Assessment of left unilateral spatial neglect using illusory figures

单侧空间忽略是指对脑损伤相对侧的新的或有意义的刺激不能报告、反应或定向（Heilman，1979）。传统上，单侧空间忽略是通过使用几种视觉探索测试来评估的，例如线取消任务或线平分任务。本研究的目的是评估新的评估技术，利用视错觉。本研究采用Wundt-Jastrow错觉图形进行了三个实验，以探讨这种类型的测试的临床应用，并评估左侧单侧空间忽略患者的认知功能。实验一，对胼胝体损伤患者进行了测试，并使用Wundt-Jastrow错觉图形阐明了患者认知功能的注意方面。在接下来的实验中，我们记录了这名患者在测试过程中的眼球运动，他的目光迅速移动到图形的右侧，而没有实质性的搜索。为了研究精确的眼球注视模式，我们使用线平分与结构化呈现方法进行了第三个实验。结果表明，患者主要从刺激的右端点推断线条长度。通过这一系列的实验，提示单侧空间忽视患者对虚幻图形的反应可能揭示了对右侧刺激的过度注意。进一步的实验证实，代表性方面的赤字也影响到这些结果。

Unilateral spatial neglect is the failure to report, respond, or orient to novel or meaningful stimuli presented to the side opposite a brain lesion (Heilman, 1979). Traditionally unilateral spatial neglect is evaluated by using several visual exploration tests, such as the line cancellation task, or the line bisection task. The aim of the present study was to evaluate the new assessment technique using optical illusion. We performed three experiments employing the Wundt-Jastrow illusory figures to investigate the clinical application of this type of test and to evaluate the cognitive functions of the patients with left unilateral spatial neglect In the first experiment, the test was given to the patient with callosal lesion and clarified the attentional aspect of the cognitive function of the patient by using the Wundt-Jastrow Illusory figures. In the next experiment, we recorded the eye movement of this patient during the test His gaze quickly moved to the right side of the figure without substantial leftward search, To investigate precise eye fixation patterns, we performed the third experiment by using line bisection with structured presentation method. The results revealed that the patients were inferred line length mainly from the right endpoint of the stimulus. Through this series of experiments, it implies that the response to the illusory figure in patients with unilateral spatial neglect may reveal overattention to the right side of stimulus. Additional experiments confirmed that representational aspect of the deficit was also affected to these results.