Abstract
A recent study by Lou (1999) looked at Troxler fading and concluded that it is driven by attentional selection, as well as by display properties such as eccentricity. The present study sought to extend Lou's findings. Two specific questions were addressed. First, how does the fading depend on the structure of the attended objects? Second, is the duration of the fading influenced by attention? Green and magenta discs were presented peripherally on the display. At the beginning of each trial, participants were asked to attend to the discs of one color. Our results only partially replicated Lou's. In particular, while green discs faded selectively when subjects attended to green, green discs also faded selectively when subjects attended to magenta. Second, the fading did appear to depend on the structure of the objects. Finally, the duration of the fading appeared to be longer for attended discs than for unattended discs, although this was only observed for green discs. First, we believe that the failure to completely replicate Lou 's findings was caused by the fact that our color contrasts were different from his and it may be difficult to peripherally attend to low-contrast stimuli in the presence of high-contrast stimuli. Second, while the pattern of results regarding the relation of the fading to attentional selection was informative, the data were noisy. Follow-up experiments with simpler designs are underway. The goal is to develop more objective measures of the fading and to characterize the locus of the Troxler fading.