Oxyopia Abstract

March 19, 2004
Friday, 4 PM
489 Minor Hall

Peter Ulric Tse, PhD
Department of Psychological and Brain Sciences, Dartmouth College
Host: Stanley Klein

Title

"The role of contour discontinuities in visual form/motion processing"

Abstract

My goal is to specify the neuronal circuitry involved in processing contour discontinuities (including junctions, terminators, and regions of high curvature). I will present fMRI and psychophysics data that constrain the circuitry underlying the rapid form-motion interactions underlying visual motion perception. In particular, I will argue that contour discontinuities are used by the motion processing system to solve the problem of what went where. I suggest that area V3a may be a salience map of contour discontinuities that act as "trackable features" that permit a simple solution to the aperture problem, and that contour discontinuities are used by ventral form analysis areas, including V4v and posterior fusiform areas to segment objects in space and time in order to solve the matching problem. Lastly, I will present data that supports the claim that area MT processes motion using a high-level "object trajectory" code, rather than a low-level code, such as motion energy.