A distributed dynamic brain network mediates linguistic tone representation and categorization

NeuroImage

Zhenzhong Gan¹  Fernando Llanos²  Bharath Chandrasekaran³  Danting Meng³  Patrick C.M. Wong³  Suiping Wang⁴  Gangyi Feng⁵ 

[1] Brain and Mind Institute, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China;Corresponding authors.;Center for the Study of Applied Psychology and School of Psychology, South China Normal University, Guangzhou 510631, China;Department of Communication Science and Disorders, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States;Department of Linguistics and Modern Languages, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China;

关键词: Categorization decision;    Lexical tones;    Neural decoding;    Neural representation;    Perceptual constancy;    Speech categorization;   

DOI  :  

来源: DOAJ

【 摘 要 】

Successful categorization requires listeners to represent the incoming sensory information, resolve the “blooming, buzzing confusion” inherent to noisy sensory signals, and leverage the accumulated evidence towards making a decision. Despite decades of intense debate, the neural systems underlying speech categorization remain unresolved. Here we assessed the neural representation and categorization of lexical tones by native Mandarin speakers (N = 31) across a range of acoustic and contextual variabilities (talkers, perceptual saliences, and stimulus-contexts) using functional magnetic imaging (fMRI) and an evidence accumulation model of decision-making. Univariate activation and multivariate pattern analyses reveal that the acoustic-variability-tolerant representations of tone category are observed within the middle portion of the left superior temporal gyrus (STG). Activation patterns in the frontal and parietal regions also contained category-relevant information that was differentially sensitive to various forms of variability. The robustness of neural representations of tone category in a distributed fronto-temporoparietal network is associated with trial-by-trial decision-making parameters. These findings support a hybrid model involving a representational core within the STG that operates dynamically within an extensive frontoparietal network to support the representation and categorization of linguistic pitch patterns.

【 授权许可】

Unknown