A new article about the mechanism of timed behavior, collaboration between the INMED and the IRPHE , has recently been published in Proceedings of the National Academy of Sciences (PNAS).
Entitlted “Turning the body into a clock: Accurate timing is facilitated by simple stereotyped interactions with the environment“, this article (published in April) is the result of a colaboration between 2 of our partner institute : the INMED and the IRPHE. The article is signed by Mostafa Safaie (INMED), Maria-Teresa Jurado-Parras (INMED), Stefania Sarno (INMED), Jordane Louis (INMED), Corane Karoutchi (INMED), Ludovic F. Petit (INMED), Matthieu (INMED) O. Pasquet (INMED), Christophe Eloy (IRPHE), and David Robbe (INMED).
Abstract: How animals perceive, or sense elapsed time, is not well understood, especially when considering timescales of a few seconds. One influential idea is that the brain generates a representation of time that serves as an internal clock. Alternatively, animals could take advantage of salient physical features of the environment to develop sequences of movements whose duration approximate the time intervals to estimate.
Methods/Approach. We challenged rats in a time estimation task taking place on a 90 cm-long motorized treadmill. We then manipulated several task parameters to test whether animals could estimate time accurately without performing any motor sequence in a stereotyped manner.
Main results. To reliably estimate time, most animals developed the same motor sequence and seemed incapable to rely on an internal disembodied neuronal clock. Acquiring such embodied strategy to estimate time could be reproduced by a “clock-less” reinforcement learning-based model.
Knowledge gained. Our study challenges the idea that animals rely primarily on internal neuronal clocks to estimate the duration of interval lasting for a few seconds. Time, at behavioral level, should be considered from the viewpoint of sensorimotor activity and affordance.