Possible Influences of Vowel Tongue Position on Vocal Fold Stiffness

The purpose of this investigation was to examine the effect of tongue position on vocal fold stiffness. New aerodynamic measures were used to estimate vocal fold stiffness during sustained productions of the vowels [i], [^], and [a]. Those measures were acoustic oscillation damping time, acoustic oscillation threshold pressure, vocal fold oscillation damping time, and vocal fold oscillation threshold pressure. The subject\u27s oral airflow was interrupted with a shutter-valve during vowel productions. Significant differences were found in each of four criterion measures. The trends found supported the hypothesis that vocal fold stiffness decreased from [i] to [^] to [a]. The possibility of the results being obtained due to upper airway stiffness or oral-pharyngeal resistance (as opposed to vocal fold stiffness alone) was considered and discussed