Modal Phonation Research Articles

Discriminant analysis of acoustic cues to three Green Mong tones

Green Mong is a tone language with an inventory of seven contrastive tones. The tonal system of Green Mong incorporates both pitch and phonation-type distinctions, and appears to make use of many of the acoustic parameters which have been shown to correlate with phonation-type cross-linguistically. This study looks at three Green Mong tones that have similar pitch contours, but are distinguished by the distinctive use of breathy, creaky, and modal phonation. Acoustically, the three tones are distinguished to some degree on the basis of pitch, relative amplitude of lower and higher harmonics (H1–H2), duration, vowel quality, and voice onset time. Discriminant analysis is used to estimate the value of these different cues for classifying tokens into tone categories based on observed characteristics in tone production. Discriminant functions were generated using measurements from 270 CV words produced by six speakers, for which every combination of three vowels (/i/, /u/, /a/) five consonants, and three tones (breathy, creaky, modal) was attested. Results of the analyses will be presented, as well as results for classification of a separate, test set of 102 CV tokens produced by the same six speakers.

Lead Article: An Intuitive Vocal Fold Functional Model for Modal Voice Phonation for Use in the ENT Voice Clinic

Routine voice assessment by acoustic analysis can be of substantial value to clinical examination in the ear, nose, and throat (ENT) voice clinic. Improved functional diagnosis, more informative patient records, accurate assessment of patient progress and better clinical team liaison are but a few of the benefits realised over a decade of work in the Edinburgh voice clinic. To obtain these advantages through instrumental voice assessment, it is important to have a thorough understanding of what is being measured and the reason behind the measurement. It is also vital to remember that acoustic measurements can be directly related to vocal fold function but not necessarily to pathology. To interpret analysis results, it is therefore important to possess a functional model for vocal fold phonation which relates vocal fold mechanics to what is seen, heard, and measured in the voice clinic.This article describes vocal fold function using intuitive concepts which have assisted the multidisciplinary voice clinic...

Commentaries: the Usefulness and Applicability of the Intuitive Vocal Fold Functional Model for Modal Voice Phonation in the Voice Clinic

Commentaries: the Usefulness and Applicability of the Intuitive Vocal Fold Functional Model for Modal Voice Phonation in the Voice Clinic

Pitch discrimination during breathy versus modal phonation (final results)

This study completes an investigatation of pitch discrimination during breathy phonation versus modal phonation by manipulating acoustic parameters. Both breathy vowels and modal vowels from Jalapa Mazatec were digitized. Intensity was equalized, and F0 was manipulated by approximately 3-Hz increments (up to 12 Hz) employing the SOUNDEDITPRO16 sound editing program; all other acoustic parameters were held constant. Ten subjects each listened to 1000 pairs of these stimuli and judged whether they were the same or different. Subjects performed more accurately on modal vowel pairs than on breathy vowel pairs. Moreover, at the 3- and 6-Hz intervals, the difference between performances on modal pairs versus breathy pairs was significantly greater than the difference between modal pairs versus breathy pairs at the 9- and 12-Hz intervals. This indicates that, although frequency distinctions increase linearly in both phonation groups, a nonlinear discriminability relationship exists within each group.

Speaker-specific information in voice quality parameters

Seven instances of the vowel /a/, embedded in a carrier sentence with a variety of prosodic and segmental conditions and each produced by twenty male German speakers were measured acoustically for a variety of supralaryngeal, laryngeal, and sublaryngeal types of voice quality, as well as for fundamental frequency. Measurements included parameters that reflect the variation of the voice source in the dimension between modal and breathy phonation, as well as the influence of subglottal pressure on the voice source. The voice source parameters were corrected for supralaryngeal influence according to a procedure proposed by Kenneth N. Stevens and students, arriving at parameters such as H1 * - H2*. Post hoc comparisons between speakers revealed that the parameters that carry most speaker-specific information are F3, F0, and H1 * - H2 •. The value and limits of the results for the forensic task of speaker identification are discussed.

Pitch discrimination during breathy phonation

Just-noticeable differences (jnd’s) for frequency of complex waves with stable F0 are 0.3–0.5 Hz [Flanagan and Salow (1958)]. However, there are both articulatory and acoustic reasons to believe that jnd’s are greater during breathy phonation than during modal phonation. This study investigated pitch discrimination during breathy phonation by manipulating acoustic parameters. Both breathy vowels and modal vowels from Mazatec were digitized. Intensity was equalized, and F0 was manipulated by 0.2-Hz increments employing the OCEAN Speech Processing Program, while all other acoustic parameters were held constant. Subjects listened to pairs of these stimuli and judged whether they were the same or different. It is predicted that jnd’s would be greater during breathy phonation than during modal phonation. Results will be discussed with reference to laryngeal timing patterns in vowels in Mazatec and elsewhere. In Mazatec, tone and breathy phonation are sequenced with respect to each other on a single vowel. In languages that possess phonation contrasts without tonal contrasts [e.g., Gujarati: Fischer-Jorgensen (1971)], no sequencing is observed: breathiness pervades the vowel. It is likely that pitch discrimination plays a contributing role in such timing distinctions between Mazatec-type languages and Gujarati-type languages: Pitch is likely to be less discriminable during breathy phonation.

Function of the thyroarytenoid muscle in a canine laryngeal model.

