Previous studies show that the amplitude of pupillary light response (PLR) depends on the corneal flux density (CFD), which is the product of stimulus area by luminance. However, the contribution of CFD has been investigated only when the stimulus was centered on the fovea, whereas perceived luminance to pupillary response would reduce with stimulus eccentricity. Additionally, it has been shown recently that attentional state modulates pupillary response. In this study, we aimed to clarify the complete mechanisms of PLR by manipulating the stimulus size, eccentricity, luminance, and the participants' attentional states. We focused on four indices to examine PLR, that is, pupillary latency (PL), maximum constriction velocity (MCV), maximum constriction (MC), and mean pupil change (MPC). Results showed that PL was a function of CFD, whereas MCV, MC, and MPC were functions of both CFD and stimulus eccentricity. Furthermore, the magnitude of effect due to stimulus eccentricity for MCV and MC was different from that for MPC. These results provided new evidence that the different processing systems in PLR existed.

中文翻译：

---

刺激大小，偏心率，亮度和注意力对同心刺激检查的瞳孔光反应的影响。

先前的研究表明，瞳孔光响应（PLR）的幅度取决于角膜通量密度（CFD），该角膜通量密度是刺激面积与亮度的乘积。然而，仅当刺激以中央凹为中心时，才研究了CFD的贡献，而对瞳孔反应的感知亮度会随着刺激的偏心而降低。另外，最近已经显示出注意力状态调节瞳孔反应。在这项研究中，我们旨在通过操纵刺激的大小，偏心率，亮度和参与者的注意状态来阐明PLR的完整机制。我们集中于四个指标来检查PLR，即瞳孔潜伏期（PL），最大收缩速度（MCV），最大收缩（MC）和平均瞳孔变化（MPC）。结果表明PL是CFD的函数，而MCV是 MC和MPC都是CFD和刺激性偏心率的函数。此外，由于MCV和MC的刺激性偏心所引起的影响程度不同于MPC。这些结果提供了新的证据，证明PLR中存在不同的处理系统。