Incomplete Mutation as a Cause of Voice Troubles in Adults

Author’s address: Universiteitskliniek voor Keel-Neusen Oorziekten, Acad. Ziekenhuis Utrecht (Netherlands) It is not unusual that voice mutation at puberty gives rise to some voice trouble for a period of a few weeks or months. It may, however, be the beginning of real disturbances of the voice. Some well known affections are 1) prolonged mutation and 2) persisting falsetto voice. The latter often evokes wrong associations with castration and sexual abnormality. However, the condition is quite different; the growth of the larynx has rendered possible the use of two different registers (chest and falsetto) and for various reasons a boy or man may stick to the wrong one and never discover his chest voice. Therapy, often quick and successful, consists of eliciting the chest voice and making the patient accept its daily use. (Demonstration of tape recordings of patients aged 57, 53 and 17 years.) Less conspicuous, but important because of its frequency, is incomplete mutation. The voice after puberty has lowered a little but it has not reached the full chest volume and quality. This not full-grown type of voice is frequently seen among intellectual people and it is apt to break down under the strain imposed on it by professional use. Often a tense high thoracic type of respiration is found; the laryngeal mirror may show an incomplete closure of the posterior half of the glottis. Stroboscopy reveals a short closure phase of the vibration and a shallow wave-pattern. Voice treatment is necessary to prevent a more severe type of dysphonia or phonasthenia that may follow an incomplete mutation. Even under experienced hands the results of treatment depend a great deal on the patient’s ability to accept a stronger voice and the adult personality it implies.