Tsion A. Eshetu¹ (), Brad T. Stilwell¹; ¹Wake Forest University

Sometimes salient stimuli, like a uniquely colored object or flashing neon sign, capture our attention, but other times they are suppressed. Recent evidence suggests that people learn to suppress salient, color singleton distractors via skill-based learning. Though the question remains, how do people achieve this learned distractor suppression, mechanistically? Previous investigations into this question have been limited by end-of-trial metrics such as response times. Here, we use eye tracking to examine the real-time dynamics of learned distractor suppression. To test these dynamics, undergraduate student participants searched for a unique target shape (e.g., a circle) among homogenous nontarget shapes (e.g., diamonds) in the additional singleton paradigm. On half of all trials, one nontarget item was rendered in a unique color, forming a color singleton distractor. Critically, when this singleton distractor was present, it appeared more often in one color than any other color, forming two conditions of distractor frequency (i.e., high versus low). To measure learned distractor suppression, we recorded eye movements, specifically, the destination of first saccades and their duration (i.e., dwell times). This combination of “where” and “for how long” participants directed their gaze allowed us to test three mechanisms. The first, the look-away hypothesis, predicts fewer fixations toward the high- than low-frequency distractors. The second, the rapid disengagement hypothesis, predicts shorter dwell times on the high- than low-frequency distractors. The third, learned oculomotor avoidance hypothesis, predicts the combination of both: fewer first fixations and shorter dwell times on the high- than low-frequency distractors. Consistent with the learned oculomotor avoidance hypothesis, participants were both less likely to direct their initial eye movements toward, and faster to disengage from, the high- than low-frequency distractors. These findings of learned oculomotor avoidance, suggest that when people suppress salient distractors, they do so through skill-based learning of oculomotor control.