Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
Brain. 2011 Oct;134(Pt 10):3094-105. doi: 10.1093/brain/awr050. Epub 2011 Jun 17.
The role of the anterior temporal lobes in cognition and language has been much debated in the literature over the last few years. Most prevailing theories argue for an important role of the anterior temporal lobe as a semantic hub or a place for the representation of unique entities such as proper names of peoples and places. Lately, a few studies have investigated the role of the most anterior part of the left anterior temporal lobe, the left temporal pole in particular, and argued that the left anterior temporal pole is the area responsible for mapping meaning on to sound through evidence from tasks such as object naming. However, another recent study indicates that bilateral anterior temporal damage is required to cause a clinically significant semantic impairment. In the present study, we tested these hypotheses by evaluating patients with acute stroke before reorganization of structure-function relationships. We compared a group of 20 patients with acute stroke with anterior temporal pole damage to a group of 28 without anterior temporal pole damage matched for infarct volume. We calculated the average percent error in auditory comprehension and naming tasks as a function of infarct volume using a non-parametric regression method. We found that infarct volume was the only predictive variable in the production of semantic errors in both auditory comprehension and object naming tasks. This finding favours the hypothesis that left unilateral anterior temporal pole lesions, even acutely, are unlikely to cause significant deficits in mapping meaning to sound by themselves, although they contribute to networks underlying both naming and comprehension of objects. Therefore, the anterior temporal lobe may be a semantic hub for object meaning, but its role must be represented bilaterally and perhaps redundantly.
在过去的几年里，文献中对前颞叶在认知和语言中的作用进行了大量的讨论。大多数主流理论认为，前颞叶作为语义枢纽或独特实体（如人名和地名）的代表具有重要作用。最近，一些研究调查了左前颞叶最前部（特别是左颞极）的作用，并通过物体命名等任务的证据，认为左前颞极是负责将意义映射到声音的区域。然而，另一项最近的研究表明，双侧前颞叶损伤是导致临床显著语义障碍所必需的。在本研究中，我们通过评估急性中风患者在结构-功能关系重新组织之前来检验这些假设。我们将 20 名急性中风伴前颞极损伤的患者与 28 名无前颞极损伤的患者进行了比较，这些患者的梗死体积相匹配。我们使用非参数回归方法，根据梗死体积计算了听觉理解和命名任务的平均百分比错误。我们发现，梗死体积是听觉理解和物体命名任务中语义错误产生的唯一预测变量。这一发现支持了以下假设：即使是单侧左前颞极损伤，也不太可能单独导致将意义映射到声音的显著缺陷，尽管它们有助于物体命名和理解的网络。因此，前颞叶可能是物体意义的语义枢纽，但它的作用必须双侧表达，可能是冗余的。
