Kok Ellen M, Aizenman Avi M, Võ Melissa L-H, Wolfe Jeremy M
School of Health Professions Education, Maastricht University, Maastricht, the Netherlands.
Brigham and Women's Hospital/Harvard Medical School, Boston, MA, USA.
J Vis. 2017 Oct 1;17(12):2. doi: 10.1167/17.12.2.
People know surprisingly little about their own visual behavior, which can be problematic when learning or executing complex visual tasks such as search of medical images. We investigated whether providing observers with online information about their eye position during search would help them recall their own fixations immediately afterwards. Seventeen observers searched for various objects in "Where's Waldo" images for 3 s. On two-thirds of trials, observers made target present/absent responses. On the other third (critical trials), they were asked to click twelve locations in the scene where they thought they had just fixated. On half of the trials, a gaze-contingent window showed observers their current eye position as a 7.5° diameter "spotlight." The spotlight "illuminated" everything fixated, while the rest of the display was still visible but dimmer. Performance was quantified as the overlap of circles centered on the actual fixations and centered on the reported fixations. Replicating prior work, this overlap was quite low (26%), far from ceiling (66%) and quite close to chance performance (21%). Performance was only slightly better in the spotlight condition (28%, p = 0.03). Giving observers information about their fixation locations by dimming the periphery improved memory for those fixations modestly, at best.
人们对自身的视觉行为了解之少，令人惊讶。而在学习或执行复杂的视觉任务（如搜索医学图像）时，这可能会带来问题。我们研究了在搜索过程中向观察者提供有关其眼睛位置的在线信息，是否会帮助他们在之后立即回忆起自己的注视点。17名观察者在“威利在哪里”图像中搜索各种物体，持续3秒。在三分之二的试验中，观察者做出目标是否存在的反应。在另外三分之一（关键试验）中，他们被要求在场景中点击十二个他们认为自己刚刚注视过的位置。在一半的试验中，一个注视点相关窗口向观察者显示他们当前的眼睛位置，呈现为一个直径7.5°的“聚光灯”。聚光灯“照亮”所有被注视的内容，而显示屏的其余部分仍然可见，但较暗。表现通过以实际注视点为中心和以报告的注视点为中心的圆的重叠程度来量化。重复之前的研究，这种重叠程度相当低（26%），远未达到上限（66%），且非常接近随机表现（21%）。在聚光灯条件下表现仅略有改善（28%，p = 0.03）。通过使周边区域变暗来向观察者提供关于他们注视位置的信息，充其量只能适度提高对这些注视点的记忆。
