Saccades are often directed toward a stimulus that provides useful information for observers to navigate the visual world. The quality of visual signals of a stimulus is influenced by global luminance, and the pupil constricts or dilates after a luminance increase or decrease, respectively, to optimize visual signals for further information processing. Although luminance level changes regularly in the real environment, saccades are mostly studied in the luminance‐unchanged setup. Whether pupillary responses triggered by global luminance changes modulate saccadic behavior are yet to be explored. Through varying background luminance level in an interleaved pro‐ and anti‐saccade paradigm, we investigated the modulation of pupillary luminance responses on the generation of reflexive and voluntary saccades. Subjects were instructed to either automatically look at the peripheral stimulus (pro‐saccade) or to suppress the automatic response and voluntarily look in the opposite direction from the stimulus (anti‐saccade). Level of background luminance was increased (light), decreased (dark), or unchanged (control) during the instructed fixation period. Saccade reaction time distributions of correct pro‐ and anti‐saccades in the light and dark conditions were differed significantly from those in the control condition. Moreover, the luminance condition modulated saccade kinematics, showing reduced performances in the light condition than in the control condition, particularly in pro‐saccades. Modeling results further suggested that both pupil diameter and pupil size derivative significantly modulated saccade behavior, though effect sizes were small and mainly mediated by intersubject differences. Together, our results demonstrated the influence of pupillary luminance responses on the generation of pro‐ and anti‐saccades.

中文翻译：

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瞳孔明暗反射对正视和反视的产生的影响

扫视通常是针对刺激提供的，这些刺激为观察者提供了导航视觉世界的有用信息。刺激的视觉信号的质量受整体亮度的影响，并且瞳孔分别在亮度增加或降低之后收缩或扩张，以优化视觉信号以进行进一步的信息处理。尽管在实际环境中亮度水平有规律地变化，但扫视运动大多是在亮度不变的设置中进行的。由全局亮度变化触发的瞳孔反应是否能调节眼跳行为尚待探讨。通过在交错的前扫视和反扫视范式中改变背景亮度水平，我们研究了反射性和自愿性扫视的产生对瞳孔亮度响应的调制。指示受试者要么自动观察周围刺激（前扫视），要么抑制自动应答，并自愿朝与刺激相反的方向观察（抗扫视）。在指示的定影期间内，背景亮度级别增加（亮），降低（暗）或保持不变（对照）。在明暗条件下正确的前扫视和反扫视的扫视反应时间分布与对照条件相比有显着差异。此外，亮度条件调制的扫视运动学表明，在光照条件下的性能比在控制条件下要低，特别是在前扫视条件下。建模结果进一步表明，瞳孔直径和瞳孔大小导数均显着调节了扫视行为，尽管效果的大小很小，并且主要是由受试者间的差异介导的。在一起，我们的结果证明了瞳孔亮度响应对前扫视和反扫视的产生的影响。