Studies of Visual Perception.
Abstract
This report describes parametric investigations of the spatio-temporal response of the human visual system conducted with various types of concentric targets: concentric sine, concentric cosine, and Bessel-function targets. The major parameters varied in this study were the spatial frequency, temporal frequency, target size, spatial pattern, and adaptation level of the stimulus. It was found that J sub o targets, concentric cosine targets, and parallel sine-wave gratings yield three characteristically different spatial response curves, related to each other approximately by the 0.5 and 1st powers of the spatial frequency. It was found that the mid-frequency modulation sensitivity increases with increasing target size over the range of target sizes studied (up to 16 degrees). Two dimensional fourier analyses of the stimulus patterns appear to provide valuable clues to the explanations of both these results. On the other hand, the high-frequency cutoff (or resolution limit) seems to be essentially independent of target size, provided the target is greater than 1 degree or 2 degrees in diameter.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1967
- Accession Number
- ADA047893
Entities
People
- Donald H. Kelly
Organizations
- SRI International