Temporal dynamics of perisylvian activation during language processing in children and adults
Temporal dynamics of perisylvian activation during language processing in children and adults
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DOI：
10.1016/j.neuroimage.2008.03.027
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发表时间：
2008-07-15
期刊：
影响因子：
5.7
通讯作者：
Friederici, Angela D.
中科院分区：
文献类型：
--
作者：
Brauer, Jens;Neumann, Jane;Friederici, Angela D.
众所周知，人类大脑皮层的皮层周边区在语言处理中起着重要作用。尤其是上颞叶皮质(STC)和下额叶皮质(IFC)在语言理解中的特殊作用已被研究。在目前的研究中，利用6岁儿童和成人的功能成像数据，特别关注血氧水平依赖(BOLD)反应时间过程，研究了两个半球这些与语言相关的大脑区域的招募时间与年龄的关系。结果表明，儿童的激活时间进程与成人不同。首先，孩子们总体上表现出大胆回应的高峰期。其次，儿童的IFC反应比他们的STC反应晚得多，而在成年人中，这两个地区的差异没有那么明显。在STC内，两组人都显示出相似的区域U型激活模式，在STC围绕Heschl回的中段体素峰值最快，前后方向的潜伏期较长，这表明成人和儿童在颞区的信息流大致相似。最后，与成人相比，儿童在时间上表现出右半球优先于左半球的激活。观察到的儿童和成人之间的总体潜伏期差异符合大脑周围区域持续成熟的假设以及它们之间的联系。大胆计时的功能观点认为，与成人相比，儿童的处理成本更高，这是由于语言处理过程更慢、自动化程度更低，特别是那些位于国际金融中心的语言处理过程，这是一种发展变化。观察到的大脑半球差异在儿童语言理解过程中高度依赖基于右半球的超段信息处理的发展模型下进行了讨论。(C)2008 Elsevier Inc.保留所有权利。
The perisylvian region of the human cortex is known to play a major role in language processing. Especially the superior temporal cortex (STC) and the inferior frontal cortex (IFC) have been investigated with respect to their particular involvement in language comprehension. In the present research, the timing of recruitment of these language-related brain areas in both hemispheres was examined as a function of age using functional imaging data of 6-year-old children and adults with a special focus on blood oxygenation level dependent (BOLD) response time courses. The results show that children's activation time courses differ from that of adults. First, children show an overall later peak of BOLD responses. Second, children's IFC responds much later than their STC, while in adults the difference between both regions is less pronounced. Within the STC, both groups show similar regionally U-shaped activation patterns with fastest peaks in voxels at the STC's mid-portion around Heschl's gyrus and longer latencies in anterior and posterior directions, suggesting a coarsely similar information flow in adults and children in the temporal region. Finally, children in contrast to adults, display a temporal primacy of right over left hemispheric activation. The observed overall latency differences between children and adults are in line with the assumption of ongoing maturation in perisylvian brain regions and the connections between them. A functional perspective on BOLD timing argues for a developmental change from higher processing costs in children compared to adults due to slower and less automatic language processes, in particular those located in the IFC. The observed hemispheric differences are discussed in the context of developmental models assuming a high reliance on right-hemisphere-based suprasegmental information processing during language comprehension in childhood. (c) 2008 Elsevier Inc. All rights reserved.