Lleras Alejandro, Moore Cathleen M
Department of Psychology, The University of Illinois at Urbana-Champaign, 603 East Daniel St., Champaign, IL 61820, USA.
Psychol Sci. 2006 Oct;17(10):876-81. doi: 10.1111/j.1467-9280.2006.01797.x.
A perceptually filled-in surface, such as occurs during sustained attention to a peripheral stimulus (Troxler fading), can be functionally equivalent to a physically presented stimulus. Observers failed to detect probes that were presented in the location of a filled-in surface that had the same surface attributes as the probes; this was true even though, physically, the probes contrasted with the background. Probe stimuli with surface characteristics different from those of the filled-in surface were detected more often, though not quite as often as when there was no filled-in surface. Together, these findings support the idea that there are two components in perceptual filling: a neural filling-in component and a sustained-attention component, which actively suppresses perceptual processing at the filled-in location. More broadly, they illustrate the interplay of basic visual mechanisms in the creation and representation of visual surfaces and in the coding and detection of changes to these surfaces.
