Task Switching Does Not Change The Efficiency Of Feature Search

This study investigated whether or not the reconfiguration of set task could modulate the efficiency of feature search. In Experiment 1, the target-set size was manipulated. The results revealed that enumerating targets defined by color yields a much steeper slope when executed simultaneously with a discrimination task than when done singly. However, when the distractor-set size was manipulated, there was no significant difference in the efficiency of individualizing targets from distractors between the two task conditions, no matter whether the search was guided by bottom-up information (Experiment 2) or top-down information (Experiment 3). In Experiment 4, by directly estimating the search slope of the feature search task adopted in Experiment 3, further evidence against dynamic control theory was obtained.Drawing upon these results, the authors propose that (1) an additional task can impair the efficiency of enumeration, resulting in a steep slope of counting even when the target-set size is quite small; (2) in feature search, the visual system first reconfigures the task set to match the input feature information, then detects the targets with an optimal efficiency.