Objective pupillometry shows that perceptual styles covary with autistic-like personality traits
Abstract
We measured the modulation of pupil-size (in constant lighting) elicited by observing transparent surfaces of black and white moving dots, perceived as a cylinder rotating about its vertical axis. The direction of rotation was swapped periodically by flipping stereo-depth of the two surfaces. Pupil size modulated in synchrony with the changes in front-surface color (dilating when black). The magnitude of pupillary modulation was larger for human participants with higher Autism-Spectrum Quotient (AQ), consistent with a local perceptual style , with attention focused on the front surface. The modulation with surface color, and its correlation with AQ, was equally strong when participants passively viewed the stimulus. No other indicator, including involuntary pursuit eye-movements, covaried with AQ. These results reinforce our previous report with a similar bistable stimulus (Turi, Burr, & Binda, 2018), and go on to show that bistable illusory motion is not necessary for the effect, or its dependence on AQ.
Data availability
Experimental data have been uploaded to Zenodo at the following doi: 10.5281/zenodo.4486576
Article and author information
Author details
Funding
H2020 European Research Council (801715)
- Paola Binda
H2020 European Research Council (832813)
- David Charles Burr
Ministero dell'Istruzione, dell'Università e della Ricerca (MISMATCH)
- Paola Binda
Ministero dell'Istruzione, dell'Università e della Ricerca (R182E5PNC7)
- Paola Binda
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Experimental procedures were approved by the regional ethics committee [Comitato Etico Pediatrico Regionale-Azienda Ospedaliero-Universitaria Meyer-Firenze (FI)] and are in accordance with the declaration of Helsinki. Participants gave their written informed consent.
Copyright
© 2021, Tortelli 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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