Dipartimento di Scienze della Cognizione e della Formazione, University of Trento, Italy.
J Clin Exp Neuropsychol. 2011 Feb;33(2):249-56. doi: 10.1080/13803395.2010.511150.
The Judgment of Line Orientation Test (JLOT) is considered a valid task for the assessment of visuospatial perception, and, for this reason, it is also considered to be a sensitive tool able to discriminate between right-hemisphere-damaged (RHD) patients and left-hemisphere-damaged (LHD) patients. In contrast with this view, we report evidence that the greater impairment in JLOT usually shown by RHD patients is unrelated to the supposed JLOT effectiveness in measuring visuospatial judgment ability and to the putative dominant role of the right hemisphere in visuospatial processing. JLOT is characterized by a left-right structural asymmetry (i.e., left-side lines are easier to judge) that seriously undermines the test validity: This asymmetry interacts with ipsilesional attentional biases of brain-damaged patients and affects their performance. Results obtained with a JLOT version composed of both the original items and their mirror-reversed versions clearly indicate that the cognitive functions tested by the JLOT are distributed across the two hemispheres: LHD and RHD patients did not differ from each other or from their matched controls when their performances were compared on this balanced JLOT version. Impaired performances of either RHD or LHD patients were found only when performances in original and mirror-reversed items were considered separately. This suggests that the original JLOT cannot assess visuospatial perception independently from attentional biases. The test can be a powerful clinical tool, as long as both original and mirror-reversed items are used, and the standard scoring method is replaced by the evaluation of the individual lines of stimulus pairs.
线定向测验 (JLOT) 被认为是评估视空间感知的有效任务，因此，它也被认为是一种敏感的工具，能够区分右脑损伤 (RHD) 患者和左脑损伤 (LHD) 患者。与这种观点相反，我们报告的证据表明，RHD 患者在 JLOT 中通常表现出更大的损伤与假设的 JLOT 测量视空间判断能力的有效性以及右半球在视空间处理中的假定主导作用无关。JLOT 具有左右结构不对称性（即左侧线条更容易判断），这严重破坏了测试的有效性：这种不对称性与脑损伤患者的同侧注意偏向相互作用，并影响他们的表现。使用由原始项目及其镜像反转版本组成的 JLOT 版本获得的结果清楚地表明，JLOT 测试的认知功能分布在两个半球中：当比较 LHD 和 RHD 患者在这个平衡的 JLOT 版本上的表现时，他们彼此之间以及与他们的匹配对照组之间没有差异。只有当分别考虑原始和镜像反转项目的表现时，才会发现 RHD 或 LHD 患者的受损表现。这表明原始的 JLOT 不能独立于注意偏向来评估视空间感知。只要使用原始和镜像反转项目，并采用评估刺激对个体线条的方法替代标准评分方法，该测试就可以成为一种强大的临床工具。
