Shinhae Ahn¹ (), Richard A. Abrams¹; ¹Washington University in St. Louis

For successful goal-directed actions, it is crucial to prioritize relevant information while filtering out salient-but-irrelevant distractors to guide accurate movements toward a target. Previous studies have shown that when perceptual salience is manipulated by color contrast between a distractor and other items, highly salient distractors can be proactively suppressed more strongly than less salient ones under top-down control, as evidenced by reduced oculomotor capture. However, little is known about how the perceptual salience of distractors modulates the spatiotemporal dynamics of attentional suppression during reaching. The present study investigated the mechanisms underlying the strong suppression of highly salient distractors and examined how these mechanisms differ from those involved in suppressing less salient distractors by analyzing reaching movement trajectories. Participants made rapid mouse-reaching movements to a target in the presence of distractors in two experiments. Distractor salience was manipulated by: (1) varying the color contrast between the distractor and other items (highly salient vs. less salient colors), and (2) varying color-fill status, where search items appeared as fully colored shapes or as colored outlines (filled vs. unfilled shapes). Across both experiments, stronger distractor salience led to greater distractor-presence benefits, with suppression of high color-contrast distractors benefiting movement onset latencies and suppression of filled shapes benefiting movement durations. Interestingly, reaching movement trajectories revealed repulsion away from highly salient distractors, whereas less salient distractors elicited reduced repulsion or even attraction toward the distractors. Overall, the findings show that both the type and magnitude of distractor salience distinctively modulate suppression mechanisms, exhibiting specific spatiotemporal dynamics during reaching movements.