Abstract
Serial dependence in perception describes when visual stimuli appear more similar to recently-attended stimuli than they truly are. By smoothing perception over the ever-changing image on the retina, this bias is thought to stabilize our visual experience from one moment to the next. Although this perceptual continuity is generally helpful, it fundamentally reflects a misapprehension of the current stimulus, and could therefore interfere with processing when the previous information is no longer relevant to current goals (i.e., proactive interference). If serial dependence between successive perceptual instances were flexible and adaptive, therefore, it should be reduced when environmental cues trigger the segmentation of visual episodes. Event boundaries (i.e., transitions to a new episode or context) are thought to update one's goal state in working memory, and may thereby signal that the upcoming information should be segregated from what came before. Accordingly, we expect a stable context to promote serial dependence in perception, whereas a context shift should flush the lingering trace of recent perception from memory, and curtail its influence on current processing. We tested this hypothesis by periodically changing the background color (i.e., context) during a continuous series of orientation judgments. On each trial, participants saw a randomly-oriented grating, then adjusted a response bar to match their perceived orientation of the stimulus. Across all trials, orientation responses were attracted toward the orientation from the previous trial. On the first trial in a new context, however, this serial dependence was eliminated, suggesting that the (typically attractive) previous trial information was purged at the start of a new visual episode. In contrast, all subsequent trials in a given context showed significant serial dependence. These data suggest that context transitions can update goal settings to dampen the bias toward recently-attended stimuli when it may no longer serve current goals.
Meeting abstract presented at VSS 2017