Accession Number : ADA193076

Title :   Perception of Motion in Statistically-Defined Displays.

Descriptive Note : Annual scientific rept. 1 Oct 86-30 Sep 87,

Corporate Author : NORTHWESTERN UNIV EVANSTON IL CRESAP NEUROSCIENCE LAB

Personal Author(s) : Sekuler, Robert

PDF Url : ADA193076

Report Date : 15 Feb 1988

Pagination or Media Count : 102

Abstract : Though motion perception does depend upon spatially local processes, under certain circumstances global processes make an important contribution. For example, the human visual system can integrate different, spatially-intermingled motion vectors into a global percept of motion in a single direction. Such integrated percepts may offer important clues to the mechanisms of motion perception. To exploit such clues we have followed the tradition of using discrimination performance to probe underlying psychophysical mechanisms. Specifically, we were interested in how easily observers could discriminate between two different global motions when each had resulted from the integration of many different motion vectors. Our stimuli were random dot cinematograms in which each dot took an independent two-dimensional random walk with steps of constant size. The direction any dot moved, from one display frame to the next, was independent of the dot's previous movements as well as the movements of other dots. All dots chose their directions of movement from the same probability distribution.

Descriptors :   *MOTION, *SPATIAL DISTRIBUTION, *VISUAL PERCEPTION, *SPACE PERCEPTION, DISCRIMINATION, FRAMES, GLOBAL, HUMANS, ORIENTATION(DIRECTION), PERCEPTION, PROBABILITY DISTRIBUTION FUNCTIONS, PROBES, PSYCHOPHYSICS, SIZES(DIMENSIONS), STIMULI, VISION, MATHEMATICAL MODELS, COMPUTATIONS, STATISTICAL DISTRIBUTIONS, TWO DIMENSIONAL, DISPLAY SYSTEMS

Subject Categories : Psychology
      Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE