The seeing-more-than-is-there phenomenon: implications for the locus of iconic storage.

Abstract

When a target figure is moved back and forth behind a window cut in an opaque screen, more of the figure is seen at a given instant than is physically present. This finding implies that the information presented at one instant is stored in iconic form so that it can be integrated with information presented at a slightly later instant. Two experiments explored the illusion and showed that it can be readily demonstrated under a variety of conditions. A third experiment indicated that it can occur in the absence of appreciable eye movements. This latter finding, together with various supporting argument, is taken as evidence against an explanation of the illusion in terms of the target image being painted across the retina. Rather, it appears that successive sections of the target item are projected onto the same retinal sector. It is difficult to understand how simple photoreceptors can simultaneously retain information presented at one instant and register information presented at a subsequent time without two pieces of information being fused. Therefore, it is concluded that the iconic storage implied by the illusion occurs at a level more central than that of the retinal receptors.