Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany.
Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany.
Elife. 2022 Sep 9;11:e78106. doi: 10.7554/eLife.78106.
High-acuity foveal processing is vital for human vision. Nonetheless, little is known about how the preparation of large-scale rapid eye movements (saccades) affects visual sensitivity in the center of gaze. Based on findings from passive fixation tasks, we hypothesized that during saccade preparation, foveal processing anticipates soon-to-be fixated visual features. Using a dynamic large-field noise paradigm, we indeed demonstrate that defining features of an eye movement target are enhanced in the pre-saccadic center of gaze. Enhancement manifested as higher Hit Rates for foveal probes with target-congruent orientation and a sensitization to incidental, target-like orientation information in foveally presented noise. Enhancement was spatially confined to the center of gaze and its immediate vicinity, even after parafoveal task performance had been raised to a foveal level. Moreover, foveal enhancement during saccade preparation was more pronounced and developed faster than enhancement during passive fixation. Based on these findings, we suggest a crucial contribution of foveal processing to trans-saccadic visual continuity: Foveal processing of saccade targets commences before the movement is executed and thereby enables a seamless transition once the center of gaze reaches the target.
高敏度中央凹处理对人类视觉至关重要。然而，对于准备大范围快速眼球运动（扫视）如何影响注视中心的视觉灵敏度，我们知之甚少。基于被动注视任务的发现，我们假设在扫视准备期间，中央凹处理会预测即将注视的视觉特征。我们确实使用动态大视野噪声范式证明，在扫视前的注视中心，眼动目标的定义特征得到了增强。增强表现为具有目标一致方向的中央凹探测的更高击中率，以及对中央凹呈现噪声中偶然出现的、类似目标的方向信息的敏感性。增强在空间上局限于注视中心及其附近区域，即使在旁中心任务表现提高到中央凹水平之后也是如此。此外，扫视准备期间的中央凹增强比被动注视期间的增强更明显且发展更快。基于这些发现，我们建议中央凹处理对跨扫视视觉连续性有重要贡献：扫视目标的中央凹处理在运动执行之前开始，从而使注视中心到达目标时能够实现无缝过渡。
