- 音声言語医学 (ISSN:00302813)
- vol.29, no.2, pp.200-202, 1988-04-25 (Released:2010-06-22)
One of the causes of voice disorder, especially among professional singers or voice students, is overstraining of vocal folds due to improper vocalization, especially breathing. Natural breathing, i.e. inhalation and exhalation, is caused by contraction and relaxation of the diaphragm. For speech or singing, this exhalation has to be done slowly, and in normal speech this is controlled by closing the glottis autmatically and unconsciously. The air pressure and the glottis closure should be well balanced at all times. When a person trys to increase the volume of his voice by stopping the air at the glottis by contracting the vocal folds, the disorder arises. Therefore, the decreasing of the air flow speed must be done solely by the breathing organs themselves. In singing the exhalation can be controlled by the intervention of the muscles used in inhalation, not by closure of the vocal folds alone.The best abdominal exhalation control may be achieved by using the air from the neutral position towards the exhalating direction rather than from the inhalating position to the neutral, and this practice requires special exercise.The exercises should cover three different fields, namely breathing, phonation and articulation. Each exercise should have two parts, recognition and training. The training may be further classfied as partial, co-operative and comprehensive. For example, the contractions and relaxations of both costal and abdominal muscles should first be felt individually and then be trained one after the other separately and co-operatively. Singing /a/ is already considered a comprehensive exercise involving the mustles of costal inhalation, abdominal inhalation and exhalation, laryngeal control muscles, and closing and expanding of the vocal folds.The age and the singing experience of the trained should also be considered.