Behavioral Differences in the Upper and Lower Visual Hemifields in Shape and Motion Perception.

Perceptual accuracy is known to be influenced by stimuli location within the visual field. In particular, it seems to be enhanced in the lower visual hemifield (VH) for motion and space processing, and in the upper VH for object and face processing. The origins of such asymmetries are attributed to attentional biases across the visual field, and in the functional organization of the visual system. In this article, we tested content-dependent perceptual asymmetries in different regions of the visual field. Twenty-five healthy volunteers participated in this study. They performed three visual tests involving perception of shapes, orientation and motion, in the four quadrants of the visual field. The results of the visual tests showed that perceptual accuracy was better in the lower than in the upper visual field for motion perception, and better in the upper than in the lower visual field for shape perception. Orientation perception did not show any vertical bias. No difference was found when comparing right and left VHs. The functional organization of the visual system seems to indicate that the dorsal and the ventral visual streams, responsible for motion and shape perception, respectively, show a bias for the lower and upper VHs, respectively. Such a bias depends on the content of the visual information.

Our future selves : a research plan toward understanding aging : summary reports /

Mode of access: Internet.

Our future selves : a research plan toward understanding aging : report /

Mode of access: Internet.

The changing climate in accident research.

Mode of access: Internet.

Effects of price changes on automobile driving: an exploration of alternative behavioral assumptions.

Mode of access: Internet.

Exploration in responsible business behavior: an exercise in behavioral economics.

Cover title.

List of U.S. Army Research Institute research and technical publications : October 1, 1990, to September 30, 1991 with author and subject index.

Mode of access: Internet.

Fundamental research and the process of education : final report to the National Institute of Education /

Mode of access: Internet.

List of U.S. Army Research Institute research and technical publications.

Description based on: Oct. 1, 1989-Sept. 30, 1990 issue.

Behavioral pharmacology of human drug dependence /

Mode of access: Internet.

The ARI "product book" : recent achievements in soldier-oriented research and development.

Mode of access: Internet.

List of U.S. Army Research Institute research and technical publications : October 1, 1989 to September 30, 1994 : with author and subject index /

Mode of access: Internet.

Determinants of effective unit performance : research on measuring and managing unit training readiness /

Mode of access: Internet.

List of research publications, 1940-1980 /

"October 1981."

Behavioral therapies for urinary incontinence in aged female nursing home residents /

Research conducted by the University of Illinois College of Nursing.