ABSTRACT: This clasroom demonstration explores attention in a novel visual-search task. It is a replication of classic visual search experiments that clarify the role of visual features and the conjunction of features in search (e.g., Treisman & Gelade, 1980). In these tasks, subjects typically search a visual scene for a particular target and to respond as quickly as they can when the target is detected or when they determine the target is absent from the scene.
Visual search is typically divided into two types: those that require attention and effort and those that are automatic and effortless. When a search is automatic, the target item pops-out and the participant identifies the target almost immediately. The reaction times for pop-out tasks doesn't change much with the number of distractors. During effortful searches, the reaction time to detect the target increase the more distractors there are in the scene. The target doesn't pop-out and subjects might have to search through every item in the display before they make a decision. Generally, the more similar the distractors are to the target, the more effortful the search. In many experiments, the target is defined by multiple features (e.g., color and shape). This "conjunction of features" search is effortful when the set of disctractors is comprised of different combinations of features that are similar to the target.
In this novel variation of classic visual search tasks, the target is a woman wearing green pants and an orange shirt. In the automatic condition, the distractors are always women in purple. These trials are easy because the target pops out of the background distractors. In the effortful condition, the distractors are composed of women with green shirts and orange pants. Because some of the distractors are similar, the target no longer pops out. This classroom demo is the beginnings of an experiment of visual search in 3-D virtual worlds. As virtual reality technology becomes more affordable and accessible, understanding how classic visual search occurs in VR will be important.