Braking bad: Arousal influences the visual guidance of braking

摘要

Arousal has been shown to influence perceptual judgments as well as the execution of online motor control (e.g., as in the case of choking under pressure). The current study investigated whether arousal also influences the online control of a common visually-guided action over time. Participants performed either an emergency (Experiment 1) or regulated (Experiment 2) braking task with the goal of stopping before colliding with a target. For the emergency braking task, participants applied maximum braking pressure and once braking pressure was applied it could not be released. For regulated braking, participants were able to adjust braking pressure as needed over time. Participants performed one braking task after arousal induction or not. We were primarily interested in testing the hypothesis of whether arousal altered the calibration between visual information and action execution. We hypothesized that arousal would indeed act as a soft constraint on motor control (Harrison, Frank, & Turvey, 2016). Behaviorally, we hypothesized that arousal would lead to faster initiation of braking and less crashing, by influencing the perceptual-motor calibration of braking with respect to visual information. Results from emergency braking supported our hypotheses a?? anxious participants initiated braking sooner and crashed less often. However, when performing regulated braking, anxious participants initiated braking sooner but crashed more often. Overall, the results demonstrated that participants were more conservative in their braking, but that this actually led to a greater chance of crashing when braking was continuously regulated because of their greater reliance on current braking. These results imply that emotions act to alter the calibration between perception and action. Future work may benefit from integrating continuous, physiological indicators of emotional states.