1. Neuroscience
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Noradrenergic projections from the locus coeruleus to the amygdala constrain fear memory reconsolidation

  1. Josué Haubrich  Is a corresponding author
  2. Matteo Bernabo
  3. Karim Nader
  1. McGill University, Canada
Research Article
  • Cited 3
  • Views 1,375
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Cite this article as: eLife 2020;9:e57010 doi: 10.7554/eLife.57010

Abstract

Memory reconsolidation is a fundamental plasticity process in the brain that allows established memories to be changed or erased. However, certain boundary conditions limit the parameters under which memories can be made plastic. Strong memories do not destabilize, for instance, although why they are resilient is mostly unknown. Here, we investigated the hypothesis that specific modulatory signals shape memory formation into a state that is reconsolidation-resistant. We find that the activation of the noradrenaline-locus coeruleus system (NOR-LC) during strong fear memory encoding increases molecular mechanisms of stability at the expense of lability in the amygdala of rats. Preventing the NOR-LC from modulating strong fear encoding results in the formation of memories that can undergo reconsolidation within the amygdala and thus are vulnerable to post-reactivation interference. Thus, the memory strength boundary condition on reconsolidation is set at the time of encoding by the action of the NOR-LC.

Article and author information

Author details

  1. Josué Haubrich

    Department of Psychology, McGill University, Montreal, Canada
    For correspondence
    josue.haubrich@mcgill.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3632-5566
  2. Matteo Bernabo

    Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Karim Nader

    Department of Psychology, McGill University, Montreal, Canada
    Competing interests
    The authors declare that no competing interests exist.

Funding

Natural Sciences and Engineering Research Council of Canada (203523)

  • Karim Nader

Canadian Institutes of Health Research (238757)

  • Karim Nader

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 procedures were approved by McGill's Animal Care Committee (Animal Use Protocol #2000-4512) and complied with the Canadian Council on Animal Care guidelines.

Reviewing Editor

  1. Mihaela D Iordanova, Concordia University, Canada

Publication history

  1. Received: March 17, 2020
  2. Accepted: May 18, 2020
  3. Accepted Manuscript published: May 18, 2020 (version 1)
  4. Version of Record published: June 16, 2020 (version 2)

Copyright

© 2020, Haubrich 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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