Exploring the breadth of the top-down representations that control attentional disengagement.

Overview

Recent studies attribute top-down control as the primary determinant of the speed with which attention can be disengaged from an object, and disengagement has received increased interest as a means to distinguish between top-down and bottom-up accounts of attention capture. We present the results of three experiments exploring the breadth of the representations that delay attentional disengagement based on top-down goals. Experiments 1 and 2 examined whether objects similar to an observers' search target, but differing in luminance and hue, delayed the reallocation of attention in a search paradigm designed to isolate disengagement time. Experiment 3 explored whether the representations that delay disengagement are based on absolute similarity with the search target, or are tuned based on target/nontarget relationships. These three studies confirmed the role of top-down goals in automatically contributing to dwell times and revealed that the representations that underlie disengagement effects are broad (automatically delaying disengagement for items similar, but not identical to, the search target). In some cases, attention sets appeared to be graded in nature, but in others target-distractor relationships influenced the degree to which an irrelevant item held attention. Implications for theories of attention capture and potential functional significance of these automatic effects are discussed.