Color Vision Deficits in Intermediate Age-Related Macular Degeneration

Abstract

PURPOSE: To assess the effect of intermediate age-related macular degeneration (AMD) on foveal cone-contrast thresholds. METHODS: We measured L-M and S-cone-contrast thresholds in subjects with intermediate AMD (n = 10) and age-matched control subjects (n = 10). Monocular, foveal 3-degree Gaussian blobs (600-millisecond raised cosine) were presented at 16 cone ratios throughout L-, M-, and S-cone space, and threshold contours were modeled with probability summation between two independent detection mechanisms. The role that preretinal absorption plays in aging was also evaluated by simulation with FG15 and neutral-density filters. RESULTS: Aging results in loss of neural sensitivity, not exp..