People take Newtonian physics into account in sensorimotor decisions under risk

People skillfully manipulate objects on a daily basis, despite uncertainties in both their perceptual inferences and action outcomes. As actions lead to consequences, every movement subject to uncertainty becomes a decision under risk. Such sensorimotor decisions have been shown to follow the predictions of expected utility theory contrary to economic decisions, which systematically fail to maximize expected gains. However, as object manipulations are inescapably governed by the laws of physics, the question arises, how people act under such circumstances. Here, participants slid pucks to targets for gains and losses within a virtual environment, enabling the subjects to interact with an actual standard hockey puck while viewing its trajectory through a head-mounted display. As this novel setup enables subjects to interact with a real-world object through the use of motion capturing, we ensure that subjects have an immersive, naturalistic experience while playing our puck sliding game. In this task, variability inherent in sensorimotor control interacts with the physical relationships governing objects’ kinematics under the influence of friction embedded in an economic decision. Therefore, our task features a unique interaction between three cognitive faculties: 1. Economic decision-making, 2. Sensorimotor control and 3. Intuitive physics. We construct an ideal actor model based on statistical decision theory including the kinematics of sliding and show that subject behavior is in coherence with its predictions. Taken together, this demonstrates that subjects use their sensorimotor uncertainty and its interaction with physical relationships and economic demands of the task in guiding their actions.