Roentgenological observations on vocal fold length-changes with special reference to register transition and open/covered voice

Effects of length and depth of vibration of the vocal folds on the relationship between transglottal pressure and fundamental frequency of phonation in canine larynges

The relationship between fundamental frequency of phonation (F0) and the change in F0 per unit change of transglottal pressure (dF/dP) was investigated in 3 excised canine larynges. The effects of the length and depth of vocal fold vibration on the relationship between dF/dP and F0 were evaluated. A positive correlation between dF/dP and F0 was observed when an increase in F0 was accompanied by a decrease in the depth of vibration while the length of vibration reached a plateau. Although a negative correlation between dF/dP and F0 was observed in only 1 case, this relationship seemed relevant to the length of vibration. These results help to clarify the adjustments of length and depth of vibration involved in regulating F0.

The external frame function in the control of pitch, register, and singing mode: radiographic observations of a female singer

This study investigates pitch control, register, and singing mode related movements of the laryngo-pharyngeal structures by radiographic methods. One trained female singer served as the subject. The results show that singing voice production involves complex movements in the laryngeal structures. Pitch related increase in the thyro-arytenoid distance (vocal fold length) is nonlinear, slowing down as pitch rises. Similar observations have been made earlier. At the highest pitches, a shortening of the distance can be seen, suggesting the use of alternative pitch control mechanisms. The various observations made support the existence of three registers in this trained female singing voice. Open and covered modes of singing seemed to be distinguishable on the basis of different amounts of inner and outer forces acting on the larynx. Therefore, caution must be exercised when generalizing from the results.

External laryngeal frame function in voice production revisited: a review

Research indicates significant contribution of extrinsic laryngeal mechanisms to voice production. This article reviews the major theories of the role of the external laryngeal factors in voice production and relevant experimental data. The review suggests that partly neglected external factors and possibly even misinterpretation of some of the recently documented individual variation in physiological data may have unnecessarily complicated the issues pertaining to the interplay between the physiological mechanisms of the larynx. The implications of contemporary findings and documentation in the modeling of the extrinsic factors are discussed and a synthesis of empirical data into two simple models of the extrinsic forces of pitch control is presented. Also suggested by the review, a basic principle, probably underlying the laryngeal control of phonation, is put forward.

Vocal-fold collision mass as a differentiator between registers in the low-pitch range

Register shift between the chest and falsetto register is generally studied in the higher-than-speaking pitch range. However, a similar difference can also be produced at speaking pitch level. The shift from breathy "falsetto" phonation to normal chest voice phonation was studied in normal female (pitch range 170-180 Hz) and male (pitch range 94-110 Hz) subjects. The phonations gliding from falsetto to normal chest voice were analyzed using iterative adaptive inverse filtering and electroglottography. Both trained and untrained, as well as female and male subjects, were able to produce an abrupt register shift from soft falsetto to soft chest register phonation. The differences between male and female speakers in the glottal flow waveforms were smaller than expected. The register shift is interpreted in terms of a "critical mass" concept of chest register phonation.