i This grant had three specific aims. I. !'~J~I: Transcending the serial/parallel dichotomy in visual search: Guided Search, our model of human visual search behavior, has n)t.QP9~(:,d that "preattentive" visual processes guide the deployment of attention from item to item in a serial, item-by-item fashion. ' i~~~~ve proposed parallel models of search. Our new model, Guided Search 4.0 and our data attempt to reconcile these views. It is .~}h5,rbrid model in which a serial bottleneck governs

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... ction of some visual objects for further processing. Visual processing before ; : '!'l.ldafter the bottleneck can be characterized as parallel. AIM 2: Understanding the role of memory in visual search: We have found visual search for targets proceeds without memory for rejected non-targets. This claim runs counter to the "common sense" observation that we direct real-world search strategically. "I have looked there. Now I will look here." New work replicates our findings and shows that the common-sense, memory processes are quite slow and, thus, often not useful in laboratory search tasks. AIM 3: The relationship of different modes of attentional control. Finally, we report on a series of experiments that show how visual search can occur at the same time as other visual tasks.