The pupillary light response as a physiological index of aphantasia, sensory and phenomenological imagery strength

  1. Lachlan Kay
  2. Rebecca Keogh  Is a corresponding author
  3. Thomas Andrillon
  4. Joel Pearson
  1. University of New South Wales, Australia
  2. Macquarie University, Australia
  3. Sorbonne Université, France

Abstract

The pupillary light response is an important automatic physiological response which optimises light reaching the retina. Recent work has shown that the pupil also adjusts in response to illusory brightness and a range of cognitive functions, however, it remains unclear what exactly drives these endogenous changes. Here we show that the imagery pupillary light response correlates with objective measures of sensory imagery strength. Further, the trial-by-trial phenomenological vividness of visual imagery is tracked by the imagery pupillary light response. We also demonstrated that a group of individuals without visual imagery (aphantasia) do not show any significant evidence of an imagery pupillary light response, however they do show perceptual pupil light responses and pupil dilation with larger cognitive load. Our results provide evidence that the pupillary light response indexes the sensory strength of visual imagery and this work also provides the first physiological validation of aphantasia.

Data availability

Figure 1 - Source Data 1& 2, Figure 2 - Source Data 3, and Figure 3 - Source Data 4 contain the numerical data used to generate the figures.

Article and author information

Author details

  1. Lachlan Kay

    School of Psychology, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. Rebecca Keogh

    School of Psychological Sciences, Macquarie University, Sydney, Australia
    For correspondence
    rebeccalkeogh@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4814-433X
  3. Thomas Andrillon

    Institut du Cerveau - Paris Brain Institute, Sorbonne Université, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Joel Pearson

    School of Psychology, University of New South Wales, Sydney, Australia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3704-5037

Funding

National Health and Medical Research Council (APP1024800)

  • Joel Pearson

National Health and Medical Research Council (APP1046198)

  • Joel Pearson

National Health and Medical Research Council (APP1085404)

  • Joel Pearson

National Health and Medical Research Council (APP1049596)

  • Joel Pearson

Australian Research Council (DP140101560)

  • Joel Pearson

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

Ethics

Human subjects: Informed written consent was obtained from all participants to participate in the experiment and to publish their anonymised data in a journal article. Both experiments were approved by the UNSW Human Research Ethics Advisory Panel (HREAP-C 3182).

Reviewing Editor

  1. John T Serences, University of California, San Diego, United States

Publication history

  1. Received: July 26, 2021
  2. Preprint posted: September 3, 2021 (view preprint)
  3. Accepted: March 30, 2022
  4. Accepted Manuscript published: March 31, 2022 (version 1)
  5. Version of Record published: April 19, 2022 (version 2)

Copyright

© 2022, Kay 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. Lachlan Kay
  2. Rebecca Keogh
  3. Thomas Andrillon
  4. Joel Pearson
(2022)
The pupillary light response as a physiological index of aphantasia, sensory and phenomenological imagery strength
eLife 11:e72484.
https://doi.org/10.7554/eLife.72484
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