Zhou Xinhui, Espy-Wilson Carol Y, Boyce Suzanne, Tiede Mark, Holland Christy, Choe Ann
Speech Communication Laboratory, Institute of Systems Research, and Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742, USA.
J Acoust Soc Am. 2008 Jun;123(6):4466-81. doi: 10.1121/1.2902168.
Speakers of rhotic dialects of North American English show a range of different tongue configurations for /r/. These variants produce acoustic profiles that are indistinguishable for the first three formants [Delattre, P., and Freeman, D. C., (1968). "A dialect study of American English r's by x-ray motion picture," Linguistics 44, 28-69; Westbury, J. R. et al. (1998), "Differences among speakers in lingual articulation for American English /r/," Speech Commun. 26, 203-206]. It is puzzling why this should be so, given the very different vocal tract configurations involved. In this paper, two subjects whose productions of "retroflex" /r/ and "bunched" /r/ show similar patterns of F1-F3 but very different spacing between F4 and F5 are contrasted. Using finite element analysis and area functions based on magnetic resonance images of the vocal tract for sustained productions, the results of computer vocal tract models are compared to actual speech recordings. In particular, formant-cavity affiliations are explored using formant sensitivity functions and vocal tract simple-tube models. The difference in F4/F5 patterns between the subjects is confirmed for several additional subjects with retroflex and bunched vocal tract configurations. The results suggest that the F4/F5 differences between the variants can be largely explained by differences in whether the long cavity behind the palatal constriction acts as a half- or a quarter-wavelength resonator.
北美英语卷舌方言的使用者在发/r/音时会呈现出一系列不同的舌位形态。这些变体产生的声学特征在前三个共振峰上无法区分[德拉特雷，P.，和弗里曼，D. C.，（1968年）。“通过X射线电影对美式英语/r/的方言研究”，《语言学》44卷，第28 - 69页；韦斯特伯里，J. R.等人（1998年），“美式英语/r/发音中说话者之间的舌部发音差异”，《言语通信》26卷，第203 - 206页]。考虑到所涉及的声道形态差异极大，为何会如此令人费解。在本文中，对两名发“卷舌”/r/和“束状”/r/时F1 - F3呈现相似模式但F4和F5之间间距差异很大的受试者进行了对比。利用有限元分析以及基于声道磁共振图像的面积函数来进行持续发音，将计算机声道模型的结果与实际语音录音进行比较。特别地，使用共振峰敏感度函数和声道简单管模型来探究共振峰 - 腔体关系。对于另外几名具有卷舌和束状声道形态的受试者，也证实了他们在F4/F5模式上的差异。结果表明变体之间F4/F5的差异在很大程度上可以通过腭部收缩后方的长腔体是充当半波长还是四分之一波长谐振器的差异来解释。
