Towards a unified theory of microsaccadic and saccadic function: determining the significance of microsaccades for perception, cognition, and oculomotor control

扫视眼球运动-在探索视觉场景时转移我们视线的眼球运动-对视觉感知起着至关重要的多重作用。它们将高兴趣的目标带到我们视觉的中心，它们搜索和整合有关环境的一般信息，将每个视觉场景拼接在一起，它们纠正凝视错误，它们是引导我们注意力的主要机制。当我们在扫视之间注视时，我们的眼睛仍然在不断地移动，产生所谓的注视性眼球运动。关于注视过程中注视眼动对可见性的影响、注视眼动纠正注视错误的准确性以及注视眼动与注意力和其他认知过程的关系，存在着不同的观点。这些争议大多集中在历史上归因于微扫视的主要作用-最大和最快的注视眼球运动-例如在注视期间预防和恢复视力丧失以及纠正注视错误。研究人员将在人类观察者中进行眼动实验和分析，以确定微扫视对大范围刺激的可见性和注视过程中矫正眼误差的影响。在视觉探索过程中，我们大约80%的时间都在注视，因此了解注视眼动的感知效果对于理解视觉至关重要。该项目旨在扩大微扫视的范围，从具有单一或主要功能到在视觉中扮演多个非排他性角色，就像大扫视一样。因此，研究人员将着手确定微扫视是否恢复所有褪色刺激的可见性-或者仅恢复窄范围刺激的可见性-并阐明微扫视在纠正注视错误中的作用。了解微跳视如何影响可视性作为刺激特征的函数，将进一步改善视觉研究的解释，其中大部分是在固定条件下进行的。最后，确定注视位置错误后的微扫视重新瞄准固定可以帮助工程师在显示器和程序的设计中考虑这些影响，以提高操作设备时的准确性。

Saccadic eye movements -- the eye movements that shift our gaze during exploration of a visual scene --play multiple roles that are critical to visual perception. They bring high-interest targets to the center of our vision, they search and integrate general information about the environment to stitch together each visual scene, they correct gaze errors, and they are a primary mechanism to direct our attention. When we fixate our gaze between saccades, our eyes nevertheless move constantly, producing so called fixational eye movements. There is disagreement about the impact of fixational eye movements on visibility during fixation, their accuracy in correcting fixation errors, and their relationship with attention and other cognitive processes. Most of these controversies focus on the main roles historically attributed to microsaccades -the largest and fastest fixational eye movement-, such as the prevention and restoration of vision loss during fixation and the correction of fixation errors. The investigators will conduct eye movement experiments and analyses in human observers so as to determine the effects of microsaccades on the visibility of a large range of stimuli and on the correction of oculomotor error during fixation.We fixate our gaze about 80% of the time during visual exploration, and so understanding the perceptual effects of fixational eye movements is critical to understanding vision. The project aims to widen the scope of microsaccades from having a single or primary function to playing multiple non-exclusive roles in vision, in the same fashion as large saccades do. As such, the investigators will set out to determine whether microsaccades restore the visibility of all faded stimuli -or only that of a narrow range of stimuli- and to elucidate the role of microsaccades in the correction of fixation error. Understanding how microsaccades affect visibility as a function of stimulus characteristics will moreover improve the interpretation of visual studies, most of which are conducted under fixation conditions. Finally, determining that microsaccades re-target fixation after gaze position errors may help engineers to account for these effects in the design of displays and procedures to improve accuracy when operating equipment.