Stereopsis from Interocular Spatial Frequency Differences is Not Robust

Abstract

AbstractBased on data obtained using one-dimensional noise patterns, Tyler and Sutter (1979). (Vision Research, 19, 859–865) concluded that stereoscopic tilt can result from an interocular spatial frequency difference in the absence of consistent horizontal disparity. We tested stereopsis using two-dimensional random-dot patterns that were bandpass filtered to contain 1.0 octave bands of spatial frequency with means that differed between the two eyes. With vertical, one-dimensional stimuli we replicated the results of Tyler and Sutter. However, stereoscopic tilt was not perceived based on spatial frequency differences alone when the monocular images contained as little as a ±14 deg range of orientation variation. In addition, model simulations demonstrate that the modest stereoscopic performance produced by interocular spatial frequency differences in one-dimensional noise patterns are predicted by random disparity correlations at the pattern edges. These observations lead to the conclusion that stereopsis from frequency differences in the absence of pointwise disparity correlations does not reflect a special processing capability of human vision but is an artifact associated with one-dimensional stimuli. As such, it plays no role in stereoscopic analysis of the natural environment. Copyright © 1996 Published by Elsevier Science Ltd