MadSci Network: Medicine |
This generally results from natural aging of the vocal apparatus. The following is summarized from a very good review article: www.findarticles.com/m2578/n7_v53/20999024/p1/article.jhtml Voice results from the interaction of many organs, starting with the diaphram and respiratory muscles, and ending with the lips. The lungs generate the exhaled breath. The larynz--which contains the vocal cords-- regulates the airflow and vibrates to provide the frequency of sound. The volume of the pharynx, oral and nasal cavities act as resonators. The tongue and the lips provide articulation. A change in any part of this system will alter speech. The article lists a number of normal changes: 1. Decrease in breath support. 2. Laryngeal changes: a. Ossification of the laryngeal cartilage and joints b. Loss of vocal cord bulk 3. Specific Vocal Cord Change: The article lists as the probable most benign change as "bowing" of the vocal cords. This results from an inability to fully close the middle third of gap between the cords. 4. Cricoarytenoid Joint Arthritis: The joint surface may become uneven and its collagen fibers disorganized. The arytenoid cartillage fine-tunes the pitch, and these changes may account for the pitch variability observed with age. The vocal cords in men thin and atrophy with age, resulting in a higher pitched conversational voice. The vocal cords in women may become thicker after menopause resulting in a lower pitched voice. Interestingly, the article notes that some of the changes can result from patients attempts to compensate for these changes. Men may develop the "gravelly" voice in an attempt to lower the pitch. Pathologic changes occur as well. The article reviews them nicely. --Doctor X Ref: Sinard, Robert J., The Aging Voice: How to Differentiate Disease from Normal Changes.
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