汉语自闭症儿童如何处理语音关键信息：音调加工的神经机制研究

Difficulty in verbal communication in complex situations is one of the hallmarks of children with autism. Existing research from the West lacking evidence from linguistically diverse samples, have not sufficiently investigated information processing in autism under a linguistically informed framework. The underlying neural mechanisms of speech perception in autism remain unclear. Guided by the native language neural specialization account, the proposed research will focus on the cortical processing of pitch in Chinese-speaking children with autism to examine whether these children can effectively represent the key phonetic information in their native language. The study will manipulate the linguistic relevance of tonal stimuli presented in both syllabic- and suprasyllabic-level sounds, and will implement various complex acoustic conditions. EEG technique with excellent temporal resolution will be utilized to record cortical responses to the different phonetic units under different listening conditions and information processing stages. The results will provide in-depth knowledge for the language-general and language-specific aspects of information processing in autism as well as verify the clinical significance of native language neural specialization and the corresponding psychological processes. The conclusions will provide linguistically diverse evidence for theory construction and offer empirical guidance for the development of cognitively and linguistically appropriate intervention instruments for children with autism.

复杂情境中的言语交流困难是自闭症儿童的显著特征之一。以往西方研究缺少语言多样性证据，尚缺乏从契合语言加工规律的角度对自闭症语音信息加工方式的系统考察，与之相关脑神经机制仍不甚清楚。本课题以母语神经专门化理论为指导，重点考察汉语自闭症儿童的音调皮层加工，以此推断这些儿童能否有效表征语音中的关键信息。研究将精细调控音调的语言学变量、设置音节和超音节刺激并纳入不同类型复杂声学条件，通过高时间精度的EEG技术记录自闭症儿童对不同加工单元、在不同加工条件和信息加工阶段下的皮层反应，全面系统地揭示自闭症语言一般性和语言特异性的感知觉规律，以此建立一套关于自闭症母语神经专门化异常的神经行为学指标，并验证母语神经专门化和与之对应的心理加工过程的临床病理学意义。结果将服务于自闭症认知言语发展理论模型建构、为自闭症基础研究提供跨语言的多元证据，并为开发切合自闭症儿童感知觉特性、语言适宜的干预工具提供实证指导。

本项目借助高时间分辨率的EEG技术和较高空间分辨率的fNIRS技术，以汉语孤独症儿童为研究对象，通过精细调控听觉刺激的语言学和声学属性，从音段、超音段、韵律和连续语音多个不同角度揭示了孤独症儿童对关键语音线索的非典型加工方式。研究内容包括了汉语孤独症儿童音节和超音节音调加工的神经专门化研究、汉语孤独症儿童的听觉语言加工大脑偏侧化研究、扩大化语音对孤独症儿童语音神经编码的影响机制研究、以及孤独症儿童语言韵律时间协调研究。研究结论支持了孤独症母语神经专门化不足假说，并且，从神经行为学的层面上证实了言语障碍孤独症儿童在加工复杂听觉语言刺激时的独特困难。本项目的成果以4篇论文和若干会议摘要形式发表在重要学术刊物以及被国际学术会议收录，完成了项目设立的目标。针对项目研究内容揭示的孤独症儿童听觉信息加工和语音感知异常表现，我们初步确立了以优化母语神经专门化加工方式为核心的后续临床转化目标，目前已经开始与数字医疗团队共同开展针对孤独症儿童、语言和认知适宜的康复训练方案研发工作。