S-cone photoreceptors in the primate retina are functionally distinct from L and M cones
Jacob Baudin,
Juan M Angueyra,
Raunak Sinha,
Fred Rieke
Affiliations
Jacob Baudin
Department of Physiology and Biophysics, University of Washington, Seattle, United States; Howard Hughes Medical Institute, University of Washington, Seattle, United States; Google Inc., Seattle, United States
Department of Physiology and Biophysics, University of Washington, Seattle, United States; Howard Hughes Medical Institute, University of Washington, Seattle, United States
Department of Physiology and Biophysics, University of Washington, Seattle, United States; Howard Hughes Medical Institute, University of Washington, Seattle, United States; Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, Madison, United States
Department of Physiology and Biophysics, University of Washington, Seattle, United States; Howard Hughes Medical Institute, University of Washington, Seattle, United States
Daylight vision starts with signals in three classes of cone photoreceptors sensitive to short (S), middle (M), and long (L) wavelengths. Psychophysical studies show that perceptual sensitivity to rapidly varying inputs differs for signals originating in S cones versus L and M cones; notably, S-cone signals appear perceptually delayed relative to L- and M-cone signals. These differences could originate in the cones themselves or in the post-cone circuitry. To determine if the cones could contribute to these and related perceptual phenomena, we compared the light responses of primate S, M, and L cones. We found that S cones generate slower light responses than L and M cones, show much smaller changes in response kinetics as background-light levels increase, and are noisier than L and M cones. It will be important to incorporate these differences into descriptions of how cone signaling shapes human visual perception.
