Abstract
Two broad theories of transsaccadic object persistence and visual stability posit, on the one hand, that object persistence depends on the mapping of spatial pointers assigned to the pre- and post-saccadic objects (e.g., Cavanagh et al., 2010; Pylyshyn, 2000) and, on the other, that object persistence depends on the retention and comparison of object surface features across the saccade (e.g., Currie et al., 2000; Hollingworth et al., 2008). We tested these two hypotheses by probing the role of surface feature information in object persistence across a saccade. On each trial, a saccade target was shifted spatially during the saccade to that object. In previous work (Deubel et al., 1996), perception of shift direction was poor when the post-saccade object could be considered a continuation of the pre-saccade object (no gap condition), leading to updating of the pre-change position of the target object. On the other hand, when object continuity was disrupted by removing the target briefly after the saccade (gap condition), perception of shift direction was highly accurate. In the latter case, the post-saccade target was perceived as a new object, leading to efficient comparison between the pre- and post-saccade locations. Thus, sensitivity to transsaccadic shifts can be used as a measure of object continuity. In the present study, we included additional conditions in which the surface features of the saccade target were changed across the saccade. We replicated the original Deubel et al. findings: Shift detection performance was significantly better in the gap condition than in the no gap condition. Importantly, changing the target object's surface features across the saccade improved sensitivity to position shifts relative to the no gap condition, consistent with the view that transsaccadic memory for object surface features plays an important role in object persistence.