Shifting from fear to safety through deconditioning-update

  1. Bruno Popik
  2. Felippe Espinelli Amorim
  3. Olavo B Amaral
  4. Lucas Alvares  Is a corresponding author
  1. Universidade Federal do Rio Grande do Sul, Brazil
  2. Universidade Federal do Rio de Janeiro, Brazil

Abstract

Aversive memories are at the heart of psychiatric disorders such as phobias and post-traumatic stress disorder (PTSD). Here, we present a new behavioral approach in rats that robustly attenuates aversive memories. This method consists of 'deconditioning' animals previously trained to associate a tone with a strong footshock by replacing it with a much weaker one during memory retrieval. Our results indicate that deconditioning-update is more effective than traditional extinction in reducing fear responses; moreover, such effects are long lasting and resistant to renewal and spontaneous recovery. Remarkably, this strategy overcame important boundary conditions for memory updating, such as remote or very strong traumatic memories. The same beneficial effect was found in other types of fear-related memories. Deconditioning was mediated by L-type voltage-gated calcium channels and is consistent with computational accounts of mismatch-induced memory updating. Our results suggest that shifting from fear to safety through deconditioning-update is a promising approach to attenuate traumatic memories.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Bruno Popik

    Neurobiology of Memory Lab, Biophysics Department, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
    Competing interests
    The authors declare that no competing interests exist.
  2. Felippe Espinelli Amorim

    Institute of Medical Biochemistry Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
    Competing interests
    The authors declare that no competing interests exist.
  3. Olavo B Amaral

    Institute of Medical Biochemistry Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
    Competing interests
    The authors declare that no competing interests exist.
  4. Lucas Alvares

    Neurobiology of Memory Lab, Biophysics Department, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
    For correspondence
    lucas.alvares@ufrgs.br
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0472-903X

Funding

Conselho Nacional de Desenvolvimento Científico e Tecnológico (Universal 2018 - 405100/2018-3))

  • Lucas Alvares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (graduate fellowship)

  • Bruno Popik

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 followed the Brazilian ethical guidelines for animal research set by the National Council for the Control of Experimental Animal Research (CONCEA) and approved by the committee on the Ethics of Animal Experiments of the UFRGS (number 34547).

Copyright

© 2020, Popik 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. Bruno Popik
  2. Felippe Espinelli Amorim
  3. Olavo B Amaral
  4. Lucas Alvares
(2020)
Shifting from fear to safety through deconditioning-update
eLife 9:e51207.
https://doi.org/10.7554/eLife.51207

Share this article

https://doi.org/10.7554/eLife.51207

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