Pupillometry reveals perceptual differences that are tightly linked to autistic traits in typical adults

The pupil is primarily regulated by prevailing light levels, but is also modulated by perceptual and attentional factors. We measured pupil-size in typical adult humans viewing a bistable-rotating cylinder, constructed so the luminance of the front surface changes with perceived direction of rotation. In some participants, pupil diameter oscillated in phase with the ambiguous perception, more dilated when the black surface was in front. Importantly, the magnitude of oscillation predicts autistic traits of participants, assessed by the Autism-Spectrum Quotient AQ. Further experiments suggest that these results are driven by differences in perceptual styles: high AQ participants focus on the front surface of the rotating cylinder, while those with low AQ distribute attention to both surfaces in a more global, holistic style. This is the first evidence that pupillometry reliably tracks inter-individual differences in perceptual styles; it does so quickly and objectively, without interfering with spontaneous perceptual strategies.

瞳孔主要受当前光照水平调控，同时也会受到感知与注意力因素的调节。我们招募典型成年受试者，让其观看一款双稳态旋转圆柱（bistable-rotating cylinder），该装置的正面表面亮度会随受试者感知到的旋转方向发生变化，并对其瞳孔大小进行测量。部分受试者的瞳孔直径会随这种歧义感知同相位振荡：当黑色表面处于正面时，瞳孔会更为扩张。值得注意的是，这种振荡的幅度能够预测受试者的自闭症特质分数，该分数通过自闭症谱系商数（Autism-Spectrum Quotient, AQ）进行评估。后续实验表明，上述结果源于感知风格的个体差异：自闭症谱系商数得分较高的受试者会专注于旋转圆柱的正面表面，而得分较低的受试者则会以更全局、整体的方式将注意力分配至两个表面。本研究首次证明，瞳孔测量法（pupillometry）能够可靠地追踪感知风格的个体差异；该方法可快速且客观地完成检测，且不会干扰受试者自发的感知策略。