The pupillary light response as a physiological index of aphantasia, sensory and phenomenological imagery strength
- University of New South Wales, Australia
- Macquarie University, Australia
- 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
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).
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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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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