Vocal Folds

Growth

As a classical singer, vocal polyp growth is a frightening yet all too real risk of my hobby. Vocal polyps grow when the vocal folds beat as a result of extensive abuse of the vocal folds, such as by yelling, singing, or talking loudly and for extending periods of time. I developed a model of vocal polyp growth, predicting the magnitude of forces and duration of time required to cause initial polyp growth. Once a polyp begins to grow, polyps grow exponentially due to larger surface area interfering with the natural motion of the vocal folds.

Vibration

Years later I revisited vocal fold modeling to look at vocal fold motion. For this project, I studied 1-dimensional motion of the vocal folds in the transverse plane of the larynx. Building on existing models that examine motion in the frontal plane of the body, this model provides a different perspective on vocal fold motion crucial for building patient-specific diagnostic tool. The Symmetric and Asymmetric Motion videos below are described by 1D equations of motion and solved by MATLAB’s ODE solver ODE 45.

The approximated 1D wave equation model is an attempt to describe vocal fold motion via the 1D wave equation. This model assumes the edges of the vocal folds move like a 1D vibrating string or membrane. In this model, the 1D wave equation is solved via d’Alambert’s solution to the 1D wave equation using the finite difference method. This model presents a decent approximation of the motion and may be a valuable approximation for fast simulation of vocal fold motion. You can view the presentation for this project here.

References

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