Fundamental frequency is controlled by contraction of the thyroarytenoid (TA) and cricothyroid (CT) muscles. While activity of the CT muscle is known to tense and thin the vocal folds, little is known about the effect of the TA muscle on vocal fold vibration. An in vivo canine laryngeal model was used to examine the role of the TA muscle in controlling phonation. Isolated TA muscle activation was obtained by stimulating sectioned terminal TA branches through small thyroid cartilage windows. Subglottic pressure measures, electroglottographic and photoglottographic signals, and acoustic signals were obtained in 5 mongrel dogs during dynamic and static variations in TA muscle activity. Results indicated that TA muscle activation is a major determinant in sudden shifts from high-frequency to modal phonation. Subglottic pressure increased and open quotient decreased gradually with increasing TA activation.

Ultrasonics for ultra-clean surfaces: Industrial Finishing and Surface Coatings Vol 23 No 282 (December 1971) pp 26–28

The earliest models of phonation were based on the assumption that the glottis is closed during a part of the vibration cycle, that is, the phonation is modal. Nonmodal phonation, however, commonly occurs not only for disordered voice but also for normal voices, which often exhibit a breathy quality or irregular vibration. In this paper, we review recent work that examines acoustic data and models of nonmodal phonation in both normal and disordered voice. We first describe acoustic models that predict how the glottal source varies from modal phonation to phonation resulting from glottal configurations that are partially abducted, including a posterior glottal opening. These models are applied first to vowels of nondisordered adults, and, later in the paper, to vowels produced by adults with dysarthria. We also present results from a study in which a modified version of the two-mass model is used to resolve a seeming conflict among aerodynamic and acoustic data collected from adult female subjects with vocal-fold nodules. Some discussion of nonmodal phenomena that occur due to prosodic and emotional influences is included. Overall, it appears that current models of modal phonation can be extended to include a range of nonmodal phonation types.

Some Parameters Affecting the Differentiation of Modal-Falsetto Voice Quality

Previously [R. Colton and H. Hollien, J. Acoust. Soc. Amer. 47, 105(A), (1970)] it was reported that observers could distinguish modal and falsetto voice quality when the phonations from the two registers were presented at the same fundamental frequency and intensity. Other data [R. Colton, (unpublished)] demonstrates that modal phonations exhibit more energy in the higher harmonics than do falsetto phonations; suggesting that frequency bandwidth is an important cue for the differentiation of modal and falsetto voice quality. Phonations produced in the two vocal registers were low-pass filtered to equate the bandwidth of modal phonations to falsetto phonations. The filtered phonations were presented in a paired comparison paradigm to observers who judged the similarity or dissimilarity of voice quality of each stimulus pair. The proportion of correct responses was 0.71; a decrease of 20% when compared with the responses obtained for these phonations in an unfiltered condition. These results indicate that stimulus bandwidth is an important acoustic parameter for the differentiation of the modal and falsetto registers. However, an analysis of individual phonations suggest other acoustic differences may aid in the distinction of modal and falsetto voice quality.

Some physiologic correlates of vocal-fry phonation.

Subglottal air pressure, airflow, and electromyographic activity of four intrinsic larygeal muscles were recorded during sustained phonation in the vocal-fry and low-frequency modal registers. Nine young adult males were subjects. In modal phonation there was greater airflow, greater cricothyroid and interarytenoid muscle activity, and decreased thyroarytenoid activity than in vocal fry. No differences were found between registers for subglottal air pressure or posterior cricoarytenoid muscle activity.

Subglottal Air Pressure during Two Types of Vocal Activity: Vocal Fry and Modal Phonation

Subglottal Air Pressure during Two Types of Vocal Activity: Vocal Fry and Modal Phonation

Air flow during vocal fry phonation.

Five male and five female speakers, who were free of any voice disorder, were required to sustain vocal fry phonation at three pitch levels; one an arbitrary Standard level, another lower than the standard, and a third higher. Recordings were made and analyzed of air flow and the acoustic signal of these phonations. This study showed that: 1) the fundamentals of vocal fry were lower than those produced in the modal register; 2) air flow rates were less than found for either modal phonation or falsetto; and 3) there was no correlation between changes in fry frequency and changes in air flow.

Discussion

In the present study, we examined the relationship between various open quotients (Oqs) and phonation types, fundamental frequency (F0), and intensity by multivariate linear regression analysis (MVA) to determine which Oq best reflects vocal fold vibratory characteristics.Using high-speed digital imaging (HSDI), a sustained vowel /e/ at different phonation types, F0s, and intensities was recorded from six vocally healthy male volunteers: the types of phonation included modal, falsetto, modal breathy, and modal pressed phonations; and each phonation was performed at different F0s and intensities. Electroglottography (EGG) and sound signals were simultaneously recorded with HSDI. From the obtained data, 10 conventional Oqs (four Oqs from the glottal area function, four kymographic Oqs, and two EGG-derived Oqs) and two newly introduced Oqs (Oqedge¯+andOqedge¯) were evaluated. And, relationships between various Oqs and phonation types, F0, and intensity were evaluated by MVA.Among the various Oqs, Oqedge¯+andOqedge¯ revealed the strongest correlations with an acoustic property and could best describe changes in phonation types: Oqedge¯+ was found to be better than Oqedge¯. OqMLK, the average of five Oqs from five-line multiline kymography was a very good alternative to Oqedge¯. EGG-derived Oqs were able to differentiate between modal phonation and falsetto phonation, but it was necessary to consider the change of F0 simultaneously. MVA showed the changes in Oq values between modal and other phonation types, the degree of involvement of intensity, and no relationship between F0 and Oqs.Among Oqs evaluated in this study, Oqedge¯+andOqedge¯ were considered to best reflect the vocal fold vibratory characteristics.