1. Neuroscience
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General features of the retinal connectome determinethe computation of motion anticipation

  1. Jamie Johnston  Is a corresponding author
  2. Leon Lagnado
  1. University of Sussex, United Kingdom
Research Article
  • Cited 14
  • Views 2,727
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Cite this article as: eLife 2015;4:e06250 doi: 10.7554/eLife.06250

Abstract

Motion anticipation allows the visual system to compensate for the slow speed of phototransduction so that a moving object can be accurately located. This correction is already present in the signal that ganglion cells send from the retina but the biophysical mechanisms underlying this computation are not known. Here we demonstrate that motion anticipation is computed autonomously within the dendritic tree of each ganglion cell and relies on feedforward inhibition. The passive and non-linear interaction of excitatory and inhibitory synapses enables the somatic voltage to encode the actual position of a moving object instead of its delayed representation. General rather than specific features of the retinal connectome govern this computation: an excess of inhibitory inputs over excitatory, with both being randomly distributed, allows tracking of all directions of motion, while the average distance between inputs determines the object velocities that can be compensated for.

Article and author information

Author details

  1. Jamie Johnston

    School of Life Sciences, University of Sussex, Brighton, United Kingdom
    For correspondence
    J.johnston@sussex.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  2. Leon Lagnado

    School of Life Sciences, University of Sussex, Brighton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: All procedures were carried out in accordance with the UK Animals (Scientific Procedures) act 1986 and approved by the local ethical review committee at the University of Sussex.

Reviewing Editor

  1. Matteo Carandini, University College London, United Kingdom

Publication history

  1. Received: December 30, 2014
  2. Accepted: March 17, 2015
  3. Accepted Manuscript published: March 18, 2015 (version 1)
  4. Accepted Manuscript updated: March 19, 2015 (version 2)
  5. Version of Record published: April 13, 2015 (version 3)
  6. Version of Record updated: September 9, 2016 (version 4)

Copyright

© 2015, Johnston & Lagnado

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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