Cross-language differences in the brain network subserving intelligible speech
Cross-language differences in the brain network subserving intelligible speech
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大脑网络中的跨语言差异有助于可理解的言语
DOI：
10.1073/pnas.1416000112
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发表时间：
2015-03-10
影响因子：
11.1
通讯作者：
Gao, Jia-Hong
中科院分区：
文献类型：
--
作者：
Ge, Jianqiao;Peng, Gang;Gao, Jia-Hong
语言处理通常是左半球主导的。然而，典型的左半球语言区域之间的相互作用是否在不同的语言中有所不同，在很大程度上是未知的。解决这个问题的一个理想方法是跨语言组建模皮层交互，但由于大量的计算需求，这通常受到模型空间和先验假设的约束。利用云计算技术，我们利用功能磁共振动态因果建模分析，比较了颞叶和额叶皮层关键语言区域的4,000多个皮层动力学模型，建立了汉语和英语可理解言语加工共享或特异的无偏信息流图，揭示了汉语言语理解中左右半球的神经动力学。不同语言的母语使用者的大脑是如何处理语言的？是否存在一个适用于所有语言的大脑系统，或者不同的语言由不同的大脑系统支配？第一种观点强调共性，而第二种观点强调特殊性。我们研究了两种非常不同的语言：声调语言（中文）和非声调语言（英语）的处理过程中所涉及的皮质动力学。我们利用功能磁共振成像和动态因果模型分析技术，对大脑颞叶和额叶皮层语言区节点之间的所有可能联系进行了详尽的计算和比较，发现汉语和英语使用者在言语理解过程中，颞叶皮层后部到前部的信息流是共享的，而英语使用者的额下回接受来自左侧颞叶皮质后部的神经信号，汉语使用者的额下回接受来自双侧颞叶皮质前部的神经信号。我们的研究结果表明，虽然语音处理主要是在共同的左半球经典语言区（布罗卡区和韦尼克区）和前颞叶皮层，不同语言群体的语音理解取决于这些大脑区域如何相互作用。此外，右前颞叶皮层，这是至关重要的音调处理，是同样重要的，因为它的左同系物，左前颞叶皮层，在调节皮质动力学的音调语言理解。目前的研究指出了双侧前颞叶皮层在语言理解中的重要性，而这一点在当代流行的言语理解模型中被低估甚至忽视了。
Significance Language processing is generally left hemisphere dominant. However, whether the interactions among the typical left hemispheric language regions differ across different languages is largely unknown. An ideal method to address this question is modeling cortical interactions across language groups, but this is usually constrained by the model space with the prior hypothesis due to massive computation demands. With cloud-computing, we used functional MRI dynamic causal modeling analysis to compare more than 4,000 models of cortical dynamics among critical language regions in the temporal and frontal cortex, established the bias-free information flow maps that were shared or specific for processing intelligible speech in Chinese and English, and revealed the neural dynamics between the left and right hemispheres in Chinese speech comprehension. How is language processed in the brain by native speakers of different languages? Is there one brain system for all languages or are different languages subserved by different brain systems? The first view emphasizes commonality, whereas the second emphasizes specificity. We investigated the cortical dynamics involved in processing two very diverse languages: a tonal language (Chinese) and a nontonal language (English). We used functional MRI and dynamic causal modeling analysis to compute and compare brain network models exhaustively with all possible connections among nodes of language regions in temporal and frontal cortex and found that the information flow from the posterior to anterior portions of the temporal cortex was commonly shared by Chinese and English speakers during speech comprehension, whereas the inferior frontal gyrus received neural signals from the left posterior portion of the temporal cortex in English speakers and from the bilateral anterior portion of the temporal cortex in Chinese speakers. Our results revealed that, although speech processing is largely carried out in the common left hemisphere classical language areas (Broca’s and Wernicke’s areas) and anterior temporal cortex, speech comprehension across different language groups depends on how these brain regions interact with each other. Moreover, the right anterior temporal cortex, which is crucial for tone processing, is equally important as its left homolog, the left anterior temporal cortex, in modulating the cortical dynamics in tone language comprehension. The current study pinpoints the importance of the bilateral anterior temporal cortex in language comprehension that is downplayed or even ignored by popular contemporary models of speech comprehension.