Medial entorhinal cortex activates in a traveling wave in the rat

  1. Jesus J Hernández-Pérez  Is a corresponding author
  2. Keiland W Cooper
  3. Ehren L Newman
  1. Indiana University Bloomington, United States

Abstract

Traveling waves are hypothesized to support the long-range coordination of anatomically distributed circuits. Whether separate strongly-interacting circuits exhibit traveling waves remains unknown. The hippocampus exhibits traveling 'theta' waves and interacts strongly with the medial entorhinal cortex (MEC). To determine whether the MEC also activates in a traveling wave, we performed extracellular recordings of LFP and multi-unit activity along the MEC. These recordings revealed progressive phase shifts in activity, indicating that the MEC also activates in a traveling wave. Variation in theta waveform along the region, generated by gradients in local physiology, contributed to the observed phase shifts. Removing waveform-related phase shifts left significant residual phase shifts. The residual phase shifts covaried with theta frequency in a manner consistent with those generated by weakly coupled oscillators. These results show that coordination of anatomically distributed circuits could be enabled by traveling waves but reveal heterogeneity in the mechanisms generating those waves.

Data availability

Data files have bee be uploaded to crcns.org http://dx.doi.org/10.6080/K0C53J2R

The following data sets were generated

Article and author information

Author details

  1. Jesus J Hernández-Pérez

    Department of Psychological and Brain Sciences, Indiana University Bloomington, Bloomington, United States
    For correspondence
    jjhern@iu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6963-4712
  2. Keiland W Cooper

    Department of Psychological and Brain Sciences, Indiana University Bloomington, Bloomington, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0358-9645
  3. Ehren L Newman

    Department of Psychological and Brain Sciences, Indiana University Bloomington, Bloomington, United States
    Competing interests
    The authors declare that no competing interests exist.

Funding

Whitehall Foundation

  • Ehren L Newman

Consejo Nacional de Ciencia y Tecnología (232364)

  • Jesus J Hernández-Pérez

Indiana University Bloomington

  • Ehren L Newman

The funders provided resources for the study design, data collection, and interpretation.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#18-026) of Indiana University, Bloomington. The protocol was approved by the Committee on the Ethics of Animal Experiments of Indiana University, Bloomington (Animal Welfare Assurance Number D16-00587). All surgery was performed under isoflurane anesthesia, and every effort was made to minimize suffering.

Reviewing Editor

  1. Neil Burgess, University College London, United Kingdom

Version history

  1. Received: September 28, 2019
  2. Accepted: February 4, 2020
  3. Accepted Manuscript published: February 14, 2020 (version 1)
  4. Version of Record published: February 27, 2020 (version 2)

Copyright

© 2020, Hernández-Pérez 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. Jesus J Hernández-Pérez
  2. Keiland W Cooper
  3. Ehren L Newman
(2020)
Medial entorhinal cortex activates in a traveling wave in the rat
eLife 9:e52289.
https://doi.org/10.7554/eLife.52289

Share this article

https://doi.org/10.7554/eLife.52289

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