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
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
- Mathieu Wolff, CNRS, University of Bordeaux, France
Version history
- Received: January 19, 2021
- Accepted: June 29, 2021
- Accepted Manuscript published: July 5, 2021 (version 1)
- 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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