手语和口语理解及产生的脑机制对比

The Contrast of Neural Mechanisms for Comprehension and Production between Sign Language and Spoken Language

手语是聋人日常交流的语言,而口语是健听者日常交流的语言。文章从语言理解和产生两个角度,并从词汇,句子和篇章等语言学层面系统地总结和分析了有关手语加工的脑机制的相关文献,并与相应的口语加工脑机制进行对比,揭示了不同层面上的手语和口语加工的神经机制及脑功能侧化特点。分析发现,手语和口语加工具有较大的相似性,主要激活了左半球经典语言区,其中产生过程主要由前部脑区负责,理解过程为后部脑区负责。随着加工复杂程度的增加,有更多脑区特别是右半球的参与加工。二者的差异性主要表现为:1)右脑在手语理解中有更多参与,2)左侧缘上回、顶下小叶在手语产生中有更多参与。手语和口语神经机制对比分析对理解语言的起源、脑的可塑性及聋童的教育等问题均有启发和借鉴意义。

Sign language is the daily used language of deaf people, while spoken language is that for hearing people. Here we reviewed the studies on neural mechanisms for both comprehension and production of sign language and spoken language. Particularly, we compared the neural mechanisms of both languages from different processing level, including word, sentence and context. We found that the two languages activated a similar set of brain regions. Language production mainly activates the anterior part whilst language comprehension activates the posterior part of the brain. The more complex processing is associated with more-involved brain regions, especially the right- hemisphere regions. The differences between two languages are： 1） Right hemisphere is more engaged in sign language comprehension. 2） The left supramarginal gyrus, inferior parietal lobule are more engaged in sign language comprehension. These findings shed deep insights on some important issues including the origins of language, plasticity of brain and education of deaf children.