A Role for Synaptic Input Distribution in a Dendritic Computation of Motion Direction in the Retina

Neuron. 2016 Mar 16;89(6):1317-1330. doi: 10.1016/j.neuron.2016.02.020.


The starburst amacrine cell in the mouse retina presents an opportunity to examine the precise role of sensory input location on neuronal computations. Using visual receptive field mapping, glutamate uncaging, two-photon Ca(2+) imaging, and genetic labeling of putative synapses, we identify a unique arrangement of excitatory inputs and neurotransmitter release sites on starburst amacrine cell dendrites: the excitatory input distribution is skewed away from the release sites. By comparing computational simulations with Ca(2+) transients recorded near release sites, we show that this anatomical arrangement of inputs and outputs supports a dendritic mechanism for computing motion direction. Direction-selective Ca(2+) transients persist in the presence of a GABA-A receptor antagonist, though the directional tuning is reduced. These results indicate a synergistic interaction between dendritic and circuit mechanisms for generating direction selectivity in the starburst amacrine cell.

Publication types

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

MeSH terms

  • Acetylcholinesterase / genetics
  • Acetylcholinesterase / metabolism
  • Amacrine Cells / drug effects
  • Amacrine Cells / physiology*
  • Animals
  • Animals, Newborn
  • Calcium / metabolism
  • Computer Simulation
  • Dendrites / physiology*
  • Disks Large Homolog 4 Protein
  • Excitatory Postsynaptic Potentials / drug effects
  • Excitatory Postsynaptic Potentials / physiology
  • Glutamic Acid / pharmacology
  • Guanylate Kinases / metabolism
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Models, Neurological*
  • Motion Perception / drug effects
  • Motion Perception / physiology*
  • Orientation / physiology*
  • Receptors, AMPA / genetics
  • Receptors, AMPA / metabolism
  • Retina / cytology*
  • Synapses / drug effects
  • Synapses / physiology*
  • Synapses / ultrastructure
  • Visual Pathways / physiology


  • Disks Large Homolog 4 Protein
  • Dlg4 protein, mouse
  • Membrane Proteins
  • Receptors, AMPA
  • Glutamic Acid
  • Guanylate Kinases
  • Acetylcholinesterase
  • glutamate receptor ionotropic, AMPA 2
  • Calcium