Example stimuli and behavioral results from experiment 3. The visual search task in experiment 3 was the same as in task 3 of experiment 1, except that it contained two visual attention demand conditions. Visual attention demand was manipulated by varying the similarity of the visual target and nontargets. The response-target circle was red in the low demand condition (A) and dark gray in the high demand condition (B). Tones were simultaneously presented with each visual stimulus. Mean values for d-prime (C) and reaction times (D) are plotted for low demand and high demand conditions. Individual data are plotted and connected with lines to illustrate the change in performance for each participant between low and high demand conditions.