About 2% of children develop a type of relative blindness in one eye known as functional amblyopia -- a deficit in central visual acuity for which no obvious optical or pathological cause can be determined. The structures of the visual system that are affected and the ways they are altered are not fully known. Treatment of functional amblyopia, no longer believed to be limited to children under 6 years, is nonetheless only partially effective for most patients. The present application requests renewal of a grant (1-R01-EY02125) that supported the successful development of an auditory - feedback technique which has now been shown to produce steady and foveal fixation of eccentrically fixating amblyopic eyes. Using this feedback technique, several fundamental questions about the sensory and motor mechanisms of amblyopia have been answered. With the proposed renewal support, sensory and motor mechanisms of vision will be investigated with the aim of testing a central hypothesis: """"""""Most, if not all of the sensory deficits (e.g., visual acuity, contrast sensitivity, spatial summation) and oculomotor abnormalities (e.g., unsteady fixation, eccentric fixation, poor smooth and saccadic tracking) are explained by the aberrated or distorted space sense present in a central retinal region of functionally amblyopic eyes."""""""" Of the eight specific aims and """"""""experiments"""""""" that stem from this hypothesis six will be performed in the laboratory and two will be conducted in a clinic setting -- the latter involve a) development of a clinically applicable battery of tests to evaluate functional amblyopia in each of its basic deficits, and b) develop clinically applicable feedback training procedures that efficiently promote steady, foveal fixation and foveal directionalization in functionally amblyopic eyes.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY003694-07
Application #
3258118
Study Section
(SSS)
Project Start
1980-08-01
Project End
1990-02-28
Budget Start
1987-03-01
Budget End
1988-02-29
Support Year
7
Fiscal Year
1987
Total Cost
Indirect Cost
Name
University of Houston
Department
Type
Schools of Optometry/Opht Tech
DUNS #
800771594
City
Houston
State
TX
Country
United States
Zip Code
77204
Klein, B E; Klein, R; Lee, K E (1998) Renal function abnormalities and incident cataract after a five-year interval: The Beaver Dam Eye Study. Curr Eye Res 17:720-5
Bedell, H E; Yap, Y L; Flom, M C (1990) Fixational drift and nasal-temporal pursuit asymmetries in strabismic amblyopes. Invest Ophthalmol Vis Sci 31:968-76
Mapp, A P; Barbeito, R; Bedell, H E et al. (1989) Visual localization of briefly presented peripheral targets. Biol Cybern 60:261-5
Barbeito, R; Bedell, H E; Flom, M C (1988) Does impaired contrast sensitivity explain the spatial uncertainty of amblyopes? Invest Ophthalmol Vis Sci 29:323-6
Barbeito, R; Bedell, H E; Flom, M C et al. (1987) Effects of luminance on the visual acuity of strabismic and anisometropic amblyopes and optically blurred normals. Vision Res 27:1543-9
Simpson, T L; Barbeito, R; Bedell, H E (1986) The effect of optical blur on visual acuity for targets of different luminances. Ophthalmic Physiol Opt 6:279-81
Bedell, H E (1986) Some constraints on peripheral visual functioning. Introduction. Am J Optom Physiol Opt 63:91-3
Flom, M C; Bedell, H E (1985) Identifying amblyopia using associated conditions, acuity, and nonacuity features. Am J Optom Physiol Opt 62:153-60
Bedell, H E; Johnson, M H; Barbeito, R (1985) Precision and accuracy of oculocentric direction for targets of different luminances. Percept Psychophys 38:135-40
Bedell, H E; Flom, M C; Barbeito, R (1985) Spatial aberrations and acuity in strabismus and amblyopia. Invest Ophthalmol Vis Sci 26:909-16

Showing the most recent 10 out of 11 publications