ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

4aSC23. Correlating movement and acoustic measures of nasalization.

Res. Lab. of Electron., Rm. 36-511, MIT, Cambridge, MA 02139

Rena A. Krakow

Temple Univ., Philadelphia, PA 19122

Haskins Labs., New Haven, CT

Previous research using physiological instrumentation (e.g., Velotrace) has shown systematic effects of syllable structure and stress on velum movements [Krakow, in Phonetics and Phonology V (Nasals, Nasalization, and the Velum, edited by Huffmann and Krakow (Academic, San Diego, 1993), pp. 87--113]. However, what has not been investigated previously is the correspondence between the time-varying position of the velum in such data and the timing and magnitude of acoustically detectable nasalization. A new technique developed by Chen [ 3283 (A) (1994)] for identifying the spectral effects of nasal coupling was found to provide a valuable way of linking the acoustic and articulatory changes related to velopharyngeal port aperture. This paper reports on acoustic-to-articulatory mapping using acoustic data collected in concert with Velotrace data for a number of different utterance types, including those with stressed versus unstressed syllables and those with syllable-initial versus syllable-final nasals. One consistent observation is that velum lowering can be quite extensive before acoustic effects are observed. [Work supported in part by NIH.]