Nasal coarticulation and sound-change: a real-time MRI study

鼻协同运动和声音变化：实时 MRI 研究

• 批准号: 327766007
• 负责人: Professor Dr. Jonathan Harrington
• 金额: --
• 依托单位: Max-Planck-Institut für biophysikalische Chemie (Karl-Friedrich-Bonhoeffer-Institut) (aufgelöst)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/327766007?language=en
• 关键词: Nasal; coarticulation; sound; change; real

Speech production is highly context-dependent because the sounds of speech overlap and influence each other in time. This is also true for sound sequences in which a vowel is followed by a nasal consonant in fluent speech: the velum lowering gesture that is associated with the nasal stop is initiated during the vowel, i.e. before the oral constriction for the nasal stop is achieved. Thus, in many languages, vowels are typically more nasalised before nasal than before oral consonants. In some languages like French, this type of phonetic variation has evolved historically into a nasal-oral contrast in the vowel combined with a deletion of the following nasal consonant. Fundamental to explaining the phonologisation of nasalisation is an understanding of how a nasal consonant's two primary articulators – the velum and the nasal consonant's oral constriction – become disassociated from each other, as in e.g. French main (‘hand’) /mɛ̃/ from Latin manus, in which the alveolar contact for the /n/ presumably initially lenited and was then lost as nasalisation in the vowel increased. The overall purpose of this project is to determine the phonetic conditions that could cause nasalisation to become increasingly associated with an oral vowel in a nasal context. Building on the fruitful results of the preceding proposal, this project will focus more specifically on the inter-gestural reorganisation of the tongue and the velum when phonetic conditions are modified, especially if the segment and word duration is decreased during speech due to different speech modes (read speech vs. spontaneous speech) or due to controlled speech rates (moderate vs. fast speech). The analysis will primarily focus on highly frequent function words containing post-vocalic nasals in which reduction is more likely than in less frequent content words. Real-time MRI will be used for recording up to 60 speakers of Standard German to track the movement of the velum in relation to other articulators, in particular the tongue tip. German is appropriate for such a study both because there are no known sound changes in progress involving nasals and because nasals occur in such a wide range of different contexts. For data acquisition, a high temporal resolution of 80 fps (12.5 ms) will be used, which is particularly advantageous for capturing details of small, fast tongue-tip movements whose analysis forms a key part of the renewal proposal. For the purposes of analysing sound change from time-varying speech data, the renewal proposal will make use of functional principal component analysis (FPCA), a method that expresses time-varying shapes of signals as a set of principal components which are time-varying functions. This project will lead to a deeper understanding of how the inter-gestural reorganisation of the velum and the tongue tip is affected by different speaking styles, sound contexts and word frequency, and how such variation provides the conditions for sound change.

语音产生是高度依赖于上下文的，因为语音的声音在时间上相互重叠和影响。这也适用于在流利的语音中元音后面跟着鼻音辅音的声音序列：与鼻音塞相关的软腭降低手势在元音期间开始，即在鼻音塞的口腔收缩实现之前。因此，在许多语言中，元音通常在鼻音之前比在口语辅音之前更鼻音化。在一些语言中，如法语，这种语音变异在历史上演变成元音的鼻口对比，并删除了后面的鼻辅音。解释鼻音化的音位化的基础是理解鼻音辅音的两个主要发音器官-软腭和鼻音辅音的口腔收缩-是如何彼此分离的，例如法语main（'hand'）/m/来自拉丁语manus，其中/n/的肺泡接触可能最初是宽松的，然后随着元音中鼻音化的增加而消失。这个项目的总体目的是确定语音条件，可能会导致鼻音越来越多地与鼻环境中的口头元音相关联。 基于上述建议的丰硕成果，该项目将更具体地关注语音条件发生变化时舌头和软腭的手势间重组，特别是如果由于不同的语音模式（阅读语音与自发语音）或由于受控的语音速率（中等与快速语音），语音期间的片段和单词持续时间减少。分析将主要集中在高频率的功能词包含后元音鼻音，其中减少是更有可能比在不太频繁的内容词。 实时MRI将用于记录多达60名标准德语的说话者，以跟踪软腭相对于其他发音器官（特别是舌尖）的运动。德国是适合这样的研究，因为没有已知的声音变化的进展涉及鼻音，因为鼻音发生在这样一个广泛的不同的背景。对于数据采集，将使用80 fps（12.5 ms）的高时间分辨率，这对于捕获小而快的舌尖运动的细节特别有利，其分析形成了更新建议的关键部分。为了分析来自时变语音数据的声音变化，更新建议将利用函数主成分分析，这是一种将信号的时变形状表示为一组时变函数的主成分的方法。 该项目将导致更深入地了解软腭和舌尖的手势间重组如何受到不同说话风格，声音上下文和词频的影响，以及这种变化如何为声音变化提供条件。