• crowding
• extrapolation of visual features
• occlusion

One challenge of the visual system is to reconstruct the external objects on the face of changes of their visibility and to tolerate the possibility that objects could temporarily disappear from sight once they go behind an occluder. Previous literature have demonstrated our remarkable tolerance for such temporary absences of visual information. However, it's been noted that once objects disappear behind occluders, much of their modal properties —like shape, color, and texture—are lost, leaving their positional information intact.

In this research we sought to understand the underlining mechanisms postulating that extrapolation of moving objects behind occluders might occur relatively early in the visual cascade. To this end we pitied extrapolation of motion against a well-known visual phenomenon which occurs somewhat in the middle of the visual cascade: crowding. Crowding is a phenomenon whereby the features of a peripheral object are blended with the features of flanking items. To this end we asked whether an item which disappeared behind an occluder could act as a flanker of a visible target.

If that were the case one must conclude that the locus of visual extrapolation precedes that of crowding reinforcing the idea that the visual system deals relatively early with the problem of providing a continuity to objects that disappear behind other objects. Our findings support this hypothesis, revealing that indeed, the visual system maintains more than just positional information for disappearing objects. Notably, we discovered that the features of disappearing objects can influence visible targets differently based on the colors of surrounding flankers. Additionally, these object features can persist in visual memory for surprisingly long durations, more than 400ms, even with brief presentations as short as 100 milliseconds.

Moreover, we observed that the region where the features of disappeared objects linger doesn't strictly follow their spatiotemporal trajectory but instead encompasses a broader area around the occluders. In essence, our research underscores that temporarily vanished objects remain active in brain processes and can bias current perception. While the mechanism lacks the ability to extrapolate object dynamics across space and time, it does impact any object in proximity to the occluder, suggesting that the brain attributes vanished object features to emerging objects from the occluded space.