Online integration of sensory and emotional (fear) memories in the rat medial temporal lobe

  1. Francesca S Wong
  2. R Fred Westbrook
  3. Nathan M Holmes  Is a corresponding author
  1. University of New South Wales, Australia

Abstract

How does a stimulus never associated with danger become frightening? The present study addressed this question using a sensory preconditioning task with rats. In this task, rats integrate a sound-light memory formed in stage 1 with a light-danger memory formed in stage 2, as they show fear when tested with the sound in stage 3. Here we show that this integration occurs 'online' during stage 2: when activity in the region that consolidated the sound-light memory (perirhinal cortex) was inhibited during formation of the light-danger memory, rats no longer showed fear when tested with the sound but continued to fear the light. Thus, fear that accrues to a stimulus paired with danger simultaneously spreads to its past associates, thereby roping those associates into a fear memory network.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1, 2, 4 and 5.

Article and author information

Author details

  1. Francesca S Wong

    School of Psychology, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. R Fred Westbrook

    School of Psychology, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  3. Nathan M Holmes

    School of Psychology, University of New South Wales, Sydney, Australia
    For correspondence
    n.holmes@unsw.edu.au
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0592-2026

Funding

Australian Research Council (DP170103952)

  • Nathan M Holmes

National Health and Medical Research Council (APP1146999)

  • Nathan M Holmes

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 guidelines published by the National Health and Medical Research Council in Australia. All of the animals were handled according to approved Animal Care and Ethics Committee (ACEC) protocols at the University of New South Wales (Permit Number: ACEC 17/139A). All surgery was performed under ketamine-xylazine induced anesthesia, and every effort was made to minimize suffering.

Reviewing Editor

  1. Thorsten Kahnt, Northwestern University Feinberg School of Medicine, United States

Publication history

  1. Received: March 22, 2019
  2. Accepted: June 10, 2019
  3. Accepted Manuscript published: June 10, 2019 (version 1)
  4. Version of Record published: June 25, 2019 (version 2)

Copyright

© 2019, Wong 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. Francesca S Wong
  2. R Fred Westbrook
  3. Nathan M Holmes
(2019)
Online integration of sensory and emotional (fear) memories in the rat medial temporal lobe
eLife 8:e47085.
https://doi.org/10.7554/eLife.47085

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