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The speed with which the vocal folds adduct to the midline is considered an important variable in the etiology of some voice disorders and may also be a meaningful indicator of central or peripheral neural dysfunction. It is proposed that the time lag between the rise of the sound pressure (SP) and electroglottographic (EGG) signals, measured at the onset of phonation, provides a useful index of vocal attack time. This report describes the experimental validation of this measure, whereby the SP and EGG signals were recorded synchronously with high-speed videoendoscopy, from which a digital kymogram was generated. It is shown that, after appropriate signal processing, the intersignal time delay provides a potentially useful measure that varies with vocal attack characteristics. The proposed method calls for no invasive procedures and relies on signals that are routinely obtained in most clinical settings. Unlike acoustic "rise time" measures of voice onset, the glottographic measure involves no operator intervention, requires no arbitrary decisions about measurement points, and may be accomplished quickly and automatically on any personal computer.

SUMMARY Respiratory activity during crying was investigated in seven infants (age-range 28 to 55 weeks) who were each observed three times at intervals averaging four weeks. Pneumographic measurement of thoracic and abdominal circumference changes was used to obtain information concerning respiratory rate, inspiratory/expiratory time relationships, and regional predominance and co-ordination. Respiration during crying was characterised by a marked reduction in respiratory rate over the age range, stability of the I-fraction, and equal thoracic and abdominal participation with some asynchronism. When taken with the results of other studies, the present findings suggest that the respiratory adaptations seen in crying are not unlike those observed in adult speech, and that there are important developmental changes in the respiratory adaptations of the cry of the infant. RESUME Developpement desfacteurs de temps respiratoire dans le cri de l'enfant L'activite respiratoire durant le cri a eteetudiee chez sept nourrissons (de 28 a 55 semaines) qui ont ete observes chacun trois fois a des intervalles moyens de quatre semaines. Des mesures pneumographiques des modifications de circonference thoracique et abdominale ont ete utilisees pour obtenir des informations concernant la frequence respiratoire, le rapport temps inspiratoire sur temps expiratoire, la predominance regionale et la coordination. La respiration durant le cri est caracterisee par une reduction marquee de la frequence respiratoire a tout âge, la stabilite de la fraction inspiratoire et la participation egale thoracique et abdominale avec quelque asynchronisme. Quand elles sont comparees a d'autres etudes, les presences donnees suggerent que les adaptations respiratoires observees dans le cri ne different pas de celles observees dans le langage adulte et qu'il existe des modifications developmentales importantes dans les adaptations respiratoires du cri du nourrisson. ZUSAMMENFASSUNG Entwicklung von Atmungsgrosen beim kindlichen Schrei Die Atemaktivitat wahrend des Schreiens wurde bei sieben Kindern (zwischen 28 und 55 Wochen) untersucht, die je dreimal im Abstand von durchschnittlich vier Wochen beobachtet wurden. Atemabhangige Umfangsanderungen des Thorax und Abdomens wurden als Parameter fur Atemfrequenz, Zeitverhaltnis von In- und Exspiration und regionales Uberwiegen und Koordination gewertet. Die Atmung wahrend des Schreiens war charakterisiert durch eine deutliche Abnahme der Atemfrequenz in jedem Alter, Stabilitat der I-Fraktion und gleicher thorakaler und abdomineller Beteiligung mit nur geringgradig gestorter Koordination. Vergleicht man die Ergebnisse dieser Arbeit mit anderen Unter-suchungen so stellt sich heraus, das die Atemanpassungen beim Schreien in sehr ahnlicher Weise bei der Erwachsenensprache beobachtet wurden und das es wichtige entwicklungs-bedingte Veranderungen in der Atemanpassung beim kindlichen Schrei gibt. RESUMEN Desarrollo de los faetores de tiempo respiratorio en el llanto del lactante Se investigo la actividad respiratoria durante el llanto en siete ninos (de edad entre 28 y 55 semanas) cada uno de los cuales fue observado tres veces con intervalos promedios de cuatro semanas. Se utilizo la medicion pneumografica de los cambios de perimetro toracico y abdominal para obtener information respecto a la frecuencia respiratoria, relation de tiempo inspiracion-espiracion, predominio regional y coordination. La respiration durante el llanto estaba caracterizada por una marcada reduction en el ritmo respiratorio por encima del margen de edad, estabilidad de la fraccion I y participacion igual toracica y abdominal con algun asincronismo. Los presentes hallazgos, al ser comparados sus resultados con los de otros estudios, sugieren que las adaptaciones respiratorias vistas en el llanto no son desemejantes de aquellas observadas en el lenguaje del adulto. y que existen importantes cambios de desarrollo en las adaptaciones respiratorias del llanto del lactante.

