Abstract
The location of a brief flash is misperceived when the flash is presented around the time of a saccade. This phenomenon has been studied intensively, but there are still some unanswered questions. In a previous experiment we showed that the saccade target is used as a visual reference when localizing flashes that are presented before or after a saccade. The saccade target is a visual reference, but it also provides direct feedback about the saccade. In the study that we present here we examine whether other visual structures can also be used to improve the accuracy of the perceived location of the flash. In particular we examine whether a border between differently colored backgrounds can be used as a visual reference. Moreover we hypothesize that the perceived location of the flash would always be on the correct background color. This would influence the perceived location whenever the border between the two colors is at a position across which flashes are mislocalized on trials with a uniform background. The results showed that there is indeed an increase in accuracy when the flash was presented before and after the saccade, but when the flashes were presented during the saccade they were readily perceived on the background with a different color. This suggests that visual references other than the saccade target can be used as visual references before and after the saccade, but that they are not effective during saccades.
This research was supported by the Netherlands Organization for Scientific Research (NWO, ALW grant 816-02-017).