A new look at novelty effects: guiding search away from old distractors.

We examined whether search is guided to novel distractors. In Experiment 1, subjects searched for a target among one new and a variable number of old distractors. Search displays in Experiment 2 consisted of an equal number of new, old, and familiar distractors (the latter repeated occasionally). We found that eye movements were preferentially directed to a new distractor on target-absent trials and that subjects tended to immediately fixate a new distractor after leaving the target on target-present trials. In both cases, first fixations on old distractors were consistently less frequent than could be explained by chance. We interpret these patterns as evidence for negative guidance: Subjects learn the visual features associated with the set of old distractors and then guide their search away from these features, ultimately resulting in the preferential fixation of novel distractors.