Summary This study, focused on the laryngeal source level, introduces the concept of laryngeal vibratory mechanism. Human phonation is characterized by the use of four laryngeal mechanisms, labeled ...M0–M3, as evidenced by the electroglottographic (EGG) study of the transition phenomena between mechanisms with a population of men and women, trained and untrained singers. Macroscopic and local descriptions of the EGG signal are analyzed during the production of glissandos and held notes with different mechanisms. The transition from one mechanism to another of higher rank is characterized by a jump in frequency, a reduction of EGG amplitude, and a change in the shape of the derivative of the EGG (which may correspond to a reduction of the vibratory mass). These characteristics are used to identify a transition between two mechanisms, in complement with acoustic spectrographic analyses. The pitches of transitions between the two main mechanisms M1 and M2 and the range of the frequency-overlap region are described in detail. The notion of vocal register is revisited in the light of these concepts of laryngeal mechanism. The literature on vocal registers is reviewed, and it is shown that the confusion often cited with respect to this notion may be related to the heterogeneity of the approaches and methods used to describe the phenomena and to the multiplicity of descriptors. Therefore, the terminology of the registers is organized depending on their relation to the four laryngeal vibratory mechanisms.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Distinction between unilateral recurrent laryngeal nerve paralysis and Xth nerve paralysis is a rarely addressed issue in the literature. However, it may be crucial to examine the cause of the ...paralysis and to perform the appropriate investigation. The videoendoscopic swallowing study has been demonstrated to be a useful tool in assessing pharyngeal function. Since in unilateral Xth nerve paralysis the pharynx is impaired on the same side as the vocal fold immobility, it may be easily detected by videoendoscopic swallowing study. The rotation of the posterolateral pharyngeal wall toward the opposite side during swallowing is a sign of impaired motor pharyngeal branches. To demonstrate the usefulness of the videoendoscopic swallowing study in distinguishing unilateral Xth nerve from isolated recurrent nerve paralysis, a series of six patients were studied prospectively. Diagnosis of Xth nerve paralysis focused the investigation toward the high neck or the skull base area. Paralysis of the Xth nerve was suspected in all cases and diagnosis was achieved in five cases by the workup performed. Videoendoscopic swallowing study is a cost-effective and easily available tool which should be performed in all cases of vocal fold paralysis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Roubeau B, Chevrie-Muller C, Lacau St Guily J. Electromygraphic activity of strap and cricothyroid muscles in pitch change. Acta Otolaryngol (Stockh) 1997; 117: 459-464.
The EMG activity of the ...cricothyroid muscle (CT) and the three extrinsic laryngeal muscles (thyohyoid, TH; sternothyroid, ST, and sternohyoid, SH) were recorded throughout the voice range of one female and one male subject, both untrained singers. The voice range was examined using rising and falling glissandos (production of a sustained sound with progressive and continuous variation of fundamental frequency). Muscle activity was observed at various pitches during the glissandos. The strap muscle activity during the production of glissandos appears to be synergistic. At the lowest frequency, the CT is inactive but strap muscles (TH, ST, SH) are active. As frequency increases, strap muscle activity decreases while the CT controls frequency in the middle of the range. At higher frequencies the strap muscles once again become active. This activity might depend on the vocal vibratory mechanism involved. The role of the strap muscles at high pitches is a widely debated point but it seems that in some way they control the phenomena relevant to the rising pitch. The phasic-type strap muscle activity contrasts with the tonic-type activity of the CT. The CT closely controls the frequency, while the straps are not directly linked to the pitch but rather to the evolution of the frequency of voice production (speaking voice, singing voice, held notes, glissandos, trillo, vibrato, etc.).
Electrical stimulation of the superior laryngeal nerve (SLN) can elicit reflex responses in the cricothyroid (CT) and thyroarytenoid (TA) muscles. We made bilateral recordings of the responses evoked ...in these muscles in piglets by the stimulation of either the right or the left superior laryngeal nerve (SLN). The stimulus intensity was gradually increased to study the ?persistence? of the responses. We observed a direct, ipsilateral response in the CT muscle, and reflex, ipsilateral and crossed responses in both CT and TA muscles. The ipsilateral or contralateral responses obtained in TA muscles, following stimulation of the left SLN, were significantly delayed in comparison with those evoked by stimulation of the right SLN. This delay cannot be explained by the difference in length between the right and the left recurrent laryngeal nerves, but rather by an asymmetry in the sensory afferent pathway. The functional significance of this observation remains to be determined.
