Oliveira et al.(1111 Oliveira KGSC, Lira ZS, Silva HJ, Lucena JA, Gomes AOC. Oropharyngeal geometry and the singing voice: immediate effect of two semi-occluded vocal tract exercises. J Voice. 2022 Jul;36(4):523-30. http://dx.doi.org/10.1016/J.JVOICE.2020.06.027. PMid:32712077. http://dx.doi.org/10.1016/J.JVOICE.2020....
) (2020) |
AP |
Assessment of the effect of vocal techniques on VT. |
Oral cavity length and volume, pharyngeal cavity length and volume, VT length and volume, oropharyngeal junction area, and glottal area. |
VT length was greater in the group that used FRT than in those who performed VLVT. Also, GNE improved, and noise decreased, only in the group of singers submitted to VLVT. |
Unteregger et al.(1919 Unteregger F, Wagner P, Honegger F, Potthast S, Zwicky S, Storck C. Changes in vocal fold morphology during singing over two octaves. J Voice. 2020;34(2):165-9. http://dx.doi.org/10.1016/j.jvoice.2018.08.020. PMid:30266281. http://dx.doi.org/10.1016/j.jvoice.2018....
) (2020) |
CT scan |
Study of VF morphological changes. |
VF angle. |
Results suggest that TA has greater action during emission in f0 than in 2f0, as the VF angle is greater in f0. The CT muscle contracts and VF is thinner in 2f0; however, CT contraction is maintained, and the VF angle increases in 4f0, which suggests TA action to maintain subglottal pressure at higher frequencies. |
Berdan et al.(2424 Berdan M, Petekkaya E, Yücel AH. Effect of chant training on the morphology of the lateral thyrohyoid ligament: a biometric and acoustic assessment. J Voice. 2019;33(5):802.e17-23. http://dx.doi.org/10.1016/j.jvoice.2018.04.014. PMid:30121143. http://dx.doi.org/10.1016/j.jvoice.2018....
) (2019) |
MRI |
LTL measurement |
LTL |
LTL length was greater in men. This finding confirms specific laryngeal structure differences between the sexes. Vocal training time did not make a difference in LTL in the groups; the acoustic voice analysis improved in the group with vocal training. |
Nair et al.(2727 Nair A, Nair G, Reishofer G. The low mandible maneuver and its resonential implications for elite singers. J Voice. 2016;30(1):128.e13-32. http://dx.doi.org/10.1016/j.jvoice.2015.03.010. PMid:26474717. http://dx.doi.org/10.1016/j.jvoice.2015....
) (2016) |
MRI and ultrasound |
Measurement of the extent of mandible drop in a singing maneuver. |
The extent of mandible drop. |
The extent of mandible drop in MLM ranged from 0.7 to 3.1 cm, which increased the first harmonics and improved the singer’s formant. |
Roers et al.(1414 Roers F, Mürbe D, Sundberg J. Voice classification and vocal tract of singers: a study of x-ray images and morphology. J Acoust Soc Am. 2009;125(1):503-12. http://dx.doi.org/10.1121/1.3026326. PMid:19173435. http://dx.doi.org/10.1121/1.3026326...
) (2009) |
X-ray |
VF length measurement. |
Subglottal-tracheal anteroposterior distance and VF anterior end distance. |
Morphological measures in the X-ray of TS (between the thyroid cartilage and the anterior contour of the nearest cervical vertebra) and STAP distances (anteroposterior diameter of the subglottal and tracheal contour) are correlated with VF length. There was a covariation between VF length measured in X-ray and vocal classifications. |
Mainka et al.(2626 Mainka A, Poznyakovskiy A, Platzek I, Fleischer M, Sundberg J, Mürbe D. Lower vocal tract morphologic adjustments are relevant for voice timbre in singing. PLoS One. 2015;10(7):e0132241. http://dx.doi.org/10.1371/journal.pone.0132241. PMid:26186691. http://dx.doi.org/10.1371/journal.pone.0...
