“…Many physiological factors likely contribute to age-related changes in vocal function, including changes in pulmonary function, neuromuscular properties of intrinsic laryngeal muscles, and the cover of the vocal fold (Awan, 2006;Kahane, 1987;Takeda, Thomas, & Ludlow, 2000). For example, age-related changes within the vocal cover, such as decreases in mass, elastic fibers, and glandular secretions, affect the viscoelasticity properties of the vocal folds in advanced age (65+ years of age) and, thus, affect vocal fold vibration (Bloch & Behrman, 2001;Hirano, Kurita, & Nakashima, 1983;Kahane, 1983;Tomita, Nakashima, Maeda, Umeno, & Sato, 2006). Also, neuromuscular changes of the intrinsic laryngeal muscles likely partially contribute to age-related vocal changes (Connor, Suzuki, Lee, Sewall, & Heisey, 2002;McMullen & Andrade, 2006Suzuki, Connor, Lee, Leverson, & Ford, 2002).…”