A model for vocal fold vibratory motion, contact area, and the electroglottogram

Area of Science:

• Laryngology and Voice Science
• Bioacoustics
• Biomechanical Modeling

Background:

• The electroglottogram (EGG) is a non-invasive measure of vocal fold vibration.
• Its precise relationship to vocal fold contact area remains incompletely understood.
• Previous studies offer partial substantiation through direct and indirect observations.

Purpose of the Study:

• To develop and validate a simple biomechanical model for estimating vocal fold contact area during vibration.
• To simulate electroglottogram (EGG) waveforms based on the estimated contact area.
• To compare simulated EGGs with measured EGGs from normal and pathological voice production.

Main Methods:

• Utilized ultra high-speed laryngeal films to extract key vocal fold vibratory features.
• Included vocal fold opening/closing angles and phase lag between upper/lower margins in the model.
• Simulated EGG waveforms using the derived contact area function.
• Compared model predictions against measured EGGs for modal and pulse register tones in male voices.

Main Results:

• The developed model successfully estimated vocal fold contact area over time.
• Simulated EGG waveforms showed good agreement with measured EGGs for normal voice registers.
• The model demonstrated potential in predicting EGG patterns associated with vocal fold nodules or polyps.

Conclusions:

• The study provides a validated model linking vocal fold vibratory mechanics to electroglottogram signals.
• This model advances the understanding of EGG as a measure of vocal fold contact area.
• The approach shows promise for non-invasive voice disorder assessment and analysis.