The “fluttering heart” and spatio-temporal characteristics of color processing—I: Reversibility and the influence of luminance

Abstract

The classic phenomenon of the “fluttering heart” was investigated in two experiments. It was demonstrated that the effect consists of a genuine delay and not a phase difference. Its reversibility presents serious problems for two earlier explanations based on the dependence of perceptual latencies on wave-length and the differential latencies of the rod and cone apparatus, respectively. It was further shown that a luminance difference between target and background is neither a sufficient nor a necessary condition, but that a color difference is necessary. It was suggested that interactions between the color processing mechanisms across the chromatic border are involved.