Complementary codes for odor identity and intensity in olfactory cortex

  1. Kevin A Bolding
  2. Kevin M Franks  Is a corresponding author
  1. Duke University Medical School, United States

Abstract

The ability to represent both stimulus identity and intensity is fundamental for perception. Using large-scale population recordings in awake mice, we find distinct coding strategies facilitate non-interfering representations of odor identity and intensity in piriform cortex. Simply knowing which neurons were activated is sufficient to accurately represent odor identity, with no additional information about identity provided by spike time or spike count. Decoding analyses indicate that cortical odor representations are not sparse. Odorant concentration had no systematic effect on spike counts, indicating that rate cannot encode intensity. Instead, odor intensity can be encoded by temporal features of the population response. We found a subpopulation of rapid, largely concentration-invariant responses was followed by another population of responses whose latencies systematically decreased at higher concentrations. Cortical inhibition transforms olfactory bulb output to sharpen these dynamics. Our data therefore reveal complementary coding strategies that can selectively represent distinct features of a stimulus.

Article and author information

Author details

  1. Kevin A Bolding

    Department of Neurobiology, Duke University Medical School, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Kevin M Franks

    Department of Neurobiology, Duke University Medical School, 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 Institutes of Health (DC009839)

  • Kevin M Franks

National Institutes of Health (DC015525)

  • Kevin M Franks

Edward Mallinckrodt Jr. Foundation

  • Kevin M Franks

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

Reviewing Editor

  1. Upinder S Bhalla, National Centre for Biological Sciences, India

Ethics

Animal experimentation: All experimental protocols were approved by Duke University Institutional Animal Care and Use Committee according to protocols A243-12-09 and A220-15-08.

Version history

  1. Received: October 24, 2016
  2. Accepted: April 1, 2017
  3. Accepted Manuscript published: April 5, 2017 (version 1)
  4. Version of Record published: May 19, 2017 (version 2)

Copyright

© 2017, Bolding & Franks

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. Kevin A Bolding
  2. Kevin M Franks
(2017)
Complementary codes for odor identity and intensity in olfactory cortex
eLife 6:e22630.
https://doi.org/10.7554/eLife.22630

Share this article

https://doi.org/10.7554/eLife.22630

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