Halligan P W, Marshall J C
Rivermead Rehabilitation Centre, Oxford, UK.
Int J Neurosci. 1993 Jun;70(3-4):149-67. doi: 10.3109/00207459309000571.
Two experiments are reported on the bisection of horizontal and radial lines. In experiment 1, eighteen normal controls performed both tasks. In the horizontal orientation, approximately half the subjects produced transections displaced to the left of center and in half they were displaced to the right of center. With the radial orientation, all subjects save one bisected the line too far from the body. In experiment 2, ten patients with left neglect after unilateral right hemisphere damage performed the same two tasks. All patients showed left neglect, bisecting the horizontal lines too far to the right. Five of the patients also produced radial bisections that are outside normal limits; the predominant pattern is to bisect these lines too close to the body. The results show that severe left visuospatial neglect can co-occur with normal performance on the relative estimation of radial extents. However, in half the patients tested, performance was impaired in both orientations. The findings are set in the context of normative studies of visual anisotropy.
本文报告了两项关于水平和径向线段二等分的实验。在实验1中，18名正常对照组完成了这两项任务。在水平方向上，大约一半的受试者将线段二等分点移至中心左侧，另一半则移至中心右侧。在径向方向上，除一名受试者外，所有受试者都将线段二等分点离身体太远。在实验2中，10名单侧右半球损伤后出现左侧忽视的患者完成了相同的两项任务。所有患者均表现出左侧忽视，将水平线二等分点移至右侧太远。其中5名患者的径向二等分也超出正常范围；主要模式是将这些线段二等分点离身体太近。结果表明，严重的左侧视觉空间忽视可能与径向范围相对估计的正常表现同时出现。然而，在一半接受测试的患者中，两个方向的表现均受损。这些发现是在视觉各向异性的规范性研究背景下得出的。
