Psychological Sciences Research Institute, Université catholique de Louvain, Place Cardinal Mercier, 10, Louvain-la-Neuve, Louvain, Belgium.
Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, 33076, Bordeaux, France.
Psychon Bull Rev. 2022 Oct;29(5):1844-1853. doi: 10.3758/s13423-022-02094-0. Epub 2022 Apr 6.
The pupil light response is more than a pure reflexive mechanism that reacts to the amount of light entering the eye. The pupil size may also react to the luminance of objects lying in the visual periphery, revealing the locus of covert attention. In the present study, we took advantage of this response to study the spatial coding of abstract concepts with no physical counterpart: numbers. The participants' gaze was maintained fixed in the middle of a screen whose left and right parts were dark or bright, and variations in pupil size were recorded during an auditory number comparison task. The results showed that small numbers accentuated pupil dilation when the darker part of the screen was on the left, while large numbers accentuated pupil dilation when the darker part of the screen was on the right. This finding provides direct evidence for covert attention shifts on a left-to-right oriented mental spatial representation of numbers. From a more general perspective, it shows that the pupillary response to light is subject to modulation from spatial attention mechanisms operating on mental contents.
瞳孔光反应不仅仅是一种对进入眼睛的光量做出反应的纯反射机制。瞳孔大小也可能对位于视觉外围的物体的亮度做出反应，从而揭示隐蔽注意力的位置。在本研究中，我们利用这种反应来研究没有物理对应物的抽象概念的空间编码：数字。参与者的目光保持在屏幕中间固定，屏幕的左右两侧为暗或亮，在听觉数字比较任务期间记录瞳孔大小的变化。结果表明，当屏幕的较暗部分在左侧时，较小的数字会使瞳孔扩张加剧，而当屏幕的较暗部分在右侧时，较大的数字会使瞳孔扩张加剧。这一发现为在数字的左右方向的心理空间表示上的隐蔽注意力转移提供了直接证据。从更广泛的角度来看，它表明对光的瞳孔反应受到在心理内容上运作的空间注意机制的调制。
