Séminaire de Nicolas Clairis 22/11/2024

Vendredi 22 novembre 2024, 14h30 – Salle Henri Gastaud, INT

Nicolas Clairis (Ecole Polytechnique Fédérale de Lausanne) invité par Christelle Baunez et Andrea Brovelli

Neural and neurometabolic correlates of effort-based decision-making

Abstract: People exhibit significant variability in their willingness to engage in both physical and cognitive efforts. Yet the underlying neurobiological mechanisms driving this variability remain poorly understood. To address this gap, we conducted a series of experiments using functional magnetic resonance imaging (fMRI), proton magnetic resonance spectroscopy (1H-MRS), behavioral decision-making tasks and computational modeling in healthy human subjects to unravel the mechanisms driving inter-individual differences in effort-based decision-making. Our results demonstrate the consistent involvement of the dorsomedial prefrontal cortex/dorsal anterior cingulate (dmPFC/dACC) in energizing the decision to engage in both physical and cognitive efforts. More precisely, we have demonstrated that the activity of the dmPFC/dACC positively correlates with the decision to engage with more difficult physical and cognitive efforts across two fMRI experiments. Furthermore, dmPFC/dACC baseline levels of lactate measured with 1H-MRS correlate with the propensity to engage in physical efforts, an effect mediated by their impact on dmPFC/dACC neural activity during decision-making. Using machine-learning, we could also identify a small set of baseline dmPFC/dACC metabolites comprising glutamate, lactate and aspartate which predicted the motivation to engage in mental effort. Our findings underscore the significant influence of the dmPFC/dACC on motivated behavior and pave the way for a better understanding of the mechanisms driving differences in effort-based decision-making in healthy individuals as well as in patients suffering from motivational alterations.