Glottal Changes Research Articles

Distinct Acoustic Features and Glottal Changes Define Two Modes of Singing in Peking Opera

We aimed to delineate the acoustic characteristics of the Laodan and Qingyi role in Peking Opera and define glottis closure states and mucosal wave changes during singing in the two roles. The range of singing in A4 (440 Hz) pitch in seven female Peking Opera singers was determined using two classic pieces of Peking Opera. Glottal changes during singing were examined by stroboscopic laryngoscope. The fundamental frequency of /i/ in the first 15 seconds of the two pieces and the /i/ pitch range were determined. The relative length of the glottis fissure and the relative maximum mucosal amplitude were calculated. Qingyi had significantly higher mean fundamental frequency than Laodan. The long-term average spectrum showed an obvious formant cluster near 3000 Hz in Laodan versus Qingyi. No formant cluster was observed in singing in the regular mode. Strobe laryngoscopy showed complete glottal closure in Laodan and incomplete glottal closure in Qingyi in the maximal glottis closure phase. The relative length of the glottis fissure of Laodan was significantly lower than that of Qingyi in the singing mode. The relative maximum mucosal amplitude of Qingyi was significantly lower than that of Laodan. The Laodan role and the Qingyi role in Peking Opera sing in a fundamental frequency range compatible with the respective use of da sang (big voice) and xiao sang (small voice). The morphological patterns of glottal changes also indicate that the Laodan role and the Qingyi role sing with da sang and xiao sang, respectively.

Glottal motion and its impact on the respiratory flow

The aim of this study was (i) to characterise the glottal dynamics during human breathing in vivo using laryngofiberscopy and synchronised airflow recordings and (ii) to quantify the effects of a mobile glottis and unsteady flow conditions on laryngeal jet-flow dynamics using CFD modelling. The in vivo study showed that the glottis can be extremely variable during breathing and hence influence airflow characteristics. A glottal area widening was quantified during inspiration, with a typical ratio of 3:1 as compared to expiration. Airflow rate variations differ from harmonic signal during eupnea as well as tachypnea. The correlation between flow-rate and glottal area will be discussed and compared to previous clinical investigations. Preliminary 2D CFD simulations of the glottal jet were carried out based on the measured flow-rate and glottal changes during eupnea. Impact of unsteady flow conditions on the jet development is demonstrated.

Hoarseness, Articulation Disorder and Hearing Impairment in Subjects with Hypothyroidism

Thyroid hormones target cardiovascular, neuromuscular, digestive, and metabolic systems, meaning that hypothyroidism may cause a wide variety of symptoms. Hypothyroidism is usually characterized by struma and myxedema. The absence of struma, however, may cause hypothyroidism to be mistaken for other organ disorders or normal aging-associated change. We report 2 cases of hypothyroidism without struma. Case 1 was a 76-year-old man seen for postnasal drip and ear stuffiness complicated by myocardial infarction, kidney dysfunction, and abnormally high CK. Case 2 was an 83-year-old man seen for prolonged dizziness, who also had heart failure and generalized edema. Neither patients responded well to a treatment and showed deteriorating truncal ataxia, increasing body weight, bradykinesia, bradyarthria, hoarseness, and impaired hearing. Case 2, also had edematous glottal change. Although no struma was seen, thyroid hormone levels were measured to determine the cause of hoarseness, showing high TSH and low fT3 and fT4 level. Case 1 was diagnosed with primary hypothyroidism, and Case 2 with secondary hypothyroidism. Hormonal therapy induced improvements in impaired hearing, previously considered a sign of aging, and in bradykinesia, truncal ataxia, and hoarseness. Hoarseness and bradyarthria were relieved regardless of glottal edema. Internal complications were also markedly alleviated. In case 1, impaired hearing worsened again after the mean stopped taking vitamin B12, but improved again when vitamin B12 was restarted. Articulation disorder in hypothyroidism presumably involves neuropathy and affecting from speech center to articulatory organs, including the glottis. Impaired hearing also presumably is caused by the same neuropathy depending on the vitamin B12 level.