Directed Visual Attention and the Dynamic Control of Information Flow

Visual attention is a process that directs a tiny fraction of the information arriving at primary visual cortex to high-level centers involved in visual working memory and pattern recognition. The chapter discusses a framework for modeling this mechanism in that information flow through the visual hierarchy is regulated by dynamic control of connectivity. A key aspect of this model involves the establishment of an object-centered reference frame for visual working memory as well as object recognition. Psychophysical evidence suggests that the size of the reference frame, or region of interest, has a fixed width of about 30 resolution elements. This model is neuro-biologically plausible, supported by several lines of anatomical and physiological data, and suitable for embedding into a larger computational framework for modeling of neural representations and transformations.