9222324 KORNBLUM These studies are part of a broad, ongoing research program on the basic, elemental, cognitive processes involved in the performance of simple and complex tasks. In this research, the focus will be on a family of eight classic experimental paradigms in cognitive psychology. According to the taxonomy derived from Kornblum's recently published model, the dimensional overlap model, these paradigms are all variants of either stimulus-stimulus and/or stimulus-response compatibility. Fundamental problems come to light in the course of attempting to identify the processing mechanisms that mediate the facilitation and interference effects observed in performance with those tasks. According to the model, these effects are consequences of the dimensional overlap (i.e., the similarity) between the sets of stimuli and responses, and/or the relevant and irrelevant aspects of these tasks. The experiments will test specific predictions of the model. In particular, the first experiment will test the model's predictions concerning the effects of irrelevant dimensions in four related paradigmatic tasks, while the second experiment will seek to identify the limits within which the model applies in single response tasks. The results will not only contribute to our understanding of the cognitive and attentional processes involved in performance, but will enable us to assess the consequences of varying work load in these and other similar tasks. ***
