Abstract
Recent studies have shown that past experiences with salient distractors lead to better suppression. However, there is disagreement over how deeply the salient distractor is processed. In this study, we directly measured memory for a salient distractor with a surprise memory trial. Two groups, SingletonTrained (N=320) and Control (N=320), were asked to find a shape singleton among five identically shaped distractors. All stimuli were gray in color. The SingletonTrained group saw a color singleton on 80% of trials; the Control group saw only one color singleton trial. Both groups unexpectedly encountered a “surprise memory trial” at some point where they were asked 1) whether the preceding search display contained a color singleton; 2) how confident they were in their response; 3) the color of the singleton; 4) where the color singleton was located. Critically, eight sub-groups (N=40 each) experienced the memory trial at different time points in the experiment (e.g., in the SingletonTrained group following the first singleton vs. the 24th singleton; in the Control group, following the only singleton occurring on the first vs. the 24th trial). Subjects that saw more color singleton trials before the memory trial showed stronger suppression (ie., less RT interference), reported seeing the color singleton less often, had lower confidence in their reports, and also showed poorer memory for the color and location of the color singleton than the Control group. This pattern was also seen at the individual level such that subjects with stronger attentional capture by the color singleton also had a better memory of its color and location. Together these findings suggest that learned suppression of attention to salient distractors leads to less search interference and less precise memories of the distractor.