Effects of pupillary light and darkness reflex on the generation of pro‐ And anti‐saccades. (27th December 2020)

• Record Type: Journal Article
• Authors: Cherng, Yih‐Giun; Crevecoeur, Frédéric; Wang, Chin‐An
• Is Part Of: European journal of neuroscience. Volume 53:Number 6(2021)
• Page Start: 1769
• Page End: 1782
• Publication Date: 2020-12-27
• Subjects: anti‐saccade -- global luminance -- pupillometry -- superior colliculus; Nervous system -- Periodicals; 612.8
• DOI: 10.1111/ejn.15083
• Languages: English
• ISSNs: 0953-816X

Abstract

Abstract: 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. Abstract : Through varying background luminance level in the pro‐ and anti‐saccade paradigm, we investigated the modulation of pupillary luminance responses on the generation of reflexive and voluntary saccades. SRT distributions in the light and dark conditions differed significantly from those in the control condition. Pupillary luminance changes also modulated saccade kinematics. Our results demonstrated that pupil size adjusted to global luminance changes affects pro‐ and anti‐saccade generation.