Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892.
Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892
eNeuro. 2023 Oct 18;10(10). doi: 10.1523/ENEURO.0005-23.2023. Print 2023 Oct.
Similar to a camera aperture, pupil size adjusts to the surrounding luminance. Unlike a camera, pupil size is additionally modulated both by stimulus properties and by cognitive processes, including attention and arousal, though the interdependence of these factors is unclear. We hypothesized that different stimulus properties interact to jointly modulate pupil size while remaining independent from the impact of arousal. We measured pupil responses from human observers to equiluminant stimuli during a demanding rapid serial visual presentation (RSVP) task at fixation and tested how response amplitude depends on contrast, spatial frequency, and reward level. We found that under constant luminance, unattended stimuli evoke responses that are separable from changes caused by general arousal or attention. We further uncovered a double-dissociation between task-related responses and stimulus-evoked responses, suggesting that different sources of pupil size modulation are independent of one another. Our results shed light on neural pathways underlying pupillary response.
类似于相机光圈，瞳孔大小会根据周围的亮度进行调整。与相机不同的是，瞳孔大小除了受到刺激特性的调节外，还受到认知过程的调节，包括注意力和觉醒，尽管这些因素的相互依赖性尚不清楚。我们假设不同的刺激特性相互作用，共同调节瞳孔大小，同时与觉醒的影响无关。我们在注视时对人类观察者进行了测量，在要求很高的快速序列视觉呈现 (RSVP) 任务中测量了瞳孔对等亮度刺激的反应，并测试了反应幅度如何取决于对比度、空间频率和奖励水平。我们发现，在恒定亮度下，未被注意的刺激会引起与一般觉醒或注意力引起的变化可区分的反应。我们进一步揭示了与任务相关的反应和由刺激引起的反应之间的双重分离，这表明不同的瞳孔大小调节源彼此独立。我们的研究结果为瞳孔反应的神经通路提供了线索。
