Sublingual Cavity Research Articles

Sound production in fricative consonants

A series of experiments with mechanical models of fricative consonant articulatory configurations has been conducted to determine where in the tract the turbulence noise is generated and the spectral characteristics of that noise. The latest models, based on a combination of x-ray, EPG, and photographic data, have the correct midsagittal profile and area function, and thus have the most realistic shape of model work to date. Data obtained from /s, ∫/ substantiate earlier results based on a different subject [C. H. Shadle, J. Acoust. Soc. Am. Suppl. 1 84, S115 (1988): also in Speech Production and Speech Modelling, edited by W. Hardcastle and A. Marchal, Proc. of NATO-ASI, Kluwer Acad., pp. 127–219 (1990)] and results from extremely idealized models [C. H. Shadle, Proc. 12th ICA, paper A3–4, Toronto (1986)]. Comparisons across a range of flow rates, with and without sublingual cavity, between measured source and farfield spectra, and between speech and model data for /s, ∫, ç, x/, lead to source parameters, a distinction between two source types, and to the conclusion that the three-dimensional shape of the tract is crucial in determining source parameters: These parameters can be used in a model based on one-dimensional sound propagation. Three-way comparisons between far-field sound measured (1) for the models, (2) for actual utterances, and (3) for far-field sound predicted from measured source parameters used in a model based on one-dimensional sound propagation will be shown. [Work supported by SERC.]

Acoustic estimations of the front cavity in apical stops

Sweep-tone measurements of front-cavity resonances in apical stops are reported. Volumes inferred from resonance frequency data are presented as a function of place of articulation. The results indicate that, for post-dental points of contact, a cavity located under the tongue tip is formed. It is shown that this sublingual cavity plays a very important role in shaping the spectral structure of apical stops.

Distinctive characters of the articulation of r-like sounds

Linguists have been paying attention to r-like sounds for a long time, trying to find both acoustic and articulatory aspects of the distinctive features of these sounds. Ladefoged et al. [J. Phon. 11, 291–302 (1983)] explained the grouping of these sounds across languages by “family resemblance” in articulation. Lindau [Phonet. Linguist., 157–168 (1985)] gave the same explanation to the grouping from an acoustic point of view. This study focuses on analyzing the place of articulation of r-like sounds by studying x-ray data from English, Chinese, Tamil, Telugu, Hindi, Urdu, Polish, and Russian. It argues for the extreme importance of the existence of a sublingual cavity for the distinctive articulation of sounds.

Distinctive features of sibilants: A closer look

Perkell, Boyce, and Stevens [Speech Communication Papers Presented at the 97th Meeting of the Acoustical Society of America, 109–113 (1979)] emphasized the quantal role of the sublingual cavity in differentiating the noise spectrum of the sibilants [s ∫] in English. Other languages, however, differentiate more than two primary articulatory postures for sibilants. For example, there are three in such languages as Polish, Marathi, and Basque. The greatest number of primary contrastive postures for sibilants appears to be four, as in three Northwest Caucasian languages (Adygbe, Ubykh, and Bzyb). Previously published radiographic tracings for these languages, together with our spectral analyses suggest the need for either a multivalued sublingual cavity feature (nil, small, medium, or large, together with associated frequency characteristics) or additional articulatory distinctions (such as alveolar versus postalveolar and apical versus laminal).