Determinants of the rod and frame effect: The role of retinal size

Abstract

In Experiment 1, base-out prisms were used to alter perceived size and distance to a luminous rod and frame while the retinal size remained unchanged. The rod-and-frame effect (RFE) was the same, whether the display was viewed directly or through the prisms. In Experiment 2, one large and one small rod-and-frame display were placed at distances such that they produced identical retinal angles. This was replicated at three different sets of distances. Perceived size and distance of the large and small frame of identical retinal angle interacted with the observation distance, such that at near distances the large frame was perceived as larger and farther than the small frame while, at far distances, both types of estimates converged to a constant value. In contrast, the RFE was identical for the large and small frames matched in retinal angle, but diminished with distance. In both experiments, the RFE varied precisely with variation in retinal angle. Implications of the role of retinal angle in the RFE and for the interpretation of individual differences were discussed.Previous research (Ebenholtz & Benzschawel, (1977) has established that the magnitude of the rod-and-frame effect (RFE), first investigated by Witkin and Asch (1948), is greatly influenced by the distance between the observer and the luminous frame. Within a range from 1 to 5 m, the RFE approximated a linear inverse function of distance with essentially no RFE at all at 5 m. The question examined in the present paper concerns the mechanisms that conceivably underlie this result.With increasing distance between the visual display and the subject, three changes occur, each of which could, in principle, cause the reduction in RFE. First, the retinal size of the pattern will vary inversely with distance and, assuming that subjects tend to direct their focus toward the center of the frame, there will result a shift in retinal stimulation from peripheral to foveal. Either one or both of these retinal factors, i.e., the size change or the shift to foveal viewing, could contribute to the reduction in magnitude of the RFE. Second, changes in distance, especially within a few meters, will be accompanied by changes i'n apparent distance and, third, at distances beyond about 2 m size constancy, based solely upon the cues of convergence and accommodation, will begin to fail (Leibowitz & Moore, 1966), with the consequence that detectable changes in apparent size will occur. Thus, changes in retinal size, apparent distance, or apparent size, singly or jointly, may be responsible for the effects of distance on the RFE.The research was supported in part by Grant MH 13006. The author is grateful to Jonathan Beers for his aid in directing subjects in Experiment I and to Judith Callan for directing Experiment 2 and for data analysis. 531The following studies explore these possibilities. In Experiment 1, the RFE, obtained when viewing through a pair of base-out prisms, was compared with the RFE determined under normal nonprism viewing. By increasing convergence, the rod...

Absence of depth processing in the large-frame rod-and-frame effect

“…Because of the results of previousstudies (Ebenholtz, 1977;Ebenholtz & Callan, 1980), a drop in RFE with retinal size of frame was expected, but the present data show this trend most clearly for the 22-deg frame tilt. Here (Experiment 6), with the visual angle of the frame equal to 7.2 deg, the RFE actually failed to differ significantly from zero.…”

“…It would seem to be worthwhile to continue the practice (Gogel & Newton, 1975;Wenderoth, 1974) of referring to smallframe phenomena as "illusions," or RFI, and large-frame phenomena as "effects," or RFE (Ebenholtz, 1977).…”

“…Recent studies have failed to disclose any significant role for perceived frame size (Ebenholtz, 1977) or for perceived form (Streibel, Barnes, Julness, & Ebenholtz, 1980), but have provided evidence that retinal size and linear corner elements in the retinal pattern playa determining role. It therefore appears that the extraction of orientation information precedes both size and form-processing stages.…”

The Ponzo illusion and the perception of orientation

“…The evidence for this assertion is a comprehensive series of experiments by Ebenholtz and his colleagues, demonstrating that the magnitude of the rod-and-frame effect increases as the stimulus gets retinally larger (e.g., Ebenholtz, 1977Ebenholtz, , 1985Ebenholtz & Callan, 1980). As the stimulus gets larger, the frame falls more in the periphery.…”

The field dependence/independence cognitive style does not control the spatial perception of elevation

“…The characteristics of the inducing stimulus described above, as well as the methodology and the experimental results for the VPEL discrimination, are closely analogous to those for the VPV discrimination where VPV settings are close to veridical in normally oriented environments but change with the roll tilt of the visual field as a near-linear function of the magnitude of the roll tilt deviation from an erect orientation ( 22º roll 22º; Ebenholtz, 1977;Ebenholtz & Benzschawel, 1977;Howard, 1986;Howard & Templeton, 1966;Li & Matin, 2005a, 2005b, 2005cMatin & Li, 1994b, 1995Morant & Beller, 1965;Wenderoth, 1982;. It is of particular significance here that in both discriminations, subjects display large individual differences that are consistent over long periods (Matin & Li, 1999Witkin, 1949a).…”