Sucrose intensity coding and decision-making in rat gustatory cortices

  1. Esmeralda Fonseca
  2. Victor de Lafuente
  3. Sidney Simon
  4. Ranier Gutierrez  Is a corresponding author
  1. CINVESTAV, Mexico
  2. National Autonomous University of Mexico, Mexico
  3. Duke University, United States

Abstract

Sucrose's sweet intensity is one attribute contributing to the overconsumption of high-energy palatable foods. However, it is not known how sucrose intensity is encoded and used to make perceptual decisions by neurons in taste-sensitive cortices. We trained rats in a sucrose intensity discrimination task and found that sucrose evoked a widespread response in neurons recorded in posterior-Insula (pIC), anterior-Insula (aIC), and Orbitofrontal cortex (OFC). Remarkably, only a few Intensity-selective neurons conveyed the most information about sucrose's intensity, indicating that for sweetness the gustatory system used a compact and distributed code. Sucrose intensity was encoded in both firing-rates and spike-timing. The pIC, aIC, and OFC neurons tracked movement direction, with OFC neurons yielding the most robust response. aIC and OFC neurons encoded the subject's choices, whereas all three regions tracked reward omission. Overall, these multimodal areas provide a neural representation of perceived sucrose intensity, and of task-related information underlying perceptual decision-making.

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. Esmeralda Fonseca

    Department of Pharmacology, CINVESTAV, Mexico City, Mexico
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3697-9401
  2. Victor de Lafuente

    Institute of Neurobiology, National Autonomous University of Mexico, Querétaro, Mexico
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1047-1354
  3. Sidney Simon

    Department of Neurobiology, Duke University, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Ranier Gutierrez

    Department of Pharmacology, CINVESTAV, Mexico City, Mexico
    For correspondence
    ranier@cinvestav.mx
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9688-0289

Funding

Consejo Nacional de Ciencia y Tecnología (Problemas Nacionales 464)

  • Ranier Gutierrez

Productos Medix (3247)

  • Ranier Gutierrez

Consejo Nacional de Ciencia y Tecnología (FOINS 63)

  • Ranier Gutierrez

Consejo Nacional de Ciencia y Tecnología (FOINS 245)

  • Victor de Lafuente

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 the CINVESTAV Institutional Animal Care and Use Committee (#0034-13)

Reviewing Editor

  1. Geoffrey Schoenbaum, National Institute on Drug Abuse, National Institutes of Health, United States

Publication history

  1. Received: August 16, 2018
  2. Accepted: November 16, 2018
  3. Accepted Manuscript published: November 19, 2018 (version 1)
  4. Version of Record published: December 13, 2018 (version 2)

Copyright

© 2018, Fonseca 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. Esmeralda Fonseca
  2. Victor de Lafuente
  3. Sidney Simon
  4. Ranier Gutierrez
(2018)
Sucrose intensity coding and decision-making in rat gustatory cortices
eLife 7:e41152.
https://doi.org/10.7554/eLife.41152
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