基于超声影像的上海话鼻化元音发音研究

An articulatory study of Nasalized Vowels in Shanghainese based on Ultrasonic Data

文章使用超声观察上海话前鼻化元音ã、后鼻化元音a^(~)和纯口元音A三者在稳定段中点的静态舌位,以及鼻化元音ã和a^(~)动态的舌位运动,并比较中派发音人和新派发音人鼻化元音与纯口元音的发音差异,以此来说明不同年龄段发音人之间的变化以及普通话对上海话鼻化元音的影响。实验结果显示上海话中派发音人能够区分前鼻化元音ã和后鼻化元音a^(~),前鼻化元音ã的静态舌位比对应的口元音A略靠前,后鼻化元音a^(~)的舌位靠后,在韵母时间段鼻化元音舌位动态变化较少,不具有明显的滑动,基本保持元音的舌位。新派发音人不能区分前鼻化元音ã和后鼻化元音a^(~),在韵母时间段内舌位具有明显的向软腭目标抬升的动作,发音可看作ãŋ/a^(~)ŋ。最后研究对比了鼻化元音和口元音稳定段中点的声学数据,发现鼻化元音的F1比口元音A更低,而超声数据上鼻化元音的舌位并没有显著高于口元音舌位,这可能是由于鼻腔耦合产生的声学效应使得F1降低。

This paper aims to investigate the articulatory differences between[A],[ã],and[a^(~)]by comparison of Ultrasonic static and dynamic tongue positions in Shanghainese.The differences between middle⁃aged and young participants are also observed to illustrate the sound change among participants of different ages and the influence of Mandarin on young participants.Results show that tongue position differences between[ã]and[a^(~)]are detected in middle⁃aged participants.The tongue position of[A]is more posterior than[ã]while more anterior than[a^(~)].Moreover,during the whole rhyme parts,the tongue positions of the nasalized vowel[ã]and[a^(~)]remain stable and without significant dynamic change.However,the patterns of[ã],[a^(~)],and[A]in young participants differ from those in middle⁃aged participants.Young participants cannot differentiate[ã]and[a^(~)]in static tongue positions.And there are significant dynamic changes during whole rhyme parts,which can be viewed as the dynamic patterns of [ãŋ] and [a^(~)ŋ] due to the similar velar articulatory target.Finally,the acoustic data of the middle point in the steady states of nasal and oral vowels are also compared.The F1 data in nasalized vowels are lower than its oral counterparts,which is inconsistent with the result of the Ultrasonic comparison.The inconsistency may be due to the acoustic effect of nasal coupling,which can reduce F1.