Impact of decision and action outcomes on subsequent decision and action behaviors

Abstract

AbstractSpeed-accuracy tradeoff adjustments in decision-making have been mainly studied separately from those in motor control. In the wild however, animals coordinate their decision and action, freely investing time in choosing versus moving given specific contexts. Recent behavioral studies support this view, indicating that humans trade decision time for movement time to maximize their global rate of reward during experimental sessions. Besides, it is established that choice outcomes impact subsequent decisions. Crucially though, whether and how a decision also influences the subsequent motor behavior, and whether and how a motor error influences the next decision is unknown. Here we address these questions by analyzing trial-to-trial changes of choice and motor behaviors in healthy human participants instructed to perform successive perceptual decisions expressed with reaching movements whose duration was either bounded or unconstrained in separate tasks. Results indicate that after a bad decision, subjects who were not constrained in their action duration decided more slowly and more accurately. Interestingly, they also shortened their subsequent movement duration by moving faster. Conversely, we found that movement errors not only influenced the speed and the accuracy of the following movement, but those of the decision as well. If the movement had to be slowed down, the decision that precedes that movement was accelerated, and vice versa. Together, these results indicate that from one trial to the next, humans are primarily concerned about determining a behavioral duration as a whole instead of optimizing each of the decision and action speed-accuracy trade-offs independently of each other.