Feedback connections and operation of the outer plexiform layer of the retina

Curr Opin Neurobiol. 1992 Aug;2(4):462-8. doi: 10.1016/0959-4388(92)90181-j.

Abstract

The primary feedback control apparatus in the outer retina is the sign-inverting feedback synapse between horizontal cells and cones. In many lower vertebrates horizontal cells release GABA in darkness, which opens Cl- channels in cones. Input-output relations of the feedback synapse reveal that the synaptic gain is light-dependent with the highest negative gain near the dark horizontal cell potential. The horizontal cell-cone feedback synapse improves the reliability of the photoreceptor output synapses. It also modulates the dynamic range and mediates color opponency and surround responses in second-order retinal neurons.

Publication types

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

MeSH terms

  • Animals
  • Feedback / physiology
  • Humans
  • Photoreceptor Cells / cytology
  • Photoreceptor Cells / physiology
  • Retina / cytology
  • Retina / physiology*