The specialized structure of human language cortex: Pyramidal cell size asymmetries within auditory and language-associated regions of the temporal lobes
The specialized structure of human language cortex: Pyramidal cell size asymmetries within auditory and language-associated regions of the temporal lobes
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DOI：
10.1016/s0093-934x(02)00531-x
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发表时间：
2003-08-01
影响因子：
2.5
通讯作者：
Hutsler, JJ
中科院分区：
文献类型：
--
作者：
Hutsler, JJ
长期以来，大脑皮层内语言的功能偏侧化一直推动着对可能构成语言不对称的结构不对称的研究。大多数结构不对称的检查都集中在语言区及其周围皮质区域的总体大小和形状上。在过去的20年里，几个实验室已经开始记录语言相关皮层区域结构的微观解剖不对称性。这些显微解剖学结果为我们理解大脑皮层语言特化的生物学基础提供了有用的限制和线索。在以前的研究中，我们记录了在皮层浅层的一个特定类别的锥体细胞的大小不对称。目前的工作使用非特异性染色的细胞体，以证明存在的不对称的第三层锥体细胞的大小内的听觉，次级听觉和语言相关的区域的颞叶。具体来说，左半球包含更多最大的锥体细胞，这些细胞被认为是长距离皮质-皮质连接的起源。这些结果进行了讨论的背景下，皮层列和这样的不对称性可能会改变皮层处理。这些发现，再加上几个实验室已经记录的皮层组织中的其他不对称性，清楚地表明左半球听觉和语言皮层的柱状和连接结构与对侧半球的同源区域不同。(C)2003 Elsevier Science（美国）。All rights reserved.
Functional lateralization of language within the cerebral cortex has long driven the search for structural asymmetries that might underlie language asymmetries. Most examinations of structural asymmetry have focused upon the gross size and shape of cortical regions in and around language areas. In the last 20 years several labs have begun to document microanatomical asymmetries in the structure of language-associated cortical regions. Such microanatomic results provide useful constraints and clues to our understanding of the biological bases of language specialization in the cortex. In a previous study we documented asymmetries in the size of a specific class of pyramidal cells in the superficial cortical layers. The present work uses a nonspecific stain for cell bodies to demonstrate the presence of an asymmetry in layer III pyramidal cell sizes within auditory, secondary auditory and language-associated regions of the temporal lobes. Specifically, the left hemisphere contains a greater number of the largest pyramidal cells, those that are thought to be the origin of long-range cortico-cortical connections. These results are discussed in the context of cortical columns and how such an asymmetry might alter cortical processing. These findings, in conjunction with other asymmetries in cortical organization that have been documented within several labs, clearly demonstrate that the columnar and connective structure of auditory and language cortex in the left hemisphere is distinct from homotopic regions in the contralateral hemisphere. (C) 2003 Elsevier Science (USA). All rights reserved.