This project will investigate a fundamental aspect of human perception, the ability to organize the visual world into figures and backgrounds. In everyday visual scenes, objects overlap and occlude one another, which necessitates a visual process for determining which objects lie in the foreground (figures) and which lie in the background. Psychologists have proposed a set of rules that describe figure-ground segregation. For example, a symmetrical region is more likely to be perceived as a figure than as the background. However, this descriptive approach does not specify the mechanisms of figure-ground segregation-the precise computations that allow these rules to be instantiated. Neurophysiological studies in nonhuman primates, in contrast, show promise for elucidating the mechanisms of figure-ground segregation, but the results of these studies are difficult to link with studies of human perception. The goal of this project is to bridge the gap between human perception and monkey neuro-physiology in figure-ground segregation by using noninvasive electro-physiological recordings of the brain's activity (colloquially known as 'brain waves' and technically as 'event-related potentials'). These recordings will allow us to assess the time course and neuroanatomical substrates of figure-ground segregation, thereby elucidating both the cognitive and neural mechanisms of figure-ground segregation. We hypothesize that figure-ground segregation relies on a mechanism that amplifies the neural representation of a figure relative to the neural representation of the ground. Our research uses non-invasive electro-physiological methods that can test this hypothesis more directly by measuring the sensory processes associated with both "figures" and "grounds." This research will provide an understanding of how the brain processes complex visual scenes, which may have implications for artificial vision systems and techniques for rehabilitation of visual perception following brain injury.

Agency
National Science Foundation (NSF)
Institute
Division of Behavioral and Cognitive Sciences (BCS)
Application #
9910727
Program Officer
Guy Van Orden
Project Start
Project End
Budget Start
2000-07-15
Budget End
2004-06-30
Support Year
Fiscal Year
1999
Total Cost
$182,000
Indirect Cost
Name
University of Iowa
Department
Type
DUNS #
City
Iowa City
State
IA
Country
United States
Zip Code
52242