Ventricular-fold dynamics in human phonation

Purpose: In this study, the authors aimed (a) to provide a
classification of the ventricular-fold dynamics during voicing,
(b) to study the aerodynamic impact of these motions on
vocal-fold vibrations, and (c) to assess whether ventricularfold
oscillations could be sustained by aerodynamic coupling
with the vocal folds.
Method: A 72-sample database of vocal gestures
accompanying different acoustical events comprised highspeed
cinematographic, audio, and electroglottographic
recordings of 5 subjects. Combining the physiological correlates
with a theoretical model of phonation, the vocal–ventricular
aerodynamic interactions were investigated.
Results: A ventricular-fold motion is found during
(de)crescendos, shout, throat singing, yodel, growls, and
glides with transitions between registers. Three main types
of dynamics are identified: slow nonoscillatory motion and
fast oscillatory motion with aperiodical or periodical vibrations.
These patterns accompany a change in voice quality, pitch,
and/or intensity. Alterations of glottal-oscillatory amplitude,
frequency, and contact were predicted. It is shown that a
ventricular oscillation can be initiated and sustained by
aerodynamic coupling with the vocal folds.
Conclusions: Vocal–ventricular aerodynamic interactions
can alter, enhance, or suppress vocal-fold vibrations or
leave them unchanged, depending on the ventricular-fold
dynamics involved. Depending on its variation in time, a
similar level of ventricular-fold adduction impacts the glottal
vibratory magnitude and contact much differently.