Wang Han, Gao Fei, Zhang Jingwei
Faculty of Arts and Humanities, University of Macau, Macau SAR 999078, China.
Centre for Cognitive and Brain Sciences, University of Macau, Macau SAR 999078, China.
Brain Sci. 2024 Dec 17;14(12):1271. doi: 10.3390/brainsci14121271.
BACKGROUND/OBJECTIVES: Previous studies have examined the role of working memory in cognitive tasks such as syntactic, semantic, and phonological processing, thereby contributing to our understanding of linguistic information management and retrieval. However, the real-time processing of phonological information-particularly in relation to suprasegmental features like tone, where its contour represents a time-varying signal-remains a relatively underexplored area within the framework of Information Processing Theory (IPT). This study aimed to address this gap by investigating the real-time processing of similar tonal information by native Cantonese speakers, thereby providing a deeper understanding of how IPT applies to auditory processing.
Specifically, this study combined assessments of cognitive functions, an AX discrimination task, and electroencephalography (EEG) to investigate the discrimination results and real-time processing characteristics of native Macau Cantonese speakers perceiving three pairs of similar tones.
The behavioral results confirmed the completed merging of T2-T5 in Macau Cantonese, and the ongoing merging of T3-T6 and T4-T6, with perceptual merging rates of 45.46% and 27.28%, respectively. Mismatch negativity (MMN) results from the passive oddball experiment revealed distinct temporal processing patterns for the three tone pairs. Cognitive functions, particularly attention and working memory, significantly influenced tone discrimination, with more pronounced effects observed in the mean amplitude of MMN during T4-T6 discrimination. Differences in MMN peak latency between T3-T6 and T4-T6 further suggested the use of different perceptual strategies for these contour-related tones. Specifically, the T3-T6 pair can be perceived through early signal input, whereas the perception of T4-T6 relies on constant signal input.
This distinction in cognitive resource allocation may explain the different merging rates of the two tone pairs. This study, by focusing on the perceptual difficulty of tone pairs and employing EEG techniques, revealed the temporal processing of similar tones by native speakers, providing new insights into tone phoneme processing and speech variation.
背景/目的：以往的研究探讨了工作记忆在句法、语义和语音处理等认知任务中的作用，从而有助于我们理解语言信息的管理和检索。然而，语音信息的实时处理——特别是与声调等超音段特征相关的处理，其轮廓代表一个随时间变化的信号——在信息处理理论（IPT）框架内仍是一个相对未被充分探索的领域。本研究旨在通过调查以粤语为母语者对相似声调信息的实时处理来填补这一空白，从而更深入地了解IPT如何应用于听觉处理。
具体而言，本研究结合认知功能评估、AX辨别任务和脑电图（EEG）来调查以澳门粤语为母语者对三对相似声调的辨别结果和实时处理特征。
行为结果证实了澳门粤语中T2-T5的完全合并，以及T3-T6和T4-T6的正在进行的合并，感知合并率分别为45.46%和27.28%。被动奇偶数实验的失配负波（MMN）结果揭示了三对声调的不同时间处理模式。认知功能，特别是注意力和工作记忆，对声调辨别有显著影响，在T4-T6辨别期间MMN的平均振幅中观察到更明显的影响。T3-T6和T4-T6之间MMN峰值潜伏期的差异进一步表明，对于这些与轮廓相关的声调使用了不同的感知策略。具体而言，T3-T6对可以通过早期信号输入来感知，而T4-T6的感知依赖于持续的信号输入。
这种认知资源分配的差异可能解释了两对声调的不同合并率。本研究通过关注声调对的感知难度并采用EEG技术，揭示了母语者对相似声调的时间处理，为声调音素处理和语音变异提供了新的见解。
