Processing of S-cone signals in the inner plexiform layer of the mammalian retina

Vis Neurosci. 2014 Mar;31(2):153-63. doi: 10.1017/S0952523813000308. Epub 2013 Sep 9.


Color information is encoded by two parallel pathways in the mammalian retina. One pathway compares signals from long- and middle-wavelength sensitive cones and generates red-green opponency. The other compares signals from short- and middle-/long-wavelength sensitive cones and generates blue-green (yellow) opponency. Whereas both pathways operate in trichromatic primates (including humans), the fundamental, phylogenetically ancient color mechanism shared among most mammals is blue-green opponency. In this review, we summarize the current understanding of how signals from short-wavelength sensitive cones are processed in the primate and nonprimate mammalian retina, with a focus on the inner plexiform layer where bipolar, amacrine, and ganglion cell processes interact to facilitate the generation of blue-green opponency.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amacrine Cells / physiology
  • Animals
  • Color Vision / physiology*
  • Cone Opsins / metabolism
  • Humans
  • Mammals
  • Primates
  • Retinal Bipolar Cells / physiology
  • Retinal Cone Photoreceptor Cells / physiology*
  • Retinal Ganglion Cells / physiology
  • Retinal Neurons / physiology*
  • Visual Pathways / physiology*


  • Cone Opsins