Two forms of retinal disparity

Abstract

The retinal disparities in stereograms where the vertical alignment of pairs of homologous points in one eye differs from that in the other eye were found to be more effective than disparities that do not involve that kind of binocular difference. The presence of such "transverse disparities" was found to shorten the time elapsed until perceived depth was reported in four instances. in two simple stereogram pairs and in two different pairs of random dot pattern stereograms. In .an experiment where binocular parallax was in conflict with an effect of past experience. the presente of transverse disparities caused binocular parallax to prevail. The presumption that the amount of perceived depth depends only on the amount of disparity (provided distances from the eyes are unchanged) and not on the configuration in which it manifests itself was found not to hold in stereograms containing transverse disparities.

Learned stimulation in space and motion perception.

“…Thus, only the different forms of the binocular configurational difference could have been responsible for the different results in these experiments (Wallach & Bacon, 1976).…”

“…But a particular distance difference is configurationally more conspicuous when the absolute distance between the images is short rather than long. Lindauer and I (Wallach & Lindauer, 1962) found that identical disparities resuited in larger perceived depth when they were associated with shorter absolute distances than with larger absolute distances. The more conspicuous configurational differences produced greater depth.…”

“…The following articles for which the original sources are cited in the text were reprinted in Wallach's 1976 book On Perception: Wallach (1968) ;Wallach, Frey, and Bode (1972); Wallach and Huntington (1973); Wallach and Lindauer (1962); Wallach, Moore, and Davidson (1963);and Wallach, Stanton, and Becker (1974). ocular pursuit but follow horizontal motions that are given as image displacement should look more horizontal than they really are, and that is what Bacon found.…”

Anisotropies in the perception of stereoscopic surfaces: The role of orientation disparity

“…Wallach and Bacon (1976), and Gillam et al (1984,1988) found that the latency to perceive depth was longer when stimulus disparities were changing in a horizontal direction (creating expansion-compression patterns of disparity) than when they were changing in a vertical direction (creating shearing patterns of disparity). In Wallach and Bacon's (1976) first experiment, there is a larger component of orientation disparity present in the "transverse" disparity stimulus, which they reported was easier to see, than in their "superpositional" stimulus (their Fig. 2) which is essentially a horizontal expansion of one eye's view, and possesses only a small component of orientation disparity along the oblique.…”

“…St~~o~opi~ly-de~ned surfaces which slant or curve about a horizontal axis are often perceived more readily, and have more apparent slant or curvature, than surfaces which slant or curve about a vertical axis (Wallach & Bacon, 1976;Rogers & Graham, 1983;Gillam, Flagg 62 F&day, 1984;Gillam, Chambers 4% Russo, 1988;Rogers & Cageneifo, 1989;Mitch&on & McKee, 1990;Mitchisan & Westheimer, 1990;Gillam 8z Ryan, 1992). Although there are signif?cant individual differences in the magnitude of the effect, studies of the anisotropy have shown that surfaces containing disparities that change in a direction orthogonal to the axis joining the two eyes [i.e.…”