Size, flux and luminance effects in the apparent motion correspondence process

The effects of the relative size, luminance, and total luminous flux of apparent motion visual stimulus disk elements are studied, using a competitive paradigm. These dimensions can only be studied in pairs and we find that all three pairs have significant correspondence process effects. A comparison of the magnitudes of the effects, however, suggests that size and flux are the dimensions relevant to apparent motion processing, while luminance may not contribute to the correspondence process. Pitting distance against these dimensions in apparent motion tasks, we were able to find effective equivalence scales among them. Finally, interactions were found between the processing of some of these dimensions. The most pronounced interaction effect is that the addition of the size dimension increases the noise in the processing of distance, while size processing is not affected by the addition of the distance cue.