Zijiang J. He

时间： 2010-06-03 15:00 - 17:00

地点： 哲学楼103房间

How the visual system represents space determines our perception and action.  From a natural selection standpoint, our terrestrial existence should compel the visual system to utilize the prevalent ground information for space representation.  In this talk, a series of psychophysical studies showing the critical role of the ground surface information for determining space perception in the intermediate distance range will be presented.  From these empirical findings, I will describe a theoretical framework that specifies the shape, and consequence, of our perceptual space for object localization.  Briefly, the perceptual space is determined by two closely linked mechanisms: (i) the visual system’s internal default of the visual space (the intrinsic bias), and (ii) the representation of the ground surface based on external depth information.  The intrinsic bias is very likely derived from our past experiences (memory) in the visual world.  It takes the approximate form of an implicit slant surface, and dictates space perception in conditions of insufficient depth information (e.g., in the dark).  The ground surface representation mechanism is responsible for integrating local texture information on the ground to form a reliable global ground surface representation.  In a rich cue environment, the ground surface representation mechanism predominates and ensures accurate object localization in 3-D space.

2010-06-03

2010-06-03