ABSTRACT

Introduction: Personal neglect (PN) refers to a form of hemi-inattention toward the contralesional body space and it usually occurs following a right brain lesion. Recent studies suggest that PN indicates a disorder of body representation. Specifically, patients with PN show difficulties in identifying differences between left and right hands and have an altered visuospatial body map, which is associated with disrupted mental body representations. However, the metric representation of the body, and in particular the hands, has not been systematically addressed in patients showing this form of neglect.

Method: In the present study, we have investigated this representation by testing the perceived hands’ width of 11 hemiplegic patients with right hemisphere cerebral lesions (5 with PN) and 12 healthy controls on a judgment of passability task. Patients and controls were asked to imagine inserting their hand (left and right) through a series of vertical apertures of different sizes and to judge whether their hand could fit through. Due to the heterogeneity of the data, both parametric and non-parametric approaches were used. Furthermore, additional single-case analyses were conducted.

Results: Study findings showed that patients with PN showed a significant underestimation of the left hand compared with their right hand. In contrast, whilst the right hand was equally distorted in both patients’ groups, the hemiplegic patients with no evidence of PN tended to perceive the affected hand as larger than their ipsilesional one.

Conclusions: In line with the literature, our findings confirm an underlying distorted body representation following right brain damage. However, for the first time, we report both a quantitative and qualitative difference in impact of hemiplegia and PN on body representation of the contralesional body space.

摘要

简介：人身疏忽（PN）是指对对侧身体空间的半注意力不集中的一种形式，通常发生在右脑病变之后。最近的研究表明，PN指示身体代表疾病。具体而言，PN患者在识别左手和右手之间的差异时表现出困难，并且视觉空间的身体图谱发生了变化，这与精神身体表征的破坏有关。然而，对于表现出这种忽视形式的患者，尚未系统地解决身体，特别是手的度量表示。

方法：在本研究中，我们通过测试11名右半球大脑病变的偏瘫患者（5名PN）和12名健康对照的可感知手的宽度，以判断是否通过任务。患者和对照组被要求想象将他们的手（左右）插入一系列不同大小的垂直孔中，并判断他们的手是否适合。由于数据的异质性，因此使用了参数方法和非参数方法。此外，还进行了其他单例分析。

结果：研究结果表明，与右手相比，PN患者左手明显偏低。相比之下，尽管两组患者的右手都同样变形，但没有PN证据的偏瘫患者往往会感觉到受影响的手比同病的手大。

结论：根据文献，我们的发现证实了右脑损伤后潜在的身体扭曲。但是，我们首次报道了偏瘫和PN对对侧人体空间的身体表征的影响在数量和质量上都存在差异。