Separable pupillary signatures of perception and action during perceptual multistability
Abstract
The pupil provides a rich, non-invasive measure of the neural bases of perception and cognition, and has been of particular value in uncovering the role of arousal-linked neuromodulation, which alters both cortical processing and pupil size. But pupil size is subject to a multitude of influences, which complicates unique interpretation. We measured pupils of observers experiencing perceptual multistability -- an ever-changing subjective percept in the face of unchanging but inconclusive sensory input. In separate conditions the endogenously generated perceptual changes were either task-relevant or not, allowing a separation between perception-related and task-related pupil signals. Perceptual changes were marked by a complex pupil response that could be decomposed into two components: a dilation tied to task execution and plausibly indicative of an arousal-linked noradrenaline surge, and an overlapping constriction tied to the perceptual transient and plausibly a marker of altered visual cortical representation. Constriction, but not dilation, amplitude systematically depended on the time interval between perceptual changes, possibly providing an overt index of neural adaptation. These results show that the pupil provides a simultaneous reading on interacting but dissociable neural processes during perceptual multistability, and suggest that arousal-linked neuromodulator release shapes action but not perception in these circumstances.
Data availability
The raw data associated with this study are available from datadryad.org (https://doi.org/10.5061/dryad.41ns1rncp)Analysis code associated with this study is available from GitHub (https://github.com/janbrascamp/Pupils_during_binocular_rivalry)
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Data from: Separable pupillary signatures of perception and action during perceptual multistabilityDryad Digital Repository, doi:10.5061/dryad.41ns1rncp.
Article and author information
Author details
Funding
No external funding was received for this work.
Reviewing Editor
- Miriam Spering, The University of British Columbia, Canada
Ethics
Human subjects: Informed consent, and consent to publish, was obtained, and all research was approved by Michigan State University IRB, and executed in accordance with the Michigan State University IRB guidelines. The MSU IRB protocol number associated with this work is IRB# 17-996.
Version history
- Received: December 30, 2020
- Preprint posted: January 24, 2021 (view preprint)
- Accepted: August 11, 2021
- Accepted Manuscript published: August 11, 2021 (version 1)
- Version of Record published: August 20, 2021 (version 2)
Copyright
© 2021, Brascamp 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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