cortical dynamics of acoustic and phonological processing in speech perception皮层动态言语知觉的声学和语音处理.pdf

Cortical Dynamics of Acoustic and Phonological Processing in Speech Perception 1,2. 1,3. 4 1 5 6 Linjun Zhang , Jie Xi , Guoqing Xu , Hua Shu *, Xiaoyi Wang , Ping Li * 1 State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China, 2 College of Chinese Studies, Beijing Language and Culture University, Beijing, China, 3 Institute of Psychology, Chinese Academy of Sciences, Beijing, China, 4 Department of Psychology, Dalian Medical University, Dalian, China, 5 Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, China, 6 Department of Psychology and Center for Language Science, Pennsylvania State University, University Park, Pennsylvania, United States of America Abstract In speech perception, a functional hierarchy has been proposed by recent functional neuroimaging studies: Core auditory areas on the dorsal plane of superior temporal gyrus (STG) are sensitive to basic acoustic characteristics, whereas downstream regions, specifically the left superior temporal sulcus (STS) and middle temporal gyrus (MTG) ventral to Heschl’s gyrus (HG) are responsive to abstract phonological features. What is unclear so far is the relationship between the dorsal and ventral processes, especially with regard to whether low-level acoustic processing is modulated by high-level phonological processing. To address the issue, we assessed sensitivity of core auditory and downstream regions to acoustic and phonological variations by using within- and across-category lexical tonal continua with equal physical intervals. We found that relative to within-category variation, across-category variation elicited stronger activation in the left middle MTG (mMTG