Integrating situational probability and kinematic information when anticipating disguised movements

Abstract

ObjectivesThe current study sought to examine the relative contributions of kinematic and situational probability information to anticipation using different levels of disguised kinematics. More specifically, it was tested whether the weighting of the informational sources (kinematic vs. probabilistic) shifts relative to the certainty of the available kinematic information. Design and MethodHuman-like avatars were generated performing penalty throws and displayed in a virtual reality environment. The ambiguity of the kinematic information available from the avatars was systematically manipulated using linear morphing between genuine and disguised throws. In a perceptual classification task, trained novice observers (N = 23) were asked to classify as quickly and accurately as possible whether observed throws were either genuine or disguised. In addition, information about the performer’s action preferences was also systematically manipulated by explicitly informing participants about the performer’s AP to disguise their throw (25%, 50%, and 75%). ResultsParticipants’ response behavior showed that observers relied more heavily on the probabilistic information when the kinematics were ambiguous. For the AP 25% condition, observers were more likely to report that ambiguous throws were genuine (p < 0.001), whereas they classified the ambiguous throws as being disguised in the AP 75% condition (p < 0.001). ConclusionFindings suggest that observers rely more strongly on non-kinematic (situational probability) information when the reliability of the observable movement kinematics becomes less certain.