Sint Maartenskliniek Research, Development and Education, Nijmegen, The Netherlands.
Cortex. 2010 May;46(5):602-12. doi: 10.1016/j.cortex.2009.06.004. Epub 2009 Jun 13.
Asymmetry in performance and an association with non-lateralized attention are often mentioned as two important aspects of the clinical manifestation of visuospatial neglect. Both these aspects were investigated in 21 left (LH) and 24 right hemisphere (RH) stroke patients and in 20 healthy subjects. The letter and star cancellation subtests of the Behavioural Inattention Task (BIT) and a computerized visual reaction time task (CVRT) with stimuli presented either left, central or right in extrapersonal space were administered. In LH patients, the calculation of BIT asymmetry scores allowed a better distinction between patients with and without neglect than raw omission scores. However, in RH patients, raw and asymmetry scores led to similar classifications. In the CVRT, raw and asymmetry scores for the number of omissions also produced identical classifications. Thus, the computation of asymmetry scores for omissions did not substantially refine the diagnosis of neglect. On the other hand, more patients were classified as neglect patients by using CVRT reaction time (RT) asymmetry scores than by using BIT or CVRT omission scores. Ipsilesional RT's were chosen as a measure of general, non-lateralized attention. The ipsilesional RT's of the LH and RH patients did not differ from the healthy subjects' lateral RT's. However, within the RH group, patients with both RT asymmetries and BIT scores above cut-off level showed longer ipsilesional RT's than patients with defective RT asymmetries but normal BIT scores. This supports the idea of an interaction between lateralized and non-lateralized attentional components in neglect, in which the presence of general attentional deficits exacerbates the severity of neglect symptoms. RT tasks may contribute to the detection of asymmetries in visuospatial attention in patients with subclinical neglect symptoms, who might compensate for their lateralized deficit in paper-and-pencil tasks employing intact general attention.
表现的不对称性和与非侧化注意的关联常被提及为视觉空间忽略的临床表现的两个重要方面。这两个方面都在 21 名左侧（LH）和 24 名右侧（RH）中风患者以及 20 名健康受试者中进行了研究。使用行为疏忽任务（BIT）的字母和星号取消子测试以及在体外空间中呈现左侧、中央或右侧刺激的计算机化视觉反应时间任务（CVRT）进行了测试。在 LH 患者中，与原始遗漏分数相比，BIT 不对称分数的计算可更好地区分有无忽略的患者。然而，在 RH 患者中，原始和不对称分数导致了类似的分类。在 CVRT 中，遗漏的原始和不对称分数也产生了相同的分类。因此，遗漏的不对称分数的计算并未实质上改进忽略的诊断。另一方面，与使用 BIT 或 CVRT 遗漏分数相比，使用 CVRT 反应时间（RT）不对称分数对更多患者进行了忽略患者的分类。同侧 RT 被选为一般非侧化注意的度量。LH 和 RH 患者的同侧 RT 与健康受试者的外侧 RT 没有差异。然而，在 RH 组中，具有 RT 不对称和 BIT 得分均高于临界值的患者的同侧 RT 比具有缺陷 RT 不对称但正常 BIT 得分的患者长。这支持了在忽略中存在侧化和非侧化注意成分之间相互作用的观点，其中一般注意缺陷的存在会加剧忽略症状的严重程度。RT 任务可能有助于检测具有亚临床忽略症状的患者在视觉空间注意力方面的不对称性，这些患者可能会在使用完整的一般注意力的纸笔任务中补偿其侧化缺陷。
