BIFURCATIONS IN A VOCAL FOLD MODEL

An autonomous fourth order model of vocal fold vibrations is proposed. Each fold is represented by a lower and upper mass, and the aerodynam ic forces are derived from a modified Bernoulli equation. The model ex hibits many features of normal phonation in a wide parameter region. A t the borderlines of this region coexistence of limit cycles, period-d oubling and chaos are observed. Implications for an understanding of p athological voices are discussed.