The Eye Pupil Adjusts to Illusorily Expanding Holes

Abstract

Some static patterns evoke the perception of an illusory expanding central region or “hole.” We asked observers to rate the magnitudes of illusory motion or expansion of black holes, and these predicted the degree of dilation of the pupil, measured with an eye tracker. In contrast, when the “holes” were colored (including white), i.e., emitted light, these patterns constricted the pupils, but the subjective expansions were also weaker compared with the black holes. The change rates of pupil diameters were significantly related to the illusory motion phenomenology only with the black holes. These findings can be accounted for within a perceiving-the-present account of visual illusions, where both the illusory motion and the pupillary adjustments represent compensatory mechanisms to the perception of the next moment, based on shared experiences with the ecological regularities of light.

Illusory Light Drives Pupil Responses in Primates

“…The yellow stimulus was selected to match that used in the seminal human pupillometry study (Laeng & Endestad, 2012), while the cyan one was chosen to check for a possible bluish bias in this brightness illusion, as already reported in previous studies (Suzuki, Minami, Laeng, et al, 2019; Thurman et al, 2021). Finally, the magenta was retained based on a previous study with illusory expanding holes since this illusion was found to be the most effective with a magenta background (Laeng et al, 2022). Selecting these 3 colors also permitted to sample the hue space homogenously (with a distance of 120° between all 3 colors in hue space).…”

“…Another open question is whether this phenomenon plays an adaptative role or whether it is simply an epiphenomenon without any significant function. Recently, it has been proposed that the influence of cognitive/perceptual factors on pupil responses might reflect an anticipation mechanism of probable, upcoming, light stimulation that could guarantee efficient protection against light over-exposure or simply being temporarily dazzled by light, hence suggesting the possibility that this putative predictive response represents an adaptive mechanism that enhances survival in our species (Laeng et al, 2022). In this case, natural selection has likely promoted the same mechanism in a majority of species with movable pupils.…”

How the Brain Becomes the Mind: Can Thermodynamics Explain the Emergence and Nature of Emotions?

“…Disjointed sensory clues coalesce into coherent representations of a first-person, unified perspective [ 42 , 49 , 50 , 51 ]. Intelligent systems’ fundamental unity [ 27 ] permits predictive processing [ 4 ], the optimization of action repertoire between the past and the future [ 8 , 52 ], and between memory and expectation. The stationary-action principle states that the action for actual trajectories is a minimum.…”

“…Shannon refers to communication systems as the first kind of system, but intelligent systems [ 54 ], which rely on temporal computation [ 4 ], can control the future. Wissner-Gross and Freer [ 54 ] have shown a physical connection between adaptive behavior and entropy maximization.…”

“…Experimental and computational neuroscience aims to better understand the brain from the molecular to the system levels [ 1 , 2 , 3 ]—but the higher-order functions such as consciousness persistently resisted conventional approaches [ 4 ]. Although the scientific understanding of emotions has been challenging, their nature is of utmost importance in psychology, education and AI research.…”