Toward a consensus on symbolic notation of harmonics, resonances, and formants in vocalization

(2000). Commentaries: Intuition and Evidence: A Reaction to Watson and Clark. Advances in Speech Language Pathology: Vol. 2, No. 1, pp. 43-47.

Although recent years have seen an explosive growth in the available number of tests and measurements of vocal function, it is not clear that vocal diagnosis and evaluation have become correspondingly more precise nor therapy more efficacious. In short, there is little basis for believing that more extensive testing has refined clinical practice. Some reasons for this situation are addressed, and it is suggested that attention to a few basic and common-sense principles can improve the utility and efficiency of evaluation of vocal dysfunction.

The purpose of the present study was to further clarify a definition of belting in physiological and acoustic terms. Twenty professional female singers produced triads ascending by halftone steps from C₄ to C₅ and sang the last four measures of a popular Broadway ballad in both legit and belt styles. Vocal source differences between belt and legit singing modes were assessed with respect to closed quotient (CQ) and speed quotient (SQ) computed from the electroglottographic waveform during productions of /ma/ triads covering approximately one octave. Differences in supraglottal configuration were evaluated in terms of the ratio (dB) of the amplitudes of the first and second harmonics of /I/ sustained at the pitch A₅(b), as noted in the long-term average spectrum. CQ did not vary significantly as a function of the singing type. SQ, however, decreased monotonically in association with increasing pitch level in both legit and belt singing styles. Belt mode phonations had higher SQ's than those of legit mode phonations at the same pitch. A repeated-measures analysis of variance demonstrated that the data differences associated with both pitch level and with singing mode were significant beyond P0.01. Analysis of the relative magnitude of the first and second harmonics showed that the direction of the harmonic ratio varied between styles. In legit singing style, H₁ was always stronger than H₂, but this unidirectionality of amplitude was not characteristic of belt singing, for which the second harmonic had greater amplitude in 25% of the cases. Implications of these results are discussed with regard to a new definition of belting.

The objectives of this study were to determine appropriate acoustic and outcome measures for the evaluation of a method of laryngeal manual therapy (LMT) used in the treatment of patients with muscle tension dysphonia (MTD). The effects of this technique were also investigated. The study was based on the hypotheses that the vertical position of the larynx in the vocal tract would lower, that the quality of the voice would normalize, and that a reduction in any vocal tract discomfort (VTD) would occur after LMT. This was a small, prospective, repeated measures pilot study in which each member of the research team was "blinded" to all other stages of the study and during which all data were anonymized until the final stage of data analysis. Ten subjects presenting with MTD completed outcome measures and provided audiorecordings immediately before, immediately after, and 1 week after LMT. The Kay CSL 4150 was used for signal acquisition and for some acoustic measurements. Spectrographic evaluation was accomplished with Praat. A new perceptual, self-rating scale, the VTD scale, and a new proforma for use by the clinician for palpatory evaluation, were developed for the study. Relative average perturbation during connected speech was significantly reduced after LMT, indicating a reduction in abnormal vocal function. The severity and frequency of VTD was shown to have reduced after LMT. This pilot study showed positive evidence for LMT as a method of therapy in the treatment of hyperfunctional voice disorders. Its effects were shown to be measurable with both acoustical analysis and the VTD scale.

This paper considers the effects of nonstationarity, noise, and finite data sets on the estimation of the correlation dimension of time-series data characterizing the vibratory behavior of the vocal folds. The electroglottographic signal of sustained /a/ phonations from 10 healthy subjects and 20 subjects with vocal fold pathologