语音处理的神经电生理学基础研究进展

The Progress of Research on Basis of Neuroelectrophysiology in Speech Processing

解码大脑在语音处理过程中涉及的信息加工层级结构、皮质响应机制及功能连接模式,是神经语言学领域的研究重点.以语音信息加工时序为依据,可将该认知过程划分为:初级声学信号时频编码(spectrotemporal analysis of primary acoustic signals)、音素处理(phonemic processing)以及词汇-语义加工(lexical-semantic processing)3个处理阶段.目前,研究者已对各阶段的神经机制进行了广泛且深入的研究,但不同模型理论/假说难以整合互补,有必要进行梳理与总结.本文将以大脑处理语音信息的3个阶段为主线,以电生理学方法为侧重范式,对各阶段下的皮质映射、神经振荡模式以及事件相关响应机制等神经基础研究现状进行总结评述,以期为进一步了解语音信号如何在人脑中进行处理和表达等相关研究提供一定的参考.

The investigation into neural basis ofspeech processing,including distributed hierarchical organization,neural mechanisms,and functional connectivity of brain,stands in the central of neurolinguistic research.In line with the sequence of speech processing,it can be subdivided into three processing stages:spectrotemporal analysis of primary acoustic signals,phonemic processing,and lexical-semantic processing.Despite underlying neural mechanisms of these stages have been investigated extensively and intensively,it appears that there are still inconsistencies and controversies between different model theories/hypotheses.Consequently,it is crucial to sort out and summarize them.The present review takes the three speech processing stages of the brain as the main line and reviews the research status of neurological mechanism under each stage,covers cortical mapping,neural oscillations,and event-related potential characteristics.Of note,this review focuses more on observations based on the electrophysiological approaches.We aiming to synthesize the latest findings of this field and provide new insights for understanding how speech signals are represented and processed in the human brain.