Neuroimaging Laboratory, Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Via Ardeatina 306, 00179, Rome, Italy.
MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK.
Brain Imaging Behav. 2022 Feb;16(1):211-218. doi: 10.1007/s11682-021-00493-w. Epub 2021 Jul 30.
A typical consequence of stroke in the right hemisphere is unilateral spatial neglect. Distinct forms of neglect have been described, such as space-based (egocentric) and object-based (allocentric) neglect. However, the relationship between these two forms of neglect is still far from being understood, as well as their neural substrates. Here, we further explore this issue by using voxel lesion symptoms mapping (VLSM) analyses on a large sample of early subacute right-stroke patients assessed with the Apples Cancellation Test. This is a sensitive test that simultaneously measures both egocentric and allocentric neglect. Behaviourally, we found no correlation between egocentric and allocentric performance, indicating independent mechanisms supporting the two forms of neglect. This was confirmed by the VLSM analysis that pointed out a link between a damage in the superior longitudinal fasciculus and left egocentric neglect. By contrast, no association was found between brain damage and left allocentric neglect. These results indicate a higher probability to observe egocentric neglect as a consequence of white matter damages in the superior longitudinal fasciculus, while allocentric neglect appears more "globally" related to the whole lesion map. Overall, these findings on early subacute right-stroke patients highlight the role played by white matter integrity in sustaining attention-related operations within an egocentric frame of reference.
中风右半球的一个典型后果是单侧空间忽略。已经描述了不同形式的忽略，例如基于空间的（自我中心的）和基于物体的（非自我中心的）忽略。然而，这两种形式的忽略之间的关系仍然远未被理解，以及它们的神经基础。在这里，我们通过使用 VLSM 分析对大量早期亚急性右卒中患者进行研究，进一步探讨了这个问题，这些患者使用苹果取消测试进行评估。这是一种敏感的测试，可以同时测量自我中心和非自我中心的忽略。行为上，我们发现自我中心和非自我中心表现之间没有相关性，表明支持这两种忽略的机制是独立的。VLSM 分析证实了这一点，该分析指出在左上纵束损伤与左侧自我中心忽略之间存在联系。相比之下，大脑损伤与左侧非自我中心忽略之间没有关联。这些结果表明，在左上纵束的白质损伤中，更有可能观察到自我中心忽略，而非自我中心忽略似乎与整个病变图更“整体”相关。总的来说，这些对早期亚急性右卒中患者的发现强调了白质完整性在维持自我中心参考框架内的注意力相关操作中的作用。
