强调与对比影响语篇理解的认知过程及其神经机制

The ability to communicate through language is a unique and important human attribute. Previous studies have revealed the cognitive mechanisms of language comprehension. However, an interesting issue is that people find it easy to understand pragmatic information contained in sentences/discourses, though this information is generally implicit. We know little about the cognitive and neuronal mechanisms underlying this process. An important type of pragmatic information is emphasis. Our recent studies show that emphasis affects attention allocation in discourse comprehension; moreover, emphasis also implies a contrast between the emphasized target and other potential targets. However, additional important questions need now to be answered. How is the contrast between the emphasized and other targets established? How does this affect on-line discourse comprehension? What kinds of targets can be suitable contrastive targets? And how does this kind of pragmatic information processing affect discourse comprehension? The present project will explore the cognitive processes and neural mechanisms underlying the influences of emphasis and contrast processing on discourse comprehension. First, we will explore how linguistic emphasis and visual emphasis direct readers to build up the contrastive relationship between discourse elements, and thereby reveal the influence of emphasis and contrast on discourse comprehension. Second, we will explore how concept contrast and social comparison restrict potential contrastive relationships between elements and thus affect discourse comprehension. Lastly, we will integrate these results to provide an account of the interaction between the contrastive relationship (structural-level) and the contrastive targets (content-level) and their combined influence on discourse comprehension, to construct and develop a theory and model of discourse comprehension.

在人类演化的历程中，语言发挥了至关重要的作用。前人研究系统考察了语言理解的基本认知过程。然而，语言理解中，读者/听者往往能够提取并加工话里行间隐含的“言外之意”（语用信息），而该过程所涉及的认知及神经机制，迄今了解甚少。强调就是这样的一种语用信息。我们的前期研究发现，强调不但引导读者的注意分配，还引导读者将强调对象与相关对象进行对比。那么，强调引导对比关系建构的认知过程和神经机制是怎样的？在对比的过程中涉及到哪些对象的加工？这些语用信息的加工对语篇理解产生什么样的影响？本项目关注强调与对比对语篇理解的影响及其认知神经机制。首先我们考察语言强调和视觉强调引导读者建构对比关系的过程，其次我们考察概念对比和社会比较如何限制对比关系的建构；最后我们综合上述研究结果，揭示对比关系建构（结构层面）和对比对象选择（内容层面）的相互作用及其对语篇理解的影响，为发展和完善语篇理解理论模型提供实证支持。

语篇里蕴含着丰富的信息。人们在理解语篇的时候，除了加工基本的句法和语义信息，还需要整合语篇中各种来源的信息，以达成对语篇的完整理解。强调是一种表达方式，常常用来突显语篇中的重要信息。采用语言学手段进行的强调（如标记词“是”），往往被认为隐含着对比等语用信息。本项目意图考察强调隐含对比信息的认知过程及其神经机制，并探究适合建构对比关系的对比对象特征。通过一系列眼动和ERP实验，我们系统考察了语言学强调隐含的对比信息的认知过程和神经机制，及视觉强调是否具有相似的功能；并从概念范畴和社会身份范畴的角度，分别考察了涉及概念对比和社会比较时，对比对象特征对语篇理解的影响，结果发现：（1）语言学强调调控读者注意分配，读者加工强调词时与注意相关的P2效应增强；语言学强调还隐含对比信息并引导读者建构语篇中的对比关系，对比关系建构失败时与句末整合相关的P300效应增强；（2）视觉强调调控读者注意分配，促进强调词的加工，但可能不引导读者建构对比关系；（3）语言学强调引导对比关系建构，当该过程与语篇逻辑冲突时语篇即时整合变得困难；（4）在语篇语义整合过程中，相同范畴的概念容易进行对比，不同范畴的则较难；此外，理解者根据概念范畴预期对比对象；（5）当语篇内容涉及社会比较时，对比对象社会身份的差异影响对比关系的建构；而不涉及社会比较时，对比关系建构受社会身份差异的影响较小。综上，本项目揭示了语篇理解中语言学强调引导对比关系建构的过程及机制，探讨了对比关系建构中对比对象的特征，进一步发展和完善了语篇理解理论模型，推动语篇理解研究的发展。