Multisensory integration in the developing tectum is constrained by the balance of excitation and inhibition

  1. Daniel L Felch
  2. Arseny S Khakhalin
  3. Carlos D Aizenman  Is a corresponding author
  1. Brown University, United States
  2. Bard College, United States

Abstract

Multisensory integration (MSI) is the process that allows the brain to bind together spatiotemporally congruent inputs from different sensory modalities to produce single salient representations. While the phenomenology of MSI in vertebrate brains is well described, relatively little is known about cellular and synaptic mechanisms underlying this phenomenon. Here we use an isolated brain preparation to describe cellular mechanisms underlying development of MSI between visual and mechanosensory inputs in the optic tectum of Xenopus tadpoles. We find MSI is highly dependent on the temporal interval between crossmodal stimulus pairs. Over a key developmental period, the temporal window for MSI significantly narrows and is selectively tuned to specific interstimulus intervals. These changes in MSI correlate with developmental increases in evoked synaptic inhibition, and inhibitory blockade reverses observed developmental changes in MSI. We propose a model in which development of recurrent inhibition mediates development of temporal aspects of MSI in the tectum.

Article and author information

Author details

  1. Daniel L Felch

    Department of Neuroscience, Brown University, Providence, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Arseny S Khakhalin

    Department of Biology, Bard College, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Carlos D Aizenman

    Department of Neuroscience, Brown University, Providence, United States
    For correspondence
    Carlos_Aizenman@brown.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Gary L Westbrook, Vollum Institute, United States

Ethics

Animal experimentation: The Brown University Institutional Animal Care and Use Committee (IACUC) approved all handling of animals in accordance with National Institutes of Health (NIH) guidelines. Experiments were performed under IACUC protocol #1308000008C002, most recently renewed August 12, 2015.

Version history

  1. Received: February 26, 2016
  2. Accepted: May 23, 2016
  3. Accepted Manuscript published: May 24, 2016 (version 1)
  4. Version of Record published: June 17, 2016 (version 2)

Copyright

© 2016, Felch 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. Daniel L Felch
  2. Arseny S Khakhalin
  3. Carlos D Aizenman
(2016)
Multisensory integration in the developing tectum is constrained by the balance of excitation and inhibition
eLife 5:e15600.
https://doi.org/10.7554/eLife.15600

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https://doi.org/10.7554/eLife.15600

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