Abstract
Visual decisions are serially dependent and biased towards prior stimuli. It has been proposed that this bias results from mechanisms that support the continuity of object representation. Several studies suggest that these mechanisms combine prior and present stimuli depending on their proximity in retinal locations. However, it remains unclear whether the reference frame of serial dependence is truly retinotopic or allocentric and to what degree it is object-based. Here we pit the roles of object-based processing, spatial distance, and hemifield against each other. We used a well-known paradigm in which object-based attention is manipulated by presenting stimuli inside two rectangles, perceived as different objects (Egly, Driver & Rafal, 1994). On separate blocks, the rectangles were either vertical or horizontal, and we presented Gabor patches in one of the four possible ends of the rectangles, equidistant from the fovea. Participants were asked to reproduce the orientation of each Gabor. Our initial results indicate that serial dependence —the reproduction error toward the previous orientation, decreased as a function of the spatial distance, without a clear effect of presenting the stimulus on the same or a different object. Crucially, our preliminary data suggest an interaction between object processing and hemifield that might further clarify the role of attention and the reference frame of serial dependence.