This study was performed to establish the swallowing trigger by using the reaction time from an auditory stimulus. With this stable temporal starting point, we described the chronology of the ...different acoustic, electrophysiologic, and respiratory events that occurred during swallowing in a population of normal adults. We studied the swallowing reaction time (SRT) in 18 subjects aged 23 to 73 years by using acoustic, electroglottographic (EGG), and aerodynamic recordings. The chronology (the beginning of EGG activity, apnea, and respiratory sound and release) was identified in 91% of the recordings. The average SRT was 264 ms and the average swallowing duration was 977 ms, without any significant difference with respect to gender. The swallowing sound produced during apnea was composed of either two or three components. The reaction time procedure also demonstrated that the first sound component was unstable. By using this procedure for studying swallowing, we were able to stabilize the chronology of the different events, improve the subjects’ attention, and establish a fixed benchmark for performing temporal measurements.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Le phonétogramme par registre (ou mécanisme vibratoire laryngé) résulte de la superposition de deux phonétogrammes élaborés séparément pour chacun des deux principaux registres vocaux. Il permet ...d’évaluer l’ensemble des possibilités de la voix suivant les deux axes amplitude et fréquence, en rendant compte des possibilités inhérentes à chaque mécanisme. Cette technique permet de mieux comprendre l’influence des zones de passage sur l’aspect général du tracé. Le calcul de l’aire des phonétogrammes par registre laryngé, appliqué à une population de 42 sujets issus de trois catégories: non-chanteurs, chanteurs amateurs et chanteurs confirmés des deux sexes, met en évidence le rôle de la technique vocale sur les potentialités acoustiques du vibrateur laryngé. Enfin, cette approche fournit des informations complémentaires précieuses pour la connaissance des registres vocaux.
A prospective study was performed on 18 adults to analyze disturbances of voice and respiratory function in unilateral vocal fold paralysis and the role of medialization in the improvement of breath ...control. In addition to physical examination, an acoustic and aerodynamic analysis, as well as patient self-assessment, were performed both before and after medialization (14 fat injections, 4 thyroplasties) to evaluate voice and both phonatory breath control and respiratory function outcome. Preoperative and postoperative results, at short, middle, and long term, were compared to data from 14 control subjects and evaluated by statistical analysis. Preoperative acoustic and aerodynamic parameters were significantly disturbed in comparison to controls. Independently of the pulmonary status, medialization induced an improvement in most of the parameters at short and long terms, whereas a diminished effect was observed at middle term. Phonatory breath control, as evaluated by maximum phonation time, mean flow rate, and expired volume, was statistically improved, with the best results being obtained in women. From the questionnaire, it was clear that voice, as well as phonatory breath control and respiratory function, showed considerable improvement, although some difficulties persisted during effort. This study demonstrates that there is a disturbance of phonatory breath control and respiratory function in adult unilateral vocal fold paralysis. Improvement following medialization supports the concept that the respiratory dysfunction seen beforehand is most probably the result of air escape rather than laryngeal obstruction. Although medialization may provoke an extrathoracic obstruction, its feature of variability appears to improve breath control.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
Two phonetograms prepared separately for each of the two principal vocal registers or laryngeal vibratory mechanisms are superimposed to produce a register phonetogram, which makes it possible to ...assess the full voice-range profile along the two axes of amplitude & frequency while accounting for the inherent possibilities of each mechanism. This technique improves understanding of the influence of zones of passage on the general conformation of the voice trace. An area calculation of laryngeal register phonetograms is applied to a population (N = 42) of both sexes taken from three categories: nonsingers, amateur singers, & professional singers. Results provide evidence of the role of vocal technique on the acoustic potential of the laryngeal vibrator; this approach furnishes valuable complementary information on vocal registers. 8 Tables, 6 Figures, 33 References. Adapted from the source document
Voice range profile (VRP) is a well-known vocal test. Usually, it consists of a single diagram based on the whole voice range. When practised separately in each individual laryngeal mechanism, VRP ...may offer much information on both the relative development of the different mechanisms used by the subject and the extension of the common area between two consecutive mechanisms. We present the results obtained from 42 subjects of both sexes who have different singing technique levels: professional singers, student and amateur singers, as well as subjects without any experience in singing. For each mechanism, the global VRP area and the dynamic range were computed. Results are discussed in relation to sex category and vocal training of subjects. Exploring systematically VRP for each mechanism gives new and valuable information on register managing in singing practice.
