How Diverse Retinal Functions Arise from Feedback at the First Visual Synapse

Neuron. 2018 Jul 11;99(1):117-134.e11. doi: 10.1016/j.neuron.2018.06.001. Epub 2018 Jun 21.

Abstract

Many brain regions contain local interneurons of distinct types. How does an interneuron type contribute to the input-output transformations of a given brain region? We addressed this question in the mouse retina by chemogenetically perturbing horizontal cells, an interneuron type providing feedback at the first visual synapse, while monitoring the light-driven spiking activity in thousands of ganglion cells, the retinal output neurons. We uncovered six reversible perturbation-induced effects in the response dynamics and response range of ganglion cells. The effects were enhancing or suppressive, occurred in different response epochs, and depended on the ganglion cell type. A computational model of the retinal circuitry reproduced all perturbation-induced effects and led us to assign specific functions to horizontal cells with respect to different ganglion cell types. Our combined experimental and theoretical work reveals how a single interneuron type can differentially shape the dynamical properties of distinct output channels of a brain region.

Keywords: cell type; computation; ganglion cell; horizontal cell; inhibition; interneuron; model; neuronal circuit; non-linear neural processing; retina.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism
  • Feedback*
  • Interneurons / physiology*
  • Mice
  • Models, Neurological
  • Photoreceptor Cells, Vertebrate
  • Retinal Bipolar Cells
  • Retinal Ganglion Cells / physiology*
  • Retinal Horizontal Cells / physiology*
  • Synapses
  • Vision, Ocular / physiology*

Substances

  • Calcium