社会语义整合的脑机制

Semantic integration refers to the process of combining small semantic units into larger ones. It has been found that the semantic memory system has fine subdivisions supporting different types of semantic information. Because the semantic integration system relies on information from semantic memory, it may also have subdivisions to process different types of semantic information. According to the literature, the semantic integration system may contain several regions that are sensitive to social semantic information. Social semantic information refers to the semantic information that is related to the interactions between people. The dissociation between social and nonsocial semantic representations has been well demonstrated in studies of semantic memory. In our recent study, we found that the right temporoparietal junction and middle temporal gyrus selectively contribute to social semantic integration during discourse comprehension. In this project, we will explore the brain areas supporting different levels (semantic feature binding, conceptual combination, event integration, meta-representation construction, and situation model building) of social semantic integration and investigate how these areas interact with each other using fMRI. Our findings will indicate how social semantics are integrated in human brain and will provide new insights into the neural correlates of semantic processing, language comprehension, and social cognition.

语义整合是指将小的语义单元衔接成更大的语义单元的加工。语义整合必须调用语义记忆中的信息，因此在认知和脑机制上与语义记忆有紧密联系。研究发现，语义记忆的脑机制存在基于信息类型的分化，由此推论语义整合的脑机制亦可能存在基于信息类型的分化。基于已有文献，语义整合系统中可能存在多处对社会语义敏感的脑区。社会语义是指与人际互动相关的语义信息。语义记忆研究已经发现社会语义表征与其他语义表征在脑机制上有所分离。我们的新近研究发现右侧颞顶接合部和颞中回选择性地支持社会语义整合，为社会语义整合与一般语义整合的脑机制分离提供了初步证据。在本项目中，我们将通过一系列功能磁共振实验考察多个层次（语义特征绑定、概念组合、事件承接、元表征构建、情境模型构建）的社会语义整合所依赖的脑区，并研究这些脑区间的功能交互模式。本项目将系统揭示社会语义整合的脑机制，为语义加工、语言理解、社会认知等领域的研究提供新启示。

社会语义是一类特殊的语义信息，社会语义的理解承接了语言理解和社会认知两大领域，并且具有相对特异性的神经关联。本项目考察了社会语义在短语、句子、篇章等多个层级的整合机制以及相关脑区的功能联系。研究有三方面主要发现。第一，揭示了一个较为完整的、特异性的社会语义整合系统，并且在短语、句子、篇章层级上分别倚重不同脑区。第二，揭示社会语义工作记忆的神经关联，并且发现社会语义工作记忆是诱发左侧颞叶前部外侧和颞顶接合部腹侧经典句子加工效应的真正原因，挑战了经典的句子加工脑机制观点。最后，揭示了社会语义加工脑网络的多重功能性，即社会语义功能与非语义功能共存。研究深入揭示了社会语义整合及其相关认知活动的神经基础，为继续深入研究相关问题提供了基础和借鉴，并挑战了人们对于部分脑区功能的经典认知。