Important issues fade into the background for a while, only to reappear when a new generation takes them up. In this paper, we present our most recent work on visual search. Enoch had subjects search for targets in aerial photographs and found that Ss were biased to search the center of the image. Understanding visual search in natural images of this sort has proven to be a difficult topic. Most of the progress in the last generation has been made with more easily analyzed but less realistic stimuli.
Different tasks produce characteristically different results.
RT is roughly independent of set size. Adding more horizontal lines does not slow search. He distinguished between preattentive processes that could perform simple tasks across the entire visual field in parallel and attentive processes that perform more complex tasks only in a limited area at one time. It held that preattentive feature processes could perform feature searches in parallel, while attention from item to item was required to do all other searches. The basic idea is shown in Figure 2.