Intuitive sensorimotor decisions under risk take Newtonian physics into account

The success of our interactions with objects in natural tasks depends on generating motor actions, which are subject to sensorimotor variability, the objects physical properties, which are governed by the laws of kinematics, and the costs and benefits associated with the actions outcomes. Therefore, such interactions jointly involve sensorimotor control, intuitive physics, and decision-making under risk. Here, we devised a mixed reality experiment, which allows investigating human behavior involving the interaction of all three of these cognitive faculties. Participants slid pucks to target areas associated with monetary rewards and losses within an immersive, naturalistic virtual environment. In this task, signal-dependent variability inherent in motor control interacts non-linearly with the physical relationships governing objects motion under friction. By systematically testing generative models of behavior incorporating different assumptions about how participants may generate the slides, we find decisive evidence that participants decision under risk readily took their individual motor variability and Newtonian physics into account to gain monetary rewards without relying on trial by trial learning. Author summaryHumans are exceptionally proficient at manipulating objects in natural tasks. This skill requires integrating three cognitive faculties: 1. Sensorimotor-control, subject to inherent uncertainty and variability; 2. Intuitive physical reasoning as object manipulations are subject to physical dynamics; 3. Economic decision-making when actions have outcomes with monetary consequences. Here, we show that in a naturalistic, immersive object manipulation task, human participants plan their movements by taking into account how their sensorimotor variability interacts with the physical dynamics of object manipulation to optimize economic outcomes. Therefore, our findings suggest that in everyday naturalistic interactions with the world, humans can integrate these three cognitive faculties.