Heilman K M, Valenstein E
Ann Neurol. 1979 Feb;5(2):166-70. doi: 10.1002/ana.410050210.
If patients with left-sided hemispatial neglect bisect lines incorrectly because hemianopia or sensory hemiinattention prevents them from seeing how far the line extends to the left, a strategy that ensures their seeing the left side of the line in their normal field should improve performance. If patients have hemispatial hypokinesia, moving the line toward the normal half of body space should improve performance. Six patients with left-sided neglect from right hemisphere infarctions were required to identify a letter at either the right or the left end of a line before bisecting that line. The task was given with the lines placed at either the right, the center, or the left of the body midline. Performance in trials when subjects were required to look to the left before bisecting a line did not differ from when they were required to look right. Performance was significantly better when the line was placed to the right side of the body than to the left. These observations support the hypothesis that patients with hemispatial neglect have hemispatial hypokinesia. An alternative hypothesis is that these subjects had a hemispatial memory defect. Although they saw the left side of the line in their normal field, they were incapable of forming a stable trace and performed as if they did not see the left side of the line.
如果左侧半侧空间忽视患者错误地平分线段是因为偏盲或感觉性半侧注意力不集中使他们无法看到线段向左延伸的长度，那么一种确保他们在正常视野中看到线段左侧的策略应该能改善表现。如果患者有半侧空间运动不能，将线段移向身体空间正常的一侧应该能改善表现。六名因右侧半球梗死导致左侧忽视的患者在平分线段之前需要识别线段右端或左端的一个字母。该任务在将线段放置于身体中线右侧、中心或左侧的情况下进行。当要求受试者在平分线段前向左看时的试验表现与要求他们向右看时的表现没有差异。当线段放置在身体右侧时的表现明显优于放置在左侧时。这些观察结果支持了半侧空间忽视患者存在半侧空间运动不能的假说。另一种假说是这些受试者存在半侧空间记忆缺陷。尽管他们在正常视野中看到了线段的左侧，但他们无法形成稳定的痕迹，表现得就好像没有看到线段的左侧一样。
