Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and cones

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Publication Type Journal Article
School or College School of Medicine
Department Ophthalmology; Bioengineering; Surgery; Physiology
Creator Normann, Richard A.
Other Author Werblin, Frank S.
Title Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and cones
Date 1974
Description Rods and cones in Necturus respond with graded hyperpolarization to test flashes spanning about 3.5 log units of intensity. Steady background levels hyperpolarize the rods, and the rod responses become progressively smaller as background level is increased. In cones, higher background levels reduce the effectiveness of test flashes, so higher ranges of test intensities are required to elicit the full range of graded responses. When backgrounds are terminated, cones return rapidly, but rods return slowly to the dark potential level. The effects of backgrounds on both rods and cones can be observed at intensities that cause negligible bleaching as determined by retinal densitometry. During dark adaptation, changes are observed in the rods and cones that are similar to those produced by backgrounds. Receptor sensitivities, derived from these results, show that rods saturate, cones obey Weber's law, and sensitization during dark adaptation follows a two-phase time-course.
Type Text
Publisher Rockefeller University Press
Volume 63
Issue 1
First Page 37
Last Page 61
Subject Retina;Light and Dark Adaptation; Recepters; Bipolars; Ganglion Cells
Subject MESH Retina; Electrophysiology; Photoreceptors; Synaptic Transmission
Language eng
Bibliographic Citation Normann RA, Werblin FS. (1974). Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and cones. J Gen Physiol, 63(1), 37-61
Rights Management © Rockefeller University Press
Format Medium application/pdf
Identifier ir-main,12719
ARK ark:/87278/s66t1520
Setname ir_uspace
Date Created 2012-06-13
Date Modified 2012-06-13
ID 704875
Reference URL https://collections.lib.utah.edu/ark:/87278/s66t1520
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