Focused attention in the perception and retrieval of multidimensional stimuli

This paper reports some further experiments on successive matching of multidimensional stimuli in which the correct conjunctions of features must be specified; it also modifies and extends the model proposed earlier by Treisman, Sykes, and Gelade (1977). The results obtained in the previous experiment were replicated despite a change from fixed to varied targets, and from spatial to temporal separation of the targets, thus extending their generality. The modified conjunction-matching model proposes that the subject progressively narrows his focus of attention, first to deal with a single display stimulus at a time and finally, if necessary, to a single target. The model was tested quantitatively by simulating the separate stages hypothesized to underlie conjunction-matching in some simpler, single-attribute-matching conditions, and using the differences between latencies in these conditions to predict differences between latencies in the appropriate conjunction-matching conditions. The results were consistent with the general hypothesis that one important role of focused attention and serial processing is to integrate separable attributes or features into the correct conjunctions, which correspond to the objects actually presented or stored.