Abstract

The long term aim is to combine basic and applied research so as to apply psychophysical and evoked potential techniques and the results of modern vision research to the mechanisms of visual pathway diseases and to improving diagnostic and monitoring procedures.
Specific aims are as follows: (1) Multiple sclerosis and optic neuritis. Use psychophysical and evoked potential measures of spatial discrimination, spatial frequency and orientation bandwidth, and contrast sensitivity to further define organically-caused distortions of spatial vision. Differentiate the contributions of ON and OFF channel abnormality to overall visual loss. Relate these visual abnormalities to findings on the functional organization of central visual pathways in nonhuman primate. Compare different methods for monitoring the progress of visual demyelination. Distinguish between gaze disorder and neural processing disorder as contributors to Snellen acuity loss. (2) Amblyopia. Develop and apply a technique for measuring and monitoring binocular interactions in patients with depressed acuity due to amblyopia and retrobulbar neuritis. (3) Diabetes. Find whether a simple low-contrast test can detect early retinal changes associated with diabetes.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY007569-03
Application #
3264589
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1988-06-01
Project End
1991-05-31
Budget Start
1990-06-01
Budget End
1991-05-31
Support Year
3
Fiscal Year
1990
Total Cost
Indirect Cost

  Institution

Name
University of Toronto
Department
Type
DUNS #
259999779
City
Toronto
State
ON
Country
Canada
Zip Code
M5 1-S8

  Publications

Giaschi, D; Lang, A; Regan, D (1997) Reversible dissociation of sensitivity to dynamic stimuli in Parkinson's disease: is magnocellular function essential to reading motion-defined letters? Vision Res 37:3531-4
Giaschi, D; Regan, D (1997) Development of motion-defined figure-ground segregation in preschool and older children, using a letter-identification task. Optom Vis Sci 74:761-7
Giaschi, D E; Trope, G E; Kothe, A C et al. (1996) Loss of sensitivity to motion-defined form in patients with primary open-angle glaucoma and ocular hypertension. J Opt Soc Am A Opt Image Sci Vis 13:707-15
Regan, D; He, P (1995) Magnetic and electrical responses of the human brain to texture-defined form and to textons. J Neurophysiol 74:1167-78
Regan, D; Simpson, T (1995) Multiple sclerosis can cause visual processing deficits specific to texture-defined form. Neurology 45:809-15
Giaschi, D E; Regan, D; Kraft, S P et al. (1993) Crowding and contrast in amblyopia. Optom Vis Sci 70:192-7
Giaschi, D E; Regan, D; Kraft, S P et al. (1992) Defective processing of motion-defined form in the fellow eye of patients with unilateral amblyopia. Invest Ophthalmol Vis Sci 33:2483-9
Giaschi, D; Regan, D; Kothe, A et al. (1992) Motion-defined letter detection and recognition in patients with multiple sclerosis. Ann Neurol 31:621-8
Regan, D; Giaschi, D; Sharpe, J A et al. (1992) Visual processing of motion-defined form: selective failure in patients with parietotemporal lesions. J Neurosci 12:2198-210
Regan, D; Giaschi, D E; Kraft, S P et al. (1992) Method for identifying amblyopes whose reduced line acuity is caused by defective selection and/or control of gaze. Ophthalmic Physiol Opt 12:425-32

Showing the most recent 10 out of 11 publications