A new hypothesis about the role of focused attention is proposed. The feature-integration theory of attention suggests that attention must be directed serially to each stimulus in a display whenever conjunctions of more than one separable feature are needed to characterize or distinguish the possible objects presented. A number of predictions were tested in a variety of paradigms includ- ing visual search, texture segregation, identification and localization, and using both separable dimensions (shape and color) and local elements or parts of figures (lines, curves, etc. in letters) as the features to be integrated into complex wholes. The results were in general consistent with the hypothesis. They offer a new set of criteria for distinguishing separable from integral features and a new rationale for predicting which tasks will show attention limits and which will not. When we open our eyes on a familiar scene, we form an immediate impression of recognizable objects, organized coherently in a spatial framework. Analysis of our experience into more elementary sensations is difficult, and appears subjectively to require an unusual type of per- ceptual activity. In contrast, the physiological evidence suggests that the visual scene is analyzed at an early stage by specialized populations of receptors that respond selectively to such properties as orientation, color, spatial frequency, or movement, and map these properties in different areas of the brain (Zeki, 1976). The controversy between analytic and synthetic theories of perception goes back many years: the As- sociationists asserted that the experience of complex wholes is built by combining more elementary sensations, while the Gestalt psychologists claimed that the whole precedes its parts, that we initially register unitary objects and relationships, and only later, if necessary, analyze these ob- jects into their component parts or properties. This view is still active now (e.g., Monahan & Lockhead, 1977; Neisser, 1976). The Gestalt belief surely conforms to the normal subjective experience
Published in 1980.