Mechanisms of the associated nontargets effect: Processes influenced by statistical learning in a simple visual environment

Abstract

In three visual search experiments participants were asked to make a target response if either of two targets was present and to make a nontarget response if neither target was present. Some target-absent displays included only nontarget features that never occurred in the same displays as target features, whereas other target-absent displays included nontarget features that did sometimes occur with target features. Nontarget responses were reliably faster in the former case than in the latter. This “associated nontargets effect” appears to arise from participants' ability to learn and to use contingencies between the presence of certain nontargets and the absence of any target.

The authors would like to thank Axel Buchner, Joseph Krummenacher, and an anonymous reviewer for helpful comments on an earlier version of this paper.

Notes

¹As described in the guided search model of visual search (Wolfe, 1994, 1996; Wolfe, Cave, & Franzel, 1989), activation maps provide one mechanism by which such associations between a target and nontargets could facilitate visual search.

²In all analyses reported in the present paper, the Geisser–Greenhouse correction was used to counter possible violations of sphericity.

³Redundant targets were not included in order to simplify the construction of the stimulus set and to concentrate experimental trials in the conditions of interest as much as possible.

⁴In Experiments 1 and 3 of the present paper the questionnaires used were generated in tandem with the generation of the stimulus sets and therefore were different for each participant. This was not the case in Experiment 2, which used the same questionnaire for all participants.

⁵For all target-absent trials in the SOA = 500 blocks, RT was measured from the presentation of the second feature. For target-present trials in the SOA = 500 blocks, RT was measured from the presentation of a target feature.