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

Attenuation of the rod-and-frame effect (RFE) with depth separation (Gogel & Newton, 1975) was investigated with the rod and frame in either intersecting or parallel depth planes (PDP). In the former case, in which either the top of the rod or the frame was inclined 45 deg away from the observer, no attenuation was found for frames projecting a retinal angle of 39.2 or 13.5 deg. In the PDP paradigm, the rod was optically 60 cm nearer the observer than was the frame. The depth adjacency effect of Gogel and Newton was replicated, but only for small retinal angles (7.2 and 6.8 deg) of the frame and for a 15-deg frame tilt, but not for larger retinal angles (39.2 and 12.7 deg) or for frames tilted at 22 deg. The absence of attenuation with depth separation in large frames and its presence in small frames is consistent with the identification of these phenomena with properties of the ambient and focal visual systems, respectively (Leibowitz & Post, 1982).