Fig. 1.

a Sequence of events and time course of a trial in the visual search task. On each trial, an exact cue of the upcoming conjunction target defined by a combination of a specific color and orientation was presented, and participants pressed one of two keys to indicate whether the target was present or absent in the search display. In this specific example, the target was a green 50° tilted grating. b Example search displays for different trial types in Experiment 1. The distractor items were all identical, enabling pop-out search. In color trials, distractors had the same orientation but different color with the target. In orientation trials, distractors had the same color, but different orientation with the target. The half of each trial type contained the target in the search display (target present) and the other half did not (target absent). The percentage of color and orientation trials was manipulated across distractor contexts: The color-weighted distractor context consisted of 80% color trials and 20% orientation trials, whereas the orientation-weighted distractor context consisted of 20% color trials and 80% orientation trials. (Color figure online)