Facial expressions in mice reveal latent cognitive variables and their neural correlates

Cazettes F(#)(1)(2), Reato D(#)(3)(4)(5), Augusto E(3), Steinfeld R(3), Renart
A(3), Mainen ZF(3).

Author information:
(1)Champalimaud Foundation, Lisbon, Portugal. .
(2)Institut de Neurosciences de la Timone, CNRS and Aix Marseille Université,
Marseille, France. .
(3)Champalimaud Foundation, Lisbon, Portugal.
(4)Institut de Neurosciences de la Timone, CNRS and Aix Marseille Université,
Marseille, France.
(5)Departement BEL, Centre CMP, Mines Saint-Etienne, Gardanne, France.
(#)Contributed equally

Erratum in
Nat Neurosci. 2026 Apr;29(4):1023. doi: 10.1038/s41593-026-02271-7.

Brain activity controls adaptive behavior but also drives unintentional
incidental movements. Such movements could potentially be used to read out
internal cognitive variables that are also neurally computed. Establishing this
would require ruling out that incidental movements reflect cognition merely
because they are coupled with task-related responses through the biomechanics of
the body. Here we addressed this issue in a foraging task for mice, where
multiple decision variables are simultaneously encoded even if, at any given
time, only one of them is used. We found that characteristic features of the
face simultaneously encode not only the currently used decision variables but
also independent and unexpressed ones, and we show that these features partially
originate from neural activity in the secondary motor cortex. Our results
suggest that facial movements reflect ongoing computations above and beyond
those related to task demands and demonstrate the ability of noninvasive
monitoring to expose otherwise latent cognitive states.

© 2025. The Author(s), under exclusive licence to Springer Nature America, Inc.

DOI: 10.1038/s41593-025-02071-5
PMID: 41028294 [Indexed for MEDLINE]

Conflict of interest statement: Competing interests: The authors declare no
competing interests.

Auteurs Bordeaux Neurocampus