Dynamic Occlusion (How Information Tells You About What Is Happening Now)

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Kinematics Can Specify Dynamics Progressive Occlusion (Gibson et al, 1969; Kaplan, 1969) Dynamical Event: One surface going out of view behind another (becoming progressively occluded but continuing to exist) Kinematic Information: Deletion of optical texture at the leading edge, accretion of optical texture at the trailing edge (optical elements going being destroyed and created) Perception: the dynamical event ‘persisting surface becoming occluded and de-occluded’ Judgments: people never report the accretion or deletion, but the occlusion Multiple object tracking: can still be tracked through an occlusion but not an actual disappearance/reappearance (Scholl & Pylyshyn, 1999) Scholl & Pylyshyn (19990

Multiple Object Tracking Survives Occlusion but not Disappearing MOT: Occlusion Baseline http://www.yale.edu/perception/Brian/demos/MOT.html

People track objects Occlusion specifies moving in and out from behind something Implosion/explosion specifies coming in and out of existence James J Gibson (1966) Scholl, B. J., & Pylyshyn, Z. W. (1999). Tracking multiple items through occlusion: Clues to visual objecthood. Cognitive Psychology, 38, 259-290.

The particular kinematic pattern (optical texture elements going out of view along a leading edge, into view a long a trailing edge) is detected and leads to the perception of ‘one object passing in front of another with both continuing to exist’