“…Specifically, the vocal folds may thicken, the superficial layer of the lamina propria may become thinner and/or more oedematous, and the vocalis muscle may atrophy. The main effect on the voice is a change in vocal range, with progressive loss of top voice, expansion of lower voice, and reduction in total voice range (Mueller, et al, 1984;Linville, 1987;Sataloff, et al, 1997;Teles-Magalhães et al, 2000;Verdonck-de Leeuw & Mahieu, 2004). Other effects of aging include a deterioration in vocal quality, abnormal vibration of the vocal folds, reduction in the control of pitch, a marked decrease in vocal agility, reduced responsiveness between nerve impulses and muscle fibres (adversely affecting the cricothyroid and thyroarytenoid muscles), a decrease in glottal firmness and reduced elasticity of the vocal folds.…”