NMDA spikes mediate amplification of inputs in the rat piriform cortex

  1. Amit Kumar
  2. Oded Schiff
  3. Edi Barkai
  4. Bartlett W Mel  Is a corresponding author
  5. Alon Poleg-Polsky  Is a corresponding author
  6. Jackie Schiller  Is a corresponding author
  1. Technion-Israel Institute of Technology, Israel
  2. University of Haifa, Israel
  3. University of Southern California, United States
  4. University of Colorado School of Medicine, United States

Abstract

The piriform cortex (PCx) receives direct input from the olfactory bulb (OB) and is the brain's main station for odor recognition and memory. The transformation of the odor code from OB to PCx is profound: mitral and tufted cells in olfactory glomeruli respond to individual odorant molecules, whereas pyramidal neurons (PNs) in the PCx responds to multiple, apparently random combinations of activated glomeruli. How these 'discontinuous' receptive fields are formed from OB inputs remains unknown. Counter to the prevailing view that olfactory PNs sum their inputs passively, we show for the first time that NMDA spikes within individual dendrites can both amplify OB inputs and impose combination selectivity upon them, while their ability to compartmentalize voltage signals allows different dendrites to represent different odorant combinations. Thus, the 2-layer integrative behavior of olfactory PN dendrites provides a parsimonious account for the nonlinear remapping of the odor code from bulb to cortex.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Amit Kumar

    Department of Physiology, Technion-Israel Institute of Technology, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0674-3641
  2. Oded Schiff

    Department of Physiology, Technion-Israel Institute of Technology, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
  3. Edi Barkai

    Department of Neurobiology, University of Haifa, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7325-4269
  4. Bartlett W Mel

    Biomedical Engineering Department, University of Southern California, Los Angeles, United States
    For correspondence
    mel@usc.edu
    Competing interests
    The authors declare that no competing interests exist.
  5. Alon Poleg-Polsky

    Department of Physiology and Biophysics, University of Colorado School of Medicine, Aurora, United States
    For correspondence
    ALON.POLEG-POLSKY@UCDENVER.EDU
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1327-5129
  6. Jackie Schiller

    Department of Physiology, Technion-Israel Institute of Technology, Haifa, Israel
    For correspondence
    jackie@technion.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9182-7166

Funding

Israeli Science Foundation

  • Jackie Schiller

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 animal procedures were in accordance with guidelines established by the NIH on the care and use of animals in research and were confirmed by the Technion Institutional Animal Care and Use Committee (IL-012-01-18, valid until 10/4/2022).

Reviewing Editor

  1. Naoshige Uchida, Harvard University, United States

Publication history

  1. Received: May 18, 2018
  2. Accepted: December 20, 2018
  3. Accepted Manuscript published: December 21, 2018 (version 1)
  4. Version of Record published: January 15, 2019 (version 2)

Copyright

© 2018, Kumar 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. Amit Kumar
  2. Oded Schiff
  3. Edi Barkai
  4. Bartlett W Mel
  5. Alon Poleg-Polsky
  6. Jackie Schiller
(2018)
NMDA spikes mediate amplification of inputs in the rat piriform cortex
eLife 7:e38446.
https://doi.org/10.7554/eLife.38446

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