Response cost to repeated displays--when previous distractors become targets.

Abstract

A varied-target search task was used to evaluate the response cost of previous distractors becoming current targets in repeated visual search. We compared the relative contributions of distractor identity and location to producing response cost. During an exposure phase, half of the items were possible targets in each repeated display, and the other half were always distractors. Participants searched for a different target from the set of potential targets when the search displays were repeated. In the test phase of Experiments 1a and 1b, the roles of targets and distractors were reversed while the overall configuration was unchanged. Results indicated significant contextual costs after the switch of identities/locations between distractors and targets. In the test phase of Experiments 2a and 2b, target identities were changed again but the target locations remained the same. Less response cost was observed in this condition relative to when both identities and locations were changed. Proximity between target and distractors in the repeated displays also influenced response cost. The mechanisms responsible for the various response cost effects and the interplay between identity, location, and proximity in the production of response cost were discussed.