Quantifying Tongue Tip Shape in Apical and Laminal /s/: Contributions of Palate Shape

Autor/inn/en	Stone, Maureen; Gomez, Arnold D.; Zhuo, Jiachen; Tchouaga, Ange Lydie; Prince, Jerry L.
Titel	Quantifying Tongue Tip Shape in Apical and Laminal /s/: Contributions of Palate Shape
Quelle	In: Journal of Speech, Language, and Hearing Research, 62 (2019) 9, S.3149-3159 (11 Seiten) PDF als Volltext Verfügbarkeit
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	1092-4388
Schlagwörter	Human Body; Differences; Speech; Computation; Measurement Techniques; Statistical Analysis + Suchen Sie Ihr Suchwort? Menschlicher Körper; Unterscheiden; Speaking; Sprechen; Messtechnik; Statistische Analyse
Abstract	Purpose: Anterior tongue shape during /s/ production is often described as "tip-up" or apical, versus "tipdown" or laminal. Typically, this is determined by observing the shape of the anterior midline tongue. The purpose of this study was to identify methods of curvature calculation that quantify the observed shape differences and to examine whether the shape differences were affected by palate shape. Previous work shows that palate height has some effect (Grimm et al., 2017). Method: Four curvature-based measures were applied to a series of points selected along the tongue surface in midsagittal cine magnetic resonance images during speech. The measures were minimal curvature, averaged largest curvature (ALC), normalized ALC, and interpolated normalized ALC. These measures were compared to visual judgments of apical and laminal /s/. Anterior palate shape was measured from dental casts. Results: The apical /s/ contained a flat or concave region in the anterior tongue, while the laminal /s/ had a convex shape along the entire tongue. Thus, the laminal shape was less complex than the apical. The last 2 metrics, based on averages of multiple normalized curvatures, captured this complexity difference. Subjects with a more steeply sloped anterior palate tended to use laminal /s/. Conclusions: The tongue shape for the 2 /s/ types was best defined by complexity of the shape, rather than local anterior shape. Statistical quantities that measured curvature in multiple locations, and normalized across subjects, were best at distinguishing the 2 /s/ shapes. Interpolating additional points between the manually selected ones did not improve the method. (As Provided).
Anmerkungen	American Speech-Language-Hearing Association. 2200 Research Blvd #250, Rockville, MD 20850. Tel: 301-296-5700; Fax: 301-296-8580; e-mail: slhr@asha.org; Web site: http://jslhr.pubs.asha.org
Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2020/1/01