Abstract
Judgments of the present visual world are affected by what came before. When judgements of visual properties such as orientation are biased in the direction of preceding stimuli, this is called visual serial dependence. Visual serial dependence is thought to arise from mechanisms that support perceptual continuity: because physical properties of an object usually vary smoothly in time, perception might be accurately stabilized by smoothing the perceived features in time. However, mechanisms that support perceptual continuity should be object specific, because the orientation of one object is more related to its own past than it is to the past of a distinct object. Thus, we tested the perceptual continuity explanation by comparing the magnitude of serial dependence between objects and within objects. Across three experiments, we manipulated objecthood by varying the color, the location, and both the color and the location of Gabor patches. We observed a serial dependence effect in every experiment, but did not observe an effect of objecthood in any experiment. We further observed serial dependence even when the orientations of two successive stimuli were nearly orthogonal. These data are inconsistent with explanations of serial dependence based on visual continuity. We hypothesize that serial dependence arise from a combination of perceptual features and internal response variables, which interact within a common task or decisional context.
