1. Neuroscience
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A transformation from temporal to ensemble coding in a model of piriform cortex

  1. Merav Stern
  2. Kevin A Bolding
  3. Larry F Abbott
  4. Kevin M Franks  Is a corresponding author
  1. Hebrew University, Israel
  2. Duke University Medical School, United States
  3. Columbia University, United States
  4. Duke University School of Medicine, United States
Research Article
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Cite this article as: eLife 2018;7:e34831 doi: 10.7554/eLife.34831

Abstract

Different coding strategies are used to represent odor information at various stages of the mammalian olfactory system. A temporal latency code represents odor identity in olfactory bulb (OB), but this temporal information is discarded in piriform cortex (PCx) where odor identity is instead encoded through ensemble membership. We developed a spiking PCx network model to understand how this transformation is implemented. In the model, the impact of OB inputs activated earliest after inhalation is amplified within PCx by diffuse recurrent collateral excitation, which then recruits strong, sustained feedback inhibition that suppresses the impact of later-responding glomeruli. We model increasing odor concentrations by decreasing glomerulus onset latencies while preserving their activation sequences. This produces a multiplexed cortical odor code in which activated ensembles are robust to concentration changes while concentration information is encoded through population synchrony. Our model demonstrates how PCx circuitry can implement multiplexed ensemble-identity/temporal-concentration odor coding.

Article and author information

Author details

  1. Merav Stern

    Edmond and Lily Safra Center for Brain Sciences, Hebrew University, Jerusalem, Israel
    Competing interests
    The authors declare that no competing interests exist.
  2. Kevin A Bolding

    Department of Neurobiology, Duke University Medical School, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2271-5280
  3. Larry F Abbott

    Department of Neuroscience, Columbia University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Kevin M Franks

    Department of Neurobiology, Duke University School of Medicine, Durham, United States
    For correspondence
    franks@neuro.duke.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6386-9518

Funding

National Institute on Deafness and Other Communication Disorders (DC015525)

  • Kevin M Franks

National Institute on Deafness and Other Communication Disorders (DC016782)

  • Kevin M Franks

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All experimental protocols were approved by Duke University Institutional Animal Care and Use Committee (protocol # A220-15-08), which was approved on 08-27-2015.

Reviewing Editor

  1. Naoshige Uchida, Harvard University, United States

Publication history

  1. Received: January 5, 2018
  2. Accepted: March 20, 2018
  3. Accepted Manuscript published: March 29, 2018 (version 1)
  4. Version of Record published: April 16, 2018 (version 2)

Copyright

© 2018, Stern 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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