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Maintenance of FINSTs across eye movements

An ongoing research program . . .

By Christopher Currie and Zenon Pylyshyn

I. Introduction: Individuating and indexing
(Taken with permission from Pylyshyn's
Visual Attention Research

In the past several years, there has been much investigation into the nature of visual-indexing. The theory (so-called FINST Indexing Theory) consists of a set of hypotheses about a mechanism by which certain salient features or objects in a visual display are indexed (i.e. "FINSTed") so that they can be referred to by subsequent cognitive processes.

According to the theory an early stage in visual perception involves a resource-limited mechanism for the individuation of a small number (4-6) of visual entities (possibly perceptual objects in the sense used by Treisman and by Yantis). Specifically, a small number of tokens are selected and indexed so that: (1) subsequent stages of the visual system are able to reference the indexed tokens; (2) an index remains attached to its token as the token changes its retinal location or other properties, allowing it to be tracked, qua individual object; (3) indexed tokens can be interrogated without the necessity of first locating them through some form of search or without reference to their individual properties; and (4) only indexed tokens can be the targets of motor movements, including eye-movements, since motor programs, like visual routines, also require that their arguments to be bound to tokens. For a more detailed list of assumptions, click here.