How we learn to ignore singleton distractors: Suppressing saliency signals or specific features?

Salient visual information can sometimes capture attention despite our goals. However, there are several ways we can minimize or eliminate such distraction. One such way is learned distractor rejection, in which we increasingly ignore salient, irrelevant distractors across repeated exposures. Here, we probe the mechanism underlying this learned rejection. What must be learned about the distractor to promote effective ignoring? Specifically, is feature rejection, alone, sufficient to ignore salient distractors, or do the items' saliency signals need to also be rejected? We used a modified version of the learned distractor rejection paradigm (Vatterott & Vecera, 2012) in which participants viewed training blocks containing either a salient singleton distractor or three non-salient "tripleton" distractors, followed by test blocks in which the distractor shared a feature (color) with the corresponding training blocks, but was always salient. Results revealed unexpected difficulties in replicating learned distractor rejection, suggesting the true effect size may be smaller than initially reported. With respect to our main objective, we found similar attenuation of singleton presence costs in the test blocks regardless of whether they followed singleton or tripleton training blocks. These results show that experience in rejecting saliency signals is not a requirement of learned distractor rejection.