A general informational variable for action-related perception
Michael A. Riley
Center for Cognition, Action, & Perception
University of Cincinnati
Abstract: I will present research–some established, some preliminary–supporting the hypothesis that perceivers use multimodal informational variables that relate actions to their optical consequences in three domains of action-related perception: Embodied distance perception, perception of functional properties of hand-held object, and perception of action-scaled affordances. The research in each domain implicates a specific instance of a generic type of multimodal variable that relates action (e.g., energy expenditure, applied muscular torque, ground reaction force, propulsive force during locomotion) to the optical consequences of the action (e.g., translational, lateral or vertical optic flow, the visible kinematics of the movement of virtual counterparts of hand-held objects). We have developed quantitative, predictive models of how multimodally specified effort (an informational variable relating energy expenditure to optic flow) constrains perceived distance; (2) multimodally specified inertia (an informational variable relating applied muscular torque to the apparent responsiveness of hand-held objects to that torque) constrains multimodal (vision + haptic) heaviness perception; and (3) multimodally specified propulsion (an informational variable relating muscular propulsive force to vertical optic flow) constrains perception of action-scaled affordances. Our experiments use virtual reality and motion capture to dissociate these multimodal informational variables from the actions that give rise to them, allowing us to modify the usual optical consequences of an action and create states of mis-calibration that reveal a perceiver’s normal reliance on the hypothesized informational variables. The importance of this research is the potential for revealing a general principle for perceptual tasks that have previously been considered distinct and have typically been pursued independently by different laboratories working in different disciplines, using different methods and approaches.
Bio: Michael Riley received his B.A. in Psychology from the University of Louisiana-Monroe in 1994 and his Ph.D. in Experimental Psychology from the University of Connecticut in 1999. He started as an Assistant Professor in the Psychology Department at the University of Cincinnati in 2000, where he now holds the rank of Professor and serves as Director of the Center for Cognition, Action, and Perception. His research has been funded by the U.S. Army Medical Research and Materiel Command and the National Science Foundation.