Pathological voice production by mechanical vocal cord model

Pathological vocal cord vibration was examined by using a mechanical vocal cord model (Fukui and Honda, ISSP-08). The previous model was modified for producing the pathological vocal cord vibration. It has independent mechanism for the cord tension and the glottal opening of the left and the right vocal folds. Also, the vocal folds with asymmetric shapes were formed as well as the symmetric type. By using the modified vocal cord model, pathological vocal cord vibration was produced. The vocal cord vibration was measured by high speed video camera and was analyzed by using kymograph. The experimental results showed that the vocal cord vibration was changing from a single pitch vibration to a double or triple pitch vibration as the control was changing from the balanced to the unbalanced form. The vocal cord vibration patters were examined for various combinations of balanced and unbalanced vocal cord control parameters and for symmetric and asymmetric vocal folds models.