Impact of simulated central scotomas on visual search in natural scenes.
Impact of simulated central scotomas on visual search in natural scenes.
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DOI：
10.1097/opx.0b013e318267a914
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发表时间：
2012-09
期刊：
影响因子：
--
通讯作者：
Bex PJ
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文献类型：
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作者：
McIlreavy L;Fiser J;Bex PJ
在执行搜索任务时，视觉系统以与偏心率成反比的分辨率对整个视野中的信息进行编码，并部署扫视以在分辨率最高的中心凹上放置视觉上感兴趣的目标。这一系列的注视过程被眼跳般的眼球运动打断，一直持续到想要的目标被定位。中央视觉的丧失限制了目标的高空间信息的分辨能力，干扰了这种视觉搜索过程。我们用凝视相关的人工暗点来研究眼球运动对中央视野丧失的适应性。空间扭曲放置在25°正方形自然场景中的随机位置。视线相关的人工中心暗点以基于250赫兹眼镜仪的筛选率(75赫兹)更新。八名受试者在自然场景中搜索空间扭曲，并使用鼠标控制的光标指示其位置。随着中心暗点尺寸的增大，平均搜索时间增加[F(3，28)=5.27，p=0.05]，注视过程中凝视点的空间分布沿x[F(3，28)=6.33，p=0.002]和y[F(3，28)=3.32，p=0.034]轴显著增加。无论暗点大小如何，注视持续时间、眼跳大小和眼跳持续时间的眼动模式没有显著变化。在模拟的中央视力丧失后，眼球运动系统的自动适应有限。
In performing search tasks, the visual system encodes information across the visual field at a resolution inversely related to eccentricity and deploys saccades to place visually interesting targets upon the fovea where resolution is highest. The serial process of fixation, punctuated by saccadic eye movements, continues until the desired target has been located. Loss of central vision restricts the ability to resolve the high spatial information of a target, interfering with this visual search process. We investigate oculomotor adaptations to central visual field loss with gaze-contingent artificial scotomas. Spatial distortions were placed at random locations in 25° square natural scenes. Gaze-contingent artificial central scotomas were updated at the screen rate (75Hz) based on a 250Hz eyetracker. Eight subjects searched the natural scene for the spatial distortion and indicated its location using a mouse-controlled cursor. As the central scotoma size increased, the mean search time increased [F(3,28)= 5.27, p= .05] and the spatial distribution of gaze points during fixation increased significantly along the x [F(3,28)= 6.33, p= .002] and y [F(3,28)= 3.32, p= .034] axes. Oculomotor patterns of fixation duration, saccade size and saccade duration did not change significantly, regardless of scotoma size. There is limited automatic adaptation of the oculomotor system following simulated central vision loss.