Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
Brain Res. 2011 Jan 7;1367:265-77. doi: 10.1016/j.brainres.2010.10.022. Epub 2010 Oct 13.
Simultanagnosia is a disorder of visual attention, defined as an inability to see more than one object at once. It has been conceived as being due to a constriction of the visual "window" of attention, a metaphor that we examine in the present article. A simultanagnosic patient (SL) and two non-simultanagnosic control patients (KC and ES) described social scenes while their eye movements were monitored. These data were compared to a group of healthy subjects who described the same scenes under the same conditions as the patients, or through an aperture that restricted their vision to a small portion of the scene. Experiment 1 demonstrated that SL showed unusually low proportions of fixations to the eyes in social scenes, which contrasted with all other participants who demonstrated the standard preferential bias toward eyes. Experiments 2 and 3 revealed that when healthy participants viewed scenes through a window that was contingent on where they looked (Experiment 2) or where they moved a computer mouse (Experiment 3), their behavior closely mirrored that of patient SL. These findings suggest that a constricted window of visual processing has important consequences for how simultanagnosic patients explore their world. Our paradigm's capacity to mimic simultanagnosic behaviors while viewing complex scenes implies that it may be a valid way of modeling simultanagnosia in healthy individuals, providing a useful tool for future research. More broadly, our results support the thesis that people fixate the eyes in social scenes because they are informative to the meaning of the scene.
同时失认症是一种视觉注意力障碍，表现为一次无法看到多个物体。它被认为是由于注意力的视觉“窗口”收缩所致，我们在本文中对此进行了探讨。一位同时失认症患者 (SL) 和两位非同时失认症对照患者 (KC 和 ES) 在描述社交场景时，其眼球运动被监测。这些数据与一组健康受试者进行了比较，健康受试者在与患者相同的条件下或通过限制其视野到场景的一小部分的孔径来描述相同的场景。实验 1 表明，SL 在社交场景中对眼睛的注视比例异常低，与所有其他参与者形成鲜明对比，后者表现出对眼睛的标准偏好偏差。实验 2 和 3 表明，当健康参与者通过一个取决于他们注视位置的窗口（实验 2）或他们移动计算机鼠标的位置的窗口（实验 3）观看场景时，他们的行为与患者 SL 的行为非常相似。这些发现表明，视觉处理的窗口收缩对同时失认症患者如何探索他们的世界有重要影响。我们的范式在观看复杂场景时能够模拟同时失认症行为，这意味着它可能是在健康个体中模拟同时失认症的一种有效方法，为未来的研究提供了有用的工具。更广泛地说，我们的结果支持这样一个论点，即人们在社交场景中注视眼睛是因为它们对场景的意义有信息。
