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A growing body of evidence suggests that decision-making and action execution are governed by partly overlapping operating principles. Especially, previous work proposed that a shared decision urgency/movement vigor signal, possibly computed in the basal ganglia, coordinates both deliberation and movement durations in a way that maximizes the reward rate. Recent data support one aspect of this hypothesis, indicating that the urgency level at which a decision is made influences the vigor of the movement produced to express this choice. Here we investigated whether conversely, the motor context in which a movement is executed determines decision speed and accuracy. Twenty human subjects performed a probabilistic decision task in which perceptual choices were expressed by reaching movements toward targets whose size and distance from a starting position varied in distinct blocks of trials. We found strong evidence for an influence of the motor context on most of the subjects’ decision policy but contrary to the predictions of the “shared regulation” hypothesis, we observed that slow movements executed in the most demanding motor blocks in terms of accuracy were often preceded by faster and less accurate decisions compared to blocks of trials in which big targets allowed expression of choices with fast and inaccurate movements. These results suggest that decision-making and motor control are not regulated by one unique “invigoration” signal determining both decision urgency and action vigor, but more likely by independent, yet interacting, decision urgency and movement vigor signals.NEW & NOTEWORTHYRecent hypotheses propose that choices and movements share optimization principles derived from economy, possibly implemented by one unique context-dependent regulation signal determining both processes speed. In the present behavioral study conducted on human subjects, we demonstrate that action properties indeed influence perceptual decision-making, but that decision duration and action vigor are actually independently set depending on the difficulty of the movement executed to report a choice.

Erratum inCorrigendum to "Decision urgency invigorates movement in humans" [Behav. Brain Res. 382 (2020) (1-12) 112477].; International audience; Recent work in highly trained monkeys suggests that decision-making and motor control are linked processeswhose regulation by urgency allows reward rate optimization. However, such urgency-based mechanism mightbe species-specific and/or a consequence of practice. Here I show that the unified regulation hypothesis exists innaïve human subjects. Seventeen volunteers performed a reach decision task in which blocks of trials encouragedeither risky or conservative choices. Participants performed at least two sessions in which they were indirectlymotivated to maximize their reward rate. Results show that subjects’ accuracy criterion decreased over timewithin each trial, and that decisions were earlier and less accurate in fast than slow blocks, with a larger differencein session #2 compared to session #1. A simple model in which sensory information is combined with agrowing urgency signal captured these effects. Crucially, arm and eye movement vigor systematically increasedas decision duration increased within blocks and the block-dependent decision policy strongly predicted thekinematics of reaching movements. These results suggest a practice-independent mechanistic link for establishingthe unified control of human decision timing and action vigor in order to optimize the rate of reward.