TRANSSACCADIC UPDATING AND FEATURE OVERWRITING

The present study investigated mechanisms of transsaccadic object updating. We have previously shown that the pre-saccadic representation of the saccade target object is overwritten by its post-saccadic representation when visual stability is established (Tas, Mordkoff, & Hollingworth, 2021). However, other studies have shown that the pre- and post-saccadic representations are instead integrated across saccades (e.g., Wolf & Schütz, 2015). An important difference between these studies was the task instructions. In our previous experiments, we asked participants to report either the pre- or the post-saccadic feature of the saccade target. However, studies which found integration effects asked participants to report the feature of the saccade target without specifying different states (pre-saccadic or post-saccadic) which may promote an integration mechanism. The present study tested this possibility. Participants executed a saccade to a colored disk. On half of the trials, the saccade target’s color was changed by 15° during the saccade. After each trial, participants were asked to report the color of the saccade target object by clicking on the corresponding color on a color wheel (integration block). Participants also completed two blocks where they saw the saccade target either only pre-saccadically or only post-saccadically. In the current study, when we tested the fit of the response distributions of the integration trials, finding that data were best explained by a single distribution of responses at the post-saccadic color value. We also tested whether integration trials resulted in better performance compared to the best of the pre-saccadic only (PreOnly) or post-saccadic only blocks (PostOnly). We found no evidence for cue integration: Color reports were not significantly more precise in the integration block compared to the best single performance. Together, these findings failed to show support for integration, but found support for overwriting in nearly 100% of the trials.