Hidden synaptic differences in a neural circuit underlie differential behavioral susceptibility to a neural injury

  1. Akira Sakurai  Is a corresponding author
  2. Arianna N Tamvacakis
  3. Paul S Katz
  1. Neuroscience Institute, Georgia State University, United States

Abstract

Individuals vary in their responses to stroke and trauma, hampering predictions of outcomes. One reason might be that neural circuits contain hidden variability that becomes relevant only when those individuals are challenged by injury. We found that in the mollusc, Tritonia diomedea, subtle differences between animals within the neural circuit underlying swimming behavior had no behavioral relevance under normal conditions but caused differential vulnerability of the behavior to a particular brain lesion. The extent of motor impairment correlated with the site of spike initiation in a specific neuron in the neural circuit, which was determined by the strength of an inhibitory synapse onto this neuron. Artificially increasing or decreasing this inhibitory synaptic conductance with dynamic clamp correspondingly altered the extent of motor impairment by lesion without affecting normal operation. The results suggest that neural circuit differences could serve as hidden phenotypes for predicting the behavioral outcome of neural damage.

Article and author information

Author details

  1. Akira Sakurai

    Neuroscience Institute, Georgia State University, Atlanta, United States
    For correspondence
    akira@gsu.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Arianna N Tamvacakis

    Neuroscience Institute, Georgia State University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Paul S Katz

    Neuroscience Institute, Georgia State University, Atlanta, United States
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: The animals are housed in appropriately sized tanks equipped with temperature control system. They are routinely fed and cold-anesthetized prior to dissection.

Reviewing Editor

  1. Ronald L Calabrese, Emory University, United States

Version history

  1. Received: February 21, 2014
  2. Accepted: June 9, 2014
  3. Accepted Manuscript published: June 11, 2014 (version 1)
  4. Version of Record published: July 15, 2014 (version 2)

Copyright

© 2014, Sakurai et al.

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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  1. Akira Sakurai
  2. Arianna N Tamvacakis
  3. Paul S Katz
(2014)
Hidden synaptic differences in a neural circuit underlie differential behavioral susceptibility to a neural injury
eLife 3:e02598.
https://doi.org/10.7554/eLife.02598

Share this article

https://doi.org/10.7554/eLife.02598

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