1. Computational and Systems Biology
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Mixed-mode oscillations and population bursting in the pre-Bӧtzinger complex

  1. Bartholomew J Bacak  Is a corresponding author
  2. Taegyo Kim
  3. Jeffrey C Smith
  4. Jonathan E Rubin
  5. Ilya A Rybak
  1. Drexel University College of Medicine, United States
  2. National Institutes of Health, United States
  3. University of Pittsburgh, United States
Research Article
  • Cited 17
  • Views 1,421
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Cite this article as: eLife 2016;5:e13403 doi: 10.7554/eLife.13403

Abstract

This study focuses on computational and theoretical investigations of neuronal activity arising in the pre-Bӧtzinger complex (pre-BӧtC), a medullary region generating the inspiratory phase of breathing in mammals. A progressive increase of neuronal excitability in medullary slices containing the pre-BӧtC produces mixed-mode oscillations (MMOs) characterized by large amplitude population bursts alternating with a series of small amplitude bursts. Using two different computational models, we demonstrate that MMOs emerge within a heterogeneous excitatory neural network because of progressive neuronal recruitment and synchronization. The MMO pattern depends on the distributed neuronal excitability, the density and weights of network interconnections, and the cellular properties underlying endogenous bursting. Critically, the latter should provide a reduction of spiking frequency within neuronal bursts with increasing burst frequency and a dependence of the after-burst recovery period on burst amplitude. Our study highlights a novel mechanism by which heterogeneity naturally leads to complex dynamics in rhythmic neuronal populations.

Article and author information

Author details

  1. Bartholomew J Bacak

    Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, United States
    For correspondence
    BartBacak@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
  2. Taegyo Kim

    Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jeffrey C Smith

    Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Jonathan E Rubin

    Department of Mathematics, University of Pittsburgh, Pittsburgh, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Ilya A Rybak

    Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Jan-Marino Ramirez, Seattle Children's Research Institute and University of Washington, United States

Publication history

  1. Received: November 29, 2015
  2. Accepted: March 11, 2016
  3. Accepted Manuscript published: March 14, 2016 (version 1)
  4. Version of Record published: April 21, 2016 (version 2)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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