Has feature integration theory come unglued? A reply to Tsal.

Abstract

Tsal (1989) presented a critical review of feature integration theory (FIT) and of a number of studies that have purported to show a direct relationship between focal attention and the perception of illusory conjunctions. Conceptual difficulties with the theory are highlighted, and Tsal concluded that the reviewed studies have not provided sufficient empirical support. We argue that neither Tsal's conceptual criticism nor his empirical ones are convincing enough to warrant rejection of FIT and that he has not suggested an obvious and unique theoretical alternative that inspires an appropriate empirical test. A problem for FIT that Tsal did not raise is discussed. That is, the visual primitives assumed by the theory are not clearly specified or related to known neurophysiological or psychophysical evidence concerning early vision. Nevertheless, we conclude that HT remains a viable theoretical framework. Treisman's feature integration theory (FIT) proposes that illusory conjunctions can occur if attention is diverted from a display of several figures (Treisman & Schmidt, 1982). Converging evidence from a wide variety of paradigms has supported the theory (e.g., Treisman, 1985; Treisman & Gelade, 1980; Treisman & Schmidt, 1982). Tsal (1989) critiqued four studies that purport to show a direct relationship between attention and illusory conjunctions and argued that the lack of empirical support for FIT, combined with conceptual difficulties the model faces, renders its major claims unsupported. In this article we hope to demonstrate that none of his attacks on FIT can be sustained and that despite some ambiguity FIT remains a viable framework.