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 participants with higher Autism-Spectrum Quotient (AQ), consistent with a local style of perception, 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.

Attention cueing in rivalry: insights from pupillometry

“…This is not the first case where we find that pupillary responses are independent of physical luminance and yet inconsistent with perceptual judgments (Benedetto and Binda, 2016; Turi et al, 2018; Pome et al, 2020; Tortelli et al, 2020, 2021). These inconsistencies were generally explained by calling decisional factors into the picture, as these may bias or add variability to perceptual reports while leaving pupil size unaffected (Tortelli et al, 2021). That contextual factors other than physical luminance affect pupil size and perception similarly but independently – if it proves recurrent and reliable across paradigms – might call for an updated model of pupil control.…”

“…However, light responses are modulated by attention, brightness illusions and contextual processing (Laeng et al, 2012; Binda and Murray, 2015; Mathot, 2018) indicating that the subcortical circuit is fed with cortical signals (Binda and Gamlin, 2017) that represent effective stimulus strength. As long as stimuli are tagged with different luminance, pupil diameter can be used to accurately and precisely track attention in space (Binda et al, 2013; Mathot et al, 2013; Naber et al, 2013) and perceptual alternations over time (Lowe and Ogle, 1966; Einhauser et al, 2008; Fahle et al, 2011; Naber et al, 2011; Turi et al, 2018; Tortelli et al, 2021). Here we exploited this strategy and used luminance to tag pupil responses to stimuli rivaling in perception.…”

Attention Cueing in Rivalry: Insights from Pupillometry

“…This is not the first case where we find that the pupillary responses are independent of physical luminance and yet inconsistent with perceptual judgments (Benedetto and Binda, 2016;Turi et al, 2018;Pome et al, 2020;Tortelli et al, 2021a,b). These inconsistencies were generally explained by calling decisional factors into the picture, as these may bias or add variability to perceptual reports while leaving pupil size unaffected (Tortelli et al, 2021b). That contextual factors other than physical luminance affect pupil size and perception similarly but independently, if it proves recurrent and reliable across paradigms, might call for an updated model of pupil control.…”

“…However, light responses are modulated by saliency, attention, brightness illusions and contextual processing (Laeng et al, 2012;Binda and Murray, 2015;Wang and Munoz, 2015;Mathôt, 2018) indicating that the subcortical circuit is fed with cortical signals (Binda and Gamlin, 2017) that represent effective stimulus strength. As long as stimuli are tagged with different luminance, pupil diameter can be used to accurately and precisely track attention in space (Binda et al, 2013;Mathôt et al, 2013;Naber et al, 2013) and perceptual alternations over time (Lowe and Ogle, 1966;Einhäuser et al, 2008;Fahle et al, 2011;Naber et al, 2011;Turi et al, 2018;Tortelli et al, 2021b). Here, we exploited this strategy and used luminance to tag pupil responses to stimuli rivaling in perception (for an alternative approach that did not rely on luminance tagging, see Brascamp et al, 2021) .…”

The amplitude of fNIRS hemodynamic response in the visual cortex unmasks autistic traits in typically developing children

“…Moreover, these data reinforce the concept that THb changes could provide richer discriminative information for classifying between typically developing children and ASD subjects 54 . A tentative explanation of reduced HDR in children with stronger autistic traits might be found in the difference of perceptual styles in the general population 77,78 : the preference for focusing on local details vs. the global stimulus configuration, indeed, is a defining feature of ASD 79 and locally centered perception could be less effective in activating neural circuits of visual cortex. Interestingly, a recent study established a vascular link to ASD, showing early dysfunction of endothelial cells and impaired endothelium-dependent vasodilation in a mouse model of 16p11.2 deletion 80 .…”