The cortical connectivity of the periaqueductal gray and the conditioned response to the threat of breathlessness

  1. Olivia K Faull  Is a corresponding author
  2. Kyle TS Pattinson
  1. University of Oxford, United Kingdom

Abstract

Previously we observed differential activation in individual columns of the periaqueductal grey (PAG) during breathlessness and its conditioned anticipation (Faull et al., 2016). Here, we have extended this work by determining how the individual columns of the PAG interact with higher cortical centres, both at rest and in the context of breathlessness threat. Activation was observed in ventrolateral PAG (vlPAG) and lateral PAG (lPAG), where activity scaled with breathlessness intensity ratings, revealing a potential interface between sensation and cognition during breathlessness. At rest the lPAG was functionally correlated with cortical sensorimotor areas, conducive to facilitating fight/flight responses, and demonstrated increased synchronicity with the amygdala during breathlessness. The vlPAG showed fronto-limbic correlations at rest, whereas during breathlessness anticipation, reduced functional synchronicity was seen to both lPAG and motor structures, conducive to freezing behaviours. These results move us towards understanding how the PAG might be intricately involved in human responses to threat.

Article and author information

Author details

  1. Olivia K Faull

    FMRIB Centre, University of Oxford, Oxford, United Kingdom
    For correspondence
    olivia.faull@ndcn.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0897-7142
  2. Kyle TS Pattinson

    FMRIB Centre, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Funding

JABBS (HMR00210)

  • Olivia K Faull
  • Kyle TS Pattinson

National Institute for Health Research

  • Kyle TS Pattinson

Medical Research Council

  • Kyle TS Pattinson

Commonwealth Scholarship Commission

  • Olivia K Faull

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

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

Copyright

© 2017, Faull & Pattinson

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. Kyle TS Pattinson
(2017)
The cortical connectivity of the periaqueductal gray and the conditioned response to the threat of breathlessness
eLife 6:e21749.
https://doi.org/10.7554/eLife.21749

Share this article

https://doi.org/10.7554/eLife.21749

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