Abstract
Perceptual filling-in (PFI) and motion-induced blindness (MIB) are two phenomena in which perceptually salient stimuli repeatedly disappear and reappear after prolonged viewing. The perceptual blindness of the target in PFI was assumed to be caused by boundary adaptation and fast interpolation, while that in MIB was attributed to high-level (e.g., attention) processes. We have shown previously that PFI and MIB may share a common mechanism when factors such as eccentricity, contrast, and perceptual grouping are taken into consideration (Hsu, Yeh, & Kramer, Vision Research, in press). Here we examined further the role of surface competition in PFI and MIB. In Experiment 1, stereo-depth information was added to the stimulus pattern to create depth ordering between the target and the moving background. When the target was in front of the background, its fading duration was shorter than when it was behind the background. The perceptual occlusion of the target by the background increased the duration of target fading regardless of how deep the target was behind the background. In Experiment 2, surface competition between the target and the background was induced by a Kanizsa square in which the strength of the induced surface was manipulated by using different luminance values of the Kanizsa inducers. The fading of the target was increased when it was on a stronger induced surface compared to a weaker one. In Experiment 3, the size of the targets on surfaces of different depth was manipulated to investigate whether the boundary adaptation, a presumed mechanism of PFI, occurred with depth ordering. Results showed that when the target and the background were not on the same surface, the fading of the target was free from the influence of the boundary between the target and the background. A theoretical framework considering the role of surface competition plays during the process of perceptual fading was provided to account for PFI and MIB.
Supported by the National Science Council of Taiwan, NSC92-2413-H-002-026