Conditioned respiratory threat in the subdivisions of the human periaqueductal gray

  1. Olivia K Faull  Is a corresponding author
  2. Mark Jenkinson
  3. Martyn Ezra
  4. Kyle T.S Pattinson
  1. University of Oxford, United Kingdom

Abstract

The sensation of breathlessness is the most threatening symptom of respiratory disease. The different subdivisions of the midbrain periaqueductal gray (PAG) are intricately (and differentially) involved in integrating behavioural responses to threat in animals, while the PAG has previously only been considered as a single entity in human research. Here we investigate how these individual PAG columns are differently involved with respiratory threat. Eighteen healthy subjects were conditioned to associate shapes with certain or uncertain impending respiratory load, and scanned the following day during anticipation and application of inspiratory loading using 7 T functional MRI. We showed activity in the ventrolateral PAG (vlPAG) during anticipation of resistive loading, with activity in the lateral PAG (lPAG) during resistive loading, showing spatially and temporally distinct functions within this structure. We propose that lPAG is involved with sensorimotor responses to breathlessness, while the vlPAG operates within the threat perception network for impending breathlessness.

Article and author information

Author details

  1. Olivia K Faull

    Oxford Centre for Functional MRI of the Brain, University of Oxford, Oxford, United Kingdom
    For correspondence
    olivia.faull@ndcn.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  2. Mark Jenkinson

    Oxford Centre for Functional MRI of the Brain, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Martyn Ezra

    Oxford Centre for Functional MRI of the Brain, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Kyle T.S Pattinson

    Oxford Centre for Functional MRI of the Brain, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Human subjects: The Oxfordshire Clinical Research Ethics Committee approved the study and volunteers gave written, informed consent prior to testing.

Copyright

© 2016, Faull 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. Olivia K Faull
  2. Mark Jenkinson
  3. Martyn Ezra
  4. Kyle T.S Pattinson
(2016)
Conditioned respiratory threat in the subdivisions of the human periaqueductal gray
eLife 5:e12047.
https://doi.org/10.7554/eLife.12047

Share this article

https://doi.org/10.7554/eLife.12047

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