The Focus of Visuospatial Attention is Governed by Separate Processes.

Peter Squire

Advisor: Raja Parasuraman

Committee Members: Pamela Greenwood,Thomas Scruggs

David J. King Hall, 2072
April 26, 2009, 08:00 PM to 07:00 PM

Abstract:

When driving, a person’s ability to alter the location, size, and shape of where attention is directed is important for performing routine driving maneuvers and for identifying potential hazards. Visuospatial attention is a "malleable, movable resource that can heighten processing within regions of space where it is directed" (Greenwood & Parasuraman, 2004, p. 3).  Research has shown that the orienting—moving from one location to another—and distributing—altering the size and shape across visual space—of visuospatial attention can be driven by a conscious voluntary process or captured by a reflexive involuntary process.  While numerous studies have examined these various forms or manifestations of visuospatial attention, it is not clear if a unified process or separate processes govern visuospatial attention. The current dissertation systematically explores the question of whether a unified process or separate processes govern visuospatial attention. Four experiments were performed, using a visual search task paradigm to investigate the question of the unified process or separate processes. Findings based on search accuracy suggest that visuospatial attention is governed by separate processes, specifically an involuntary process and a voluntary process that direct orienting and distributing of visuospatial attention.