title: Blue-yellow opponency in primate S cone photoreceptors.
abstract: The neural coding of human color vision begins in the retina. The outputs of long (L)-, middle (M)-, and short (S)-wavelength-sensitive cone photoreceptors combine antagonistically to produce "red-green" and "blue-yellow" spectrally opponent signals (Hering, 1878; Hurvich and Jameson, 1957). Spectral opponency is well established in primate retinal ganglion cells (Reid and Shapley, 1992; Dacey and Lee, 1994; Dacey et al., 1996), but the retinal circuitry creating the opponency remains uncertain. Here we find, from whole-cell recordings of photoreceptors in macaque monkey, that "blue-yellow" opponency is already present in the center-surround receptive fields of S cones. The inward current evoked by blue light derives from phototransduction within the outer segment of the S cone. The outward current evoked by yellow light is caused by feedback from horizontal cells that are driven by surrounding L and M cones. Stimulation of the surround modulates calcium conductance in the center S cone.
authors.affiliation: Department of Biological Structure and the National Primate Research Center, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Orin S
authors.initials: OS
authors.lastname: Packer
authors.forename: Jan
authors.initials: J
authors.lastname: Verweij
authors.forename: Peter H
authors.initials: PH
authors.lastname: Li
authors.forename: Julie L
authors.initials: JL
authors.lastname: Schnapf
authors.forename: Dennis M
authors.initials: DM
authors.lastname: Dacey
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D001676:Biofeedback, Psychology / Q000502:physiology; D001703:Biophysics; D002118:Calcium / Q000378:metabolism; D003116:Color; D003118:Color Perception / Q000502:physiology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D008027:Light; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009433:Neural Inhibition / Q000187:drug effects; D018408:Patch-Clamp Techniques / Q000379:methods; D010775:Photic Stimulation / Q000379:methods; D026902:Potassium Channel Blockers / Q000494:pharmacology; D011323:Primates / Q000033:anatomy & histology; D012160:Retina / Q000166:cytology*; D017949:Retinal Cone Photoreceptor Cells / Q000145:classification / Q000502:physiology*; D019789:Tetraethylammonium / Q000494:pharmacology; D014794:Visual Fields / Q000502:physiology
chemical_list: D018691:Excitatory Amino Acid Antagonists; D026902:Potassium Channel Blockers; D019789:Tetraethylammonium; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D002118:Calcium