RESUMEN
The purpose of this study is to test a methodology for describing the articulation of vowels. High front vowels are a test case because some theories suggest that high front vowels have little cross-linguistic variation. Acoustic studies appear to show counterexamples to these predictions, but purely acoustic studies are difficult to interpret because of the many-to-one relation between articulation and acoustics. In this study, vocal tract dimensions, including constriction degree and position, are measured from cinéradiographic and x-ray data on high front vowels from three different languages (North American English, French, and Mandarin Chinese). Statistical comparisons find several significant articulatory differences between North American English /i/ and Mandarin Chinese and French /i/. In particular, differences in constriction degree were found, but not constriction position. Articulatory synthesis is used to model the acoustic consequences of some of the significant articulatory differences, finding that the articulatory differences may have the acoustic consequences of making the latter languages' /i/ perceptually sharper by shifting the frequencies of F(2) and F(3) upwards. In addition, the vowel /y/ has specific articulations that differ from those for /i/, including a wider tongue constriction, and substantially different acoustic sensitivity functions for F(2) and F(3).
Asunto(s)
Lenguaje , Fonética , Acústica del Lenguaje , Estimulación Acústica/métodos , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Paladar Duro/anatomía & histología , Paladar Duro/fisiología , Faringe/anatomía & histología , Faringe/fisiología , Pliegues Vocales/anatomía & histología , Pliegues Vocales/fisiologíaRESUMEN
Traditional models of mappings from midsagittal cross-distances to cross-sectional areas use only local cross-distance information. These are not the optimal models on which to base the construction of a mapping between the two domains. This can be understood because phonemic identity can affect the relation between local cross-distance and cross-sectional area. However, phonemic identity is not an appropriate independent variable for the control of an articulatory synthesizer. Two alternative approaches for constructing cross-distance to area mappings that can be used for articulatory synthesis are presented. One is a vowel height-sensitive model and the other is a non-parametric model called loess. These depend on global cross-distance information and generally perform better than the traditional models.
Asunto(s)
Faringe/anatomía & histología , Fonética , Habla/fisiología , Pliegues Vocales/anatomía & histología , Análisis de Varianza , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Hueso Paladar/anatomía & histología , Caracteres Sexuales , Lengua/anatomía & histologíaRESUMEN
The purpose of this study was to devise a consistent and robust method for defining vocal tract constrictions in high front vowels. A procedure was devised to find the length and position of the articulatory constriction in high front vowels that is not sensitive to local fluctuations in vocal tract shape and to the constriction-defining parameters. A method based on a visual examination of plots for constriction length and position as functions of the constriction-defining parameters was found to provide stable constriction definitions.
Asunto(s)
Boca/fisiología , Fonética , Habla/fisiología , Pliegues Vocales/fisiología , Fenómenos Biomecánicos , Humanos , Lenguaje , Modelos Biológicos , Boca/diagnóstico por imagen , Radiografía , Pliegues Vocales/diagnóstico por imagenRESUMEN
In a re-analysis of x rays of speakers producing Swedish vowels, midsagittal pharyngeal dimensions were predicted from anterior tongue positions using procedures based on estimated tongue pellet positions. Principal component analysis was used to reduce the number of pellet degrees of freedom from eight to three prior to applying linear regression from these three independent variables to dependent vocal tract midsagittal cross distances. Except for the regions around the laryngopharynx and uvula, the pharynx dimensions were predictable from linear regressions and were significant at the p<0.05 level. Numerical experiments show that it is crucial to reduce the number of independent variables in tests of statistical significance.