserve

You just finished your PhD and you are looking for a postdoc to study stress-dependent modulation of learning. We are using the powerful fly model to understand the underlying circuits and mechanisms. You can apply here:
emploi.cnrs.fr/Offres/CDD/U...

Lauren Reynolds

Big news for @laurenmac.bsky.social !
2025 is quite a year: CNRS position + ERC Starting Grant
Her project DeMARRe will study how adolescent exploration & risk-taking shape neural circuits and resilience in adulthood.
@cnrs.fr @espciparispsl.bsky.social
www.insb.cnrs.fr/fr/personne/...

Brain Surfaces of 70 primate species

1
To predict the behaviour of a primate, would you rather base your guess on a closely related species or one with a similar brain shape? We looked at brains & behaviours of 70 species, you’ll be surprised!

🧵Thread on our new preprint with @r3rt0.bsky.social , doi.org/10.1101/2025...

Alcool et nicotine : un même circuit cérébral à l’origine de la récompense et de l’anxiété

👋 @cnrs-paris.bsky.social @espciparispsl.bsky.social
✍️ @faurelab.bsky.social & Fabio Marti
👉 Lire l'article dans buff.ly/vE1j6LP
buff.ly/fD5DOxu

Congratulations to first author Tinaïg Le Borgne for her outstanding work and Fabio marti for leading this project. Many thanks as well to our collaborators across @espciparispsl.bsky.social , @cnrsbiologie.bsky.social, @sorbonne-universite.fr and beyond!

Nicotine and alcohol seem very different, but they converge on the same circuit. Both activate NAc-projecting dopamine neurons and inhibit those projecting to the amygdala. We show that this shared loop shapes reward and emotion, helping explain their high co-use.

A circuit-level explanation for nicotine’s dual impact: Nicotine activates VTA→NAc dopamine neurons (reward), but this comes at a cost: It triggers a GABAergic feedback loop that inhibits VTA→amygdala neurons (emotion).
One drug, the dopaminergic circuits, 2 effects: reinforcement + negative affect.

Nicotine engages a VTA-NAc feedback loop to inhibit amygdala-projecting dopamine neurons and induce anxiety-like behaviors - Nature Communications Drugs of abuse exert both motivational and emotional effects. Here, the authors show that nicotine and ethanol activate a VTA–NAc loop that inhibits dopamine neurons projecting to the amygdala, thereb...

Nicotine doesn’t just “turn on” the brain’s reward circuits — it reshapes them. Our new paper in Nature Communications shows that activating reward-linked dopamine neurons also sets off a feedback loop that drives negative emotional states.
www.nature.com/articles/s41...

Slowing the drive: A new regulatory break for nicotine reward-related behaviors In this issue of Neuron, Jehl et al. developed a “suicide” antagonist to demonstrate that the interpeduncular nucleus acts as a regulatory controller of nicotine reward-related behavior through connec...

Our work on the role of the interpeduncular nucleus in nicotine reward ( www.cell.com/neuron/abstr... ) is featured in a Neuron Preview ! Brandon J Henderson highlights how a new regulatory circuit controlling nicotine reinforcement has been uncovered. www.cell.com/neuron/abstr...

Yesss! So happy to see this, totally deserved!

Embodiment of an artificial limb in mice Body ownership disorders can be triggered by disease or body damage in humans. This study shows, using an automated, videography-based procedure, that mice also display quantifiable behavioral markers...

Our work on rubber hand embodiment in mice is out @plosbiology.org! We show that just like in humans, visuo-tactile pairing can lead mice to an embodiment-like behavior with respect to an artificial limb.

Direct and indirect striatal projecting neurons exert strategy-dependent effects on decision-making In the dorsomedial striatum, d-SPNs increase risk seeking, while iSPNs amplify the value of large gains in decision making.

Nouvel article avec mes ami-es belges E. Chaves et A. de Kerchove où on décrit l'effet de l'activation de populations de neurones du striatum sur les stratégies de décision. On a essayé de sortir d'une définition "par l'expérimentateur" de la performance des souris.

www.science.org/doi/10.1126/...

Sequential and independent probabilistic events regulate differential axon targeting during development in Drosophila melanogaster Nature Neuroscience - The developmental origin of behavioral individuality is unclear. The authors show that a temporal sequence of genetically encoded stochastic mechanisms explains variation in...

Hot off the press:
The excellent Maheva Andriatsilavo and colleagues show how a temporal sequence of stochastic molecular mechanisms allow the emergence of stereotyped individualised neuronal circuits. Just published in Nature Neuroscience:
rdcu.be/ek010

I have an opening in my lab for a postdoctoral fellow to work on projects that relate to the mechanisms of neurotransmitter release by dopamine neurons and/or on how inflammatory signals infuence the functionning of these neurons. Please share.