Phasic and tonic neuron ensemble codes for stimulus-environment conjunctions in the lateral entorhinal cortex

  1. Maryna Pilkiw
  2. Nathan Insel
  3. Younghua Cui
  4. Caitlin Finney
  5. Mark D Morrissey
  6. Kaori Takehara-Nishiuchi  Is a corresponding author
  1. University of Toronto, Canada
  2. University of Montana, United States
  3. University or Toronto, Canada

Abstract

The lateral entorhinal cortex (LEC) is thought to bind sensory events with the environment where they took place. To compare the relative influence of transient events and temporally stable environmental stimuli on the firing of LEC cells, we recorded neuron spiking patterns in the region during blocks of a trace eyeblink conditioning paradigm performed in two environments and with different conditioning stimuli. Firing rates of some neurons were phasically selective for conditioned stimuli in a way that depended on which room the rat was in; nearly all neurons were tonically selective for environments in a way that depended on which stimuli had been presented in those environments. As rats moved from one environment to another, tonic neuron ensemble activity exhibited prospective information about the conditioned stimulus associated with the environment. Thus, the LEC formed phasic and tonic codes for event-environment associations, thereby accurately differentiating multiple experiences with overlapping features.

Article and author information

Author details

  1. Maryna Pilkiw

    Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1200-1708
  2. Nathan Insel

    Department of Psychology, University of Montana, Missoula, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Younghua Cui

    Department of Psychology, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Caitlin Finney

    Department of Psychology, University of Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  5. Mark D Morrissey

    Department of Psychology, University or Toronto, Toronto, Canada
    Competing interests
    The authors declare that no competing interests exist.
  6. Kaori Takehara-Nishiuchi

    Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
    For correspondence
    takehara@psych.utoronto.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7282-7838

Funding

Natural Sciences and Engineering Research Council of Canada (RGPIN-2015-05458)

  • Kaori Takehara-Nishiuchi

Canadian Institutes of Health Research (MOP-133693)

  • Kaori Takehara-Nishiuchi

Canada Foundation for Innovation (25026)

  • Kaori Takehara-Nishiuchi

Natural Sciences and Engineering Research Council of Canada (396157093)

  • Maryna Pilkiw

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

Reviewing Editor

  1. Geoffrey Schoenbaum, National Institutes of Health, United States

Ethics

Animal experimentation: All surgical and experimental procedures were approved by the Animal Care and Use Committee at the University of Toronto (protocol number: 20011400).

Version history

  1. Received: May 13, 2017
  2. Accepted: July 5, 2017
  3. Accepted Manuscript published: July 6, 2017 (version 1)
  4. Version of Record published: July 31, 2017 (version 2)

Copyright

© 2017, Pilkiw 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. Maryna Pilkiw
  2. Nathan Insel
  3. Younghua Cui
  4. Caitlin Finney
  5. Mark D Morrissey
  6. Kaori Takehara-Nishiuchi
(2017)
Phasic and tonic neuron ensemble codes for stimulus-environment conjunctions in the lateral entorhinal cortex
eLife 6:e28611.
https://doi.org/10.7554/eLife.28611

Share this article

https://doi.org/10.7554/eLife.28611

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