Insula to mPFC reciprocal connectivity differentially underlies novel taste neophobic response and learning

Abstract

To survive in an ever-changing environment, animals must detect and learn salient information. The anterior insular cortex (aIC) and medial prefrontal cortex (mPFC) are heavily implicated in salience and novelty processing, and specifically, the processing of taste sensory information. Here, we examined the role of aIC-mPFC reciprocal connectivity in novel taste neophobia and memory formation, in mice. Using pERK and neuronal intrinsic properties as markers for neuronal activation, and retrograde AAV (rAAV) constructs for connectivity, we demonstrate a correlation between aIC-mPFC activity and novel taste experience. Furthermore, by expressing inhibitory chemogenetic receptors in these projections, we show that aIC-to-mPFC activity is necessary for both taste neophobia and its attenuation. However, activity within mPFC-to-aIC projections is essential only for the neophobic reaction but not for the learning process. These results provide an insight into the cortical circuitry needed to detect, react to- and learn salient stimuli, a process critically involved in psychiatric disorders.

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 all Figures

Article and author information

Author details

  1. Haneen Kayyal

    Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4429-3514
  2. Sailendrakumar Kolatt Chandran

    Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9805-8096
  3. Adonis Yiannakas

    Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
  4. Nathaniel Gould

    Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
  5. Mohammad Khamaisy

    Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
    Competing interests
    The authors declare that no competing interests exist.
  6. Kobi Rosenblum

    Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
    For correspondence
    kobir@psy.haifa.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4827-0336

Funding

Israel Science Foundation (isf 946/17)

  • Kobi Rosenblum

Israel Science Foundation (isf 258/20)

  • Kobi Rosenblum

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 experiments and procedures conducted were approved by the University of Haifa Animal Care and Use committee under Ethical license 554/18 and were in accordance with the National Institutes of Health guidelines for ethical treatment of animals.

Reviewing Editor

  1. Mathieu Wolff, CNRS, University of Bordeaux, France

Publication history

  1. Received: January 19, 2021
  2. Accepted: June 29, 2021
  3. Accepted Manuscript published: July 5, 2021 (version 1)
  4. Version of Record published: July 15, 2021 (version 2)

Copyright

© 2021, Kayyal 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. Haneen Kayyal
  2. Sailendrakumar Kolatt Chandran
  3. Adonis Yiannakas
  4. Nathaniel Gould
  5. Mohammad Khamaisy
  6. Kobi Rosenblum
(2021)
Insula to mPFC reciprocal connectivity differentially underlies novel taste neophobic response and learning
eLife 10:e66686.
https://doi.org/10.7554/eLife.66686
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