Resolution acuity across the visual field for mesopic and scotopic illumination.

ABSTRACT: We investigated the classical question of why visual acuity decreases with decreasing retinal illuminance by holding retinal eccentricity fixed while illumination varied. Our results indicate that acuity is largely independent of illuminance at any given retinal location, which suggests that under classical free-viewing conditions acuity improves as illumination increases from rod threshold to rod saturation because the retinal location of the stimulus is permitted to migrate from a peripheral location of maximum sensitivity but poor acuity to the foveal location of maximum acuity but poor sensitivity. Comparison with anatomical sampling density of retinal neurons suggests that mesopic acuity at all eccentricities and scotopic acuity for eccentricities beyond about 20° is limited by the sp

SUBMITTER: Wilkinson MO 

PROVIDER: S-EPMC7545082 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature