Unified Theories of Cognition: Attention

Attend is the operator that brings cognition to focus on the stimulus element. The duration associated with attend has several functionally necessary components. For voluntary attention, there may be a delay prior to selection of attend, measured from when the stimulus is available in working memory. Such a delay would be absent for an interruption. There must be a search for the stimulus elements, though this is likely to require an essentially fixed duration, since all of the usual problems associated with search (choice of directions, rejection of candidates, and the like) occur at the level of the decision cycle. It is important to note that preparation may be possible so that attend need not occur at all. The system must already be located at the place where the stimulus element will arrive, and must expect it there. Note that attend is not an eye-movement operation.