Modeling and simulation of different vocal fold vibration patterns related to hyperfunctional dysphonic symptoms

Voice plays a crucial role in human communication, any change in voice quality can significantly affect daily interactions including clarity and comfort in speaking. Hyperfunctional dysphonia is a functional voice disorder caused by excessive vocal muscle activity. The vibrations of vocal folds (VFs) are essential for maintaining voice quality, and their kinematic parameters provide valuable insights into voice disorders. This study presents a kinematic model for simulating various VFs vibration patterns associated with hyperfunctional dysphonia. The model evaluates both symmetrical and asymmetrical left–right vibratory phases, providing a visual representation of VFs shape and motion through synthetic kymograms. Validation is performed by comparing these synthetic kymograms with those from previously published studies, using error metrics based on glottis area differences, Structural Similarity Index Measure (SSIM), and Oriented Fast Rotated Brief (ORB) similarity metrics. Each technique is applied to four different phonation types with varying initial oscillation phase values. Results indicate that the proposed model achieves low error value in the first validation technique, with minimum and maximum error values of 0 and 0.0005 for symmetry, and 0.00035 and 0.0932 for asymmetry, respectively. Furthermore, it demonstrates strong similarity between the second and third validation techniques, with maximum and minimum similarity values of 1 and 0.857 for symmetry, and 1 and 0.70393 for asymmetry, respectively. This model enhances the understanding of mucosal wave (MW) dynamics and improves the diagnostic capabilities for hyperfunctional dysphonia in kymographic imaging. By offering more comprehensive view of VFs motion, it facilitates better interpretation of the diverse features relevant to diagnosing hyperfunctional dysphonia.