Goal-Directed Attentional Selection: Limitations From Input Variables, Not Imprecision

When searching for a target object in a cluttered scene, the currently attended object is typically matched against a target template, a memory representation of the object being actively searched for. To determine if the currently attended item is the target requires a high degree of similarity to the template; any imprecision would make it difficult to distinguish between targets and visually similar nontargets. Thus, for attention to be efficient in finding targets requires the target template to be highly precise. Initial research on the precision of the target template suggested that the template was a highly precise depiction of the target object. In contrast, more recent findings suggested an imprecise template, demonstrating that participants were inaccurate in detecting a target when it appeared among visually similar distractors. In the current experiments, we demonstrate that visually similar distractors can hinder attentional selection because of limitations in selection and masking, not because of template imprecision. We conclude that the target template can be highly precise yet performance limited by factors not related to the target template itself.