2pSC1. The phonatory pressure-flow-adduction space.

Session: Tuesday Afternoon, December 3

Time: 4:55

Author: Ronald C. Scherer
Location: Dept. of Commun. Disord., Bowling Green State Univ., Bowling Green, OH 43403
Author: Fariborz Alipour
Location: Univ. of Iowa, Iowa City, IO 52242
Author: Chwen G. Guo
Location: Denver Ctr. for the Performing Arts, Denver, CO 80236


Relationships among average subglottal pressure, average glottal airflow, and glottal adduction (vocal process gap), variables related to glottal competence, were obtained for one human subject. The data define the pressure-flow-adduction space. Results are similar to those of a study using excised canine larynges [Alipour et al., ``Pressure-flow relationships during phonation as a function of adduction,'' J. Voice (in press)] especially for the differential flow resistance as a function of adduction. For set values of adduction, glottal flow resistance increased by about 2.5 times between subglottal pressure values of 5 and 15 cm H[inf 2]O. At set values of subglottal pressure, flow resistance increased by a factor of approximately 9.5 between pressed and breathy phonation. Any particular flow resistance value does not predict a particular adduction value due to the dependence on subglottal pressure. However, a particular subglottal pressure, glottal flow pair appears to predict a particular adduction level. Subglottal aerodynamic power increases with subglottal pressure at set levels of adduction, increasing by a factor of about 3.7 between 5 and 15 cm H[inf 2]O. For a specific value of subglottal pressure, aerodynamic power increases as adduction decreases. [Work supported by NIH Grant No. P60 DC00976.]

ASA 132nd meeting - Hawaii, December 1996