Secondary motor cortex tracks decision value during the learning of a non-instructed task

Augusto E(1), Kouskoff V(1), Chenouard N(1), Giraudet M(1), Peltier L(1), de
Miranda A(1), Louis A(1), Alonso L(1), Gambino F(2).

Author information:
(1)Institut Interdisciplinaire de Neurosciences (IINS), University Bordeaux,
CNRS, IINS, UMR 5297, 33000 Bordeaux, France; Centre Broca Nouvelle-Aquitaine,
146, rue Léo-Saignat, 33076 Bordeaux, France.
(2)Institut Interdisciplinaire de Neurosciences (IINS), University Bordeaux,
CNRS, IINS, UMR 5297, 33000 Bordeaux, France; Centre Broca Nouvelle-Aquitaine,
146, rue Léo-Saignat, 33076 Bordeaux, France. Electronic address:
.

Optimal decision-making depends on interconnected frontal brain regions,
enabling animals to adapt decisions based on internal states, experiences, and
contexts. The secondary motor cortex (M2) is key in adaptive behaviors in expert
rodents, particularly in encoding decision values guiding complex probabilistic
tasks. However, its role in deterministic tasks during initial learning remains
uncertain. Here, we describe a self-initiated deterministic task requiring mice
to use their forepaws to make choices without guiding cues. Our findings reveal
that spontaneous decisions follow a « race » model between actions, which uncovers
underlying decision values. We use in vivo microscopy and modeling to show that
M2 neurons in male mice exhibit persistent activity-encoding decision values
that predict action-selection probabilities. Optogenetic inhibition of the M2
reduces the reversal performance and alters the decision value. Additionally,
updates in decision values determine the rate at which learning is reversed.
These results highlight the use of decision values by the M2 to adapt choice
during initial learning without instructive cues.

Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.

DOI: 10.1016/j.celrep.2024.115152
PMID: 39764851 [Indexed for MEDLINE]

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

Auteurs Bordeaux Neurocampus