1. Neuroscience
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Structured inhibitory activity dynamics in new virtual environments

  1. Moises Arriaga
  2. Edward B Han  Is a corresponding author
  1. Washington University School of Medicine, United States
Research Article
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Cite this article as: eLife 2019;8:e47611 doi: 10.7554/eLife.47611

Abstract

Inhibition plays a powerful role in regulating network excitation and plasticity; however, the activity of defined interneuron types during spatial exploration remain poorly understood. Using two-photon calcium imaging, we recorded hippocampal CA1 somatostatin- and parvalbumin-expressing interneurons as mice performed a goal-directed spatial navigation task in new visual virtual reality (VR) contexts. Activity in both interneuron classes was strongly suppressed but recovered as animals learned to adapt the previously learned task to the new spatial context. Surprisingly, although there was a range of activity suppression across the population, individual somatostatin-expressing interneurons showed consistent levels of activity modulation across exposure to multiple novel environments, suggesting context-independent, stable network roles during spatial exploration. This work reveals population-level temporally dynamic interneuron activity in new environments, within which each interneuron shows stable and consistent activity modulation.

Data availability

Source data are available at Dryad digital repository under the DOI 10.5061/dryad.f83kt85. Code to analyse the data has been deposited to GitHub at https://github.com/Han-Lab-WUSM/MA-scripts (commit 54efc13).

The following data sets were generated

Article and author information

Author details

  1. Moises Arriaga

    Department of Neuroscience, Washington University School of Medicine, St Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Edward B Han

    Department of Neuroscience, Washington University School of Medicine, St Louis, United States
    For correspondence
    ehan23@wustl.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1009-2186

Funding

McDonnell Center for Systems Neuroscience

  • Edward B Han

McDonnell Center for Cellular and Molecular Neurobiology

  • Edward B Han

Cognitive, Computational, Systems Neuroscience Pathway at Washington University in St. Louis (Graduate Student Fellowship)

  • Moises Arriaga

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

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 of Washington University (Animal Welfare Assurance # A-3381-01). The protocol was approved by the Washington University School of Medicine IACUC (#20170230). All surgery was performed under isofluorane anesthesia, and every effort was made to minimize suffering.

Reviewing Editor

  1. Helen Scharfman, New York University Langone Medical Center, United States

Publication history

  1. Received: April 11, 2019
  2. Accepted: October 5, 2019
  3. Accepted Manuscript published: October 8, 2019 (version 1)
  4. Version of Record published: November 12, 2019 (version 2)

Copyright

© 2019, Arriaga & Han

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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