The optical patterns available to a moving or stationary perceiver-actor specify a variety of important properties of the environment, including the opportunities the environment offers for action. In the optical flow laboratory, we ask how significant aspects of the environment are specified by optical patterns and whether perceiver-actors exploit these patterns in perceiving and acting. Our concern has historically been with navigation: by what optical patterns do we guide our locomotion (steer, stop) through the environment. More recently we have sought to uncover principles of information-action coupling in interceptive tasks. Among the tasks we study are how outfielders run appropriately so as to catch fly balls, how one guides a reach to the side to intercept a ball with one hand, and how one times a volleyball smash.

An additional line of research seeks to uncover the principles by which perceiver-actors learn, i.e., converge on optical variables that allow one to perceive relevant properties and act appropriately in particular task situation, and calibrate, i.e., scale their judgments and actions appropriately to the environment.

Faculty: Bruce Kay, Claire Michaels, Michael Turvey

CESPA Fellow: Nam-Gyoon Kim

Graduate Students: Ryan Arzamarski, Alen Hajnal, Steven Harrison

Fajen, B. R. & Kim, N.-G. (2002). Perceiving Curvilinear Heading in the Presence of Moving Objects. Journal of Experimental Psychology: Human Perception and Performance, 28, 1100-1119.

Kerzel, D. Hecht, H., & Kim, N.-G. (2002). Time-to-passage judgments on circular trajectories are based on relative optical acceleration. Perception & Psychophysics. 2001, 63 1153-1170.

Kim, N-G., Fajen, B., & Turvey, M. T. (in press). Perceiving circular heading in noncanonical flow fields. Journal of Experimental Psychology: Human Perception and Performance.

Michaels, C. F., Zeinstra, E., & Oudejans, R. R. D. (2001). Information and action in timing the punch of a falling ball. Quarterly Journal of Experimental Psychology, 54A, 69-93.

Zaal, F. T. J. M., & Michaels, C. F. (2003). The information for catching fly balls: Judging and intercepting virtual balls in a CAVE. Journal of Experimental Psychology: Human Perception and Performance, 29, 537-555.