Neurocomputational account of how the human brain decides when to have a break

Motivation, Brain and Behavior Laboratory, Physiological Investigations of Clinical Normal and Impaired Cognition Laboratory, Centre de NeuroImagerie de Recherche, Brain and Spine Institute, Hôpital de la Pitié-Salpêtrière, 75013 Paris, France.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 01/2013; 110(7). DOI: 10.1073/pnas.1211925110
Source: PubMed


No pain, no gain: cost-benefit trade-off has been formalized in classical decision theory to account for how we choose whether to engage effort. However, how the brain decides when to have breaks in the course of effort production remains poorly understood. We propose that decisions to cease and resume work are triggered by a cost evidence accumulation signal reaching upper and lower bounds, respectively. We developed a task in which participants are free to exert a physical effort knowing that their payoff would be proportional to their effort duration. Functional MRI and magnetoencephalography recordings conjointly revealed that the theoretical cost evidence accumulation signal was expressed in proprioceptive regions (bilateral posterior insula). Furthermore, the slopes and bounds of the accumulation process were adapted to the difficulty of the task and the money at stake. Cost evidence accumulation might therefore provide a dynamical mechanistic account of how the human brain maximizes benefits while preventing exhaustion.

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