Department of Linguistics, University of Illinois at Urbana-Champaign, 4080 Foreign Languages Building, 707 South Mathews Avenue, Urbana, Illinois 61801, USA.
J Acoust Soc Am. 2012 Jan;131(1):455-65. doi: 10.1121/1.3665998.
There is increasing evidence that fine articulatory adjustments are made by speakers to reinforce and sometimes counteract the acoustic consequences of nasality. However, it is difficult to attribute the acoustic changes in nasal vowel spectra to either oral cavity configuration or to velopharyngeal opening (VPO). This paper takes the position that it is possible to disambiguate the effects of VPO and oropharyngeal configuration on the acoustic output of the vocal tract by studying the position and movement of the tongue and lips during the production of oral and nasal vowels. This paper uses simultaneously collected articulatory, acoustic, and nasal airflow data during the production of all oral and phonemically nasal vowels in Hindi (four speakers) to understand the consequences of the movements of oral articulators on the spectra of nasal vowels. For Hindi nasal vowels, the tongue body is generally lowered for back vowels, fronted for low vowels, and raised for front vowels (with respect to their oral congeners). These movements are generally supported by accompanying changes in the vowel spectra. In Hindi, the lowering of back nasal vowels may have originally served to enhance the acoustic salience of nasality, but has since engendered a nasal vowel chain shift.
越来越多的证据表明，说话者会进行精细的发音调整，以加强甚至有时抵消鼻音的声学效果。然而，很难将鼻腔元音频谱中的声学变化归因于口腔结构或咽腔开口（VPO）。本文认为，通过研究口腔元音和鼻腔元音发音过程中舌位和唇位的变化，可以区分咽腔开口和口腔结构对声道输出的影响。本文使用同时采集的发音、声学和鼻腔气流数据，研究了在发所有印地语口腔元音和音位上的鼻腔元音时，口腔发音器官的运动对鼻腔元音频谱的影响。对于印地语的鼻腔元音，舌体在发后元音时通常会下降，在发低元音时会向前移动，在发前元音时会向上移动（相对于它们的口腔对应元音）。这些运动通常伴随着元音频谱的变化。在印地语中，后鼻音的降低最初可能是为了增强鼻音的声学显著性，但后来导致了鼻腔元音链的转移。