) (2015) |
MRI |
VT assessment in German vowel emission in singing. |
Laryngeal height, endolaryngeal area and volume, hypopharyngeal area and volume. |
Singing vowels, in contrast with speech vowels, were produced with lowered larynx, greater cross-sectional area and lower hypopharyngeal volume, and smaller proportion of the laryngeal-hypopharyngeal area and volume. There was a significant variance of all lower VT measures with vowel quality. Combined lowered larynx and widened hypopharynx were found in vowels /o/ and /u/ emitted in singing. Acoustically, there was an increase in high-frequency energy when singing above 2 kHz, correlated with a broader hypopharyngeal area. There was also evidence that the fourth formant displaced down with lower VT structures in the singing configuration. |
Mainka et al.(2929 Mainka A, Platzek I, Mattheus W, Fleischer M, Müller A-S, Mürbe D. Three- dimensional vocal tract morphology based on multiple magnetic resonance images is highly reproducible during sustained phonation. J Voice. 2017;31(4):504.e11-20. http://dx.doi.org/10.1016/j.jvoice.2016.11.009. PMid:27988067. http://dx.doi.org/10.1016/j.jvoice.2016....
) (2017) |
MRI |
Assessment of volume and area of VT segments. |
Oral cavity volume and area, oropharyngeal volume and area, hypopharyngeal volume and area, and endolaryngeal volume and area. |
Morphological data based on multiple images with the segmentation model were highly reproducible, with an overall variation of around 8%. 3D data on VT morphology based on various MRI images during phonation can be generated with high precision in experienced singers. |
Echternach et al.(3030 Echternach M, Traser L, Richter B. Vocal Tract Configurations in Tenors’ Passaggio in different vowel conditions: a real-time magnetic resonance imaging study. J Voice. 2014;28(2):262.e1-8. http://dx.doi.org/10.1016/j.jvoice.2013.10.009. PMid:24412038. http://dx.doi.org/10.1016/j.jvoice.2013....
) (2014) |
MRI |
Analysis of the influence of vocal conditions on VT. |
Lip opening, tongue dorsum, mandible opening and protrusion, pharyngeal width, uvula length, and laryngeal position and angle. |
Falsetto after the passage note was performed with similar VT shapes in the various vowels emitted. However, some articulators, such as pharyngeal width, changes along with the vowels. |
Clarós et al.(2121 Clarós P, Sobolewska AZ, Doménech-clarós A, Clarós-pujol A, Pujol C, Clarós A. CT-based morphometric analysis of professional opera Singers’ Vocal Folds. J Voice. 2019;33(4):583.e1-8. http://dx.doi.org/10.1016/j.jvoice.2018.02.010. PMid:29573873. http://dx.doi.org/10.1016/j.jvoice.2018....
) (2019) |
CT scan |
Relationship between VF length and classical voice types. |
VF length |
The analysis confirmed a linear correlation between VF length and individual body characteristics, such as height and body mass index. |
Traser et al.(1212 Traser L, Burdumy M, Richter B, Vicari M, Echternach M. Imaging as an option in the study of gravitational effects on the vocal tract of untrained subjects in singing phonation. PLoS One. 2014;9(11):e112405. http://dx.doi.org/10.1371/journal.pone.0112405. PMid:25379885. http://dx.doi.org/10.1371/journal.pone.0...
) (2014) |
MRI |
Observation of VT morphological differences in relation to body supine and erect positions. |
Lip opening, mandible opening and protrusion, the distance between the tip of the tongue and the hard palate, oropharyngeal width, uvula elevation, and laryngeal vertical position and tilt angle. |
There are few VT configuration differences between the positions analyzed. VT changes associated with register and tuning are not much affected by the position. |
Echternach et al.(2828 Echternach M, Sundberg J, Baumann T, Markl M, Richter B. Vocal tract area functions and formant frequencies in opera tenors’ modal and falsetto registers. J Acoust Soc Am. 2011;129(6):3955-63. http://dx.doi.org/10.1121/1.3589249. PMid:21682417. http://dx.doi.org/10.1121/1.3589249...
) (2011) |
MRI |
Analysis of VT area in tenors. |
VT area. |
VT shapes in vowel /a/ differ between the modal register and falsetto. The oral cavity was wider in the modal register. Moreover, F1 was greater in the modal register than in the falsetto. |
Andrade(2525 Andrade PA. Analysis of male singers laryngeal vertical displacement during the first passaggio and its implications on the vocal folds vibratory pattern. J Voice. 2012;26(5):665.e19-24. http://dx.doi.org/10.1016/j.jvoice.2011.10.006. PMid:22578439. http://dx.doi.org/10.1016/j.jvoice.2011....
) (2012) |
EGG |
Implications of the passagio to VT morphology. |
VT length. |
Western classical singers tend to lower the larynx in the neck after the passage, thickening the VF, reducing central formant frequencies, and thus increasing supraglottal cavities. |