LOOKING FOR 2 TARGETS AT THE SAME TIME - ONE SEARCH OR 2

A considerable amount of evidence suggests that, under conditions of h igh discriminability, subjects are able to process multiple elements i n a visual display simultaneously when searching for a single target a mong distractors. Relatively little emphasis, however, has been placed on the question of whether subjects can search for and detect multipl e targets simultaneously. This latter question is the focus of the pre sent report. In two experiments, we compare performance in single-targ et and multiple-target detection tasks in order to investigate whether or not multiple targets can be detected simultaneously. In Experiment 1, subjects searched for one or two targets that were defined by colo r. In Experiment 2, subjects searched for a color and/or a letter targ et. When the two targets were presented in the same location (e.g., a red X when Target 1 was red and Target 2 was an X), they seemed to be detected simultaneously. Implications for object-based processing of v isual information are discussed.