Melanopsin-expressing ganglion cells in primate retina signal colour and irradiance and project to the LGN

Nature. 2005 Feb 17;433(7027):749-54. doi: 10.1038/nature03387.

Abstract

Human vision starts with the activation of rod photoreceptors in dim light and short (S)-, medium (M)-, and long (L)- wavelength-sensitive cone photoreceptors in daylight. Recently a parallel, non-rod, non-cone photoreceptive pathway, arising from a population of retinal ganglion cells, was discovered in nocturnal rodents. These ganglion cells express the putative photopigment melanopsin and by signalling gross changes in light intensity serve the subconscious, 'non-image-forming' functions of circadian photoentrainment and pupil constriction. Here we show an anatomically distinct population of 'giant', melanopsin-expressing ganglion cells in the primate retina that, in addition to being intrinsically photosensitive, are strongly activated by rods and cones, and display a rare, S-Off, (L + M)-On type of colour-opponent receptive field. The intrinsic, rod and (L + M) cone-derived light responses combine in these giant cells to signal irradiance over the full dynamic range of human vision. In accordance with cone-based colour opponency, the giant cells project to the lateral geniculate nucleus, the thalamic relay to primary visual cortex. Thus, in the diurnal trichromatic primate, 'non-image-forming' and conventional 'image-forming' retinal pathways are merged, and the melanopsin-based signal might contribute to conscious visual perception.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cells, Cultured
  • Color Perception / physiology*
  • Darkness
  • Humans
  • In Vitro Techniques
  • Light
  • Light Signal Transduction / radiation effects
  • Macaca / physiology*
  • Retina / cytology
  • Retina / physiology
  • Retina / radiation effects
  • Retinal Cone Photoreceptor Cells / physiology
  • Retinal Cone Photoreceptor Cells / radiation effects
  • Retinal Ganglion Cells / cytology
  • Retinal Ganglion Cells / physiology*
  • Retinal Ganglion Cells / radiation effects
  • Retinal Rod Photoreceptor Cells / physiology
  • Retinal Rod Photoreceptor Cells / radiation effects
  • Rod Opsins / genetics
  • Rod Opsins / metabolism*
  • Thalamic Nuclei / physiology*
  • Thalamic Nuclei / radiation effects
  • Visual Pathways / physiology
  • Visual Pathways / radiation effects

Substances

  • Rod Opsins
  • melanopsin