Rods progressively escape saturation to drive visual responses in daylight conditions.

ABSTRACT: Rod and cone photoreceptors support vision across large light intensity ranges. Rods, active under dim illumination, are thought to saturate at higher (photopic) irradiances. The extent of rod saturation is not well defined; some studies report rod activity well into the photopic range. Using electrophysiological recordings from retina and dorsal lateral geniculate nucleus of cone-deficient and visually intact mice, we describe stimulus and physiological factors that influence photopic rod-driven responses. We find that rod contrast sensitivity is initially strongly reduced at high irradiances, but progressively recovers to allow responses to moderate contrast stimuli. Surprisingly, rods recover faster at higher light levels. A model of rod phototransduction suggests that phototransduction

SUBMITTER: Tikidji-Hamburyan A 

PROVIDER: S-EPMC5703729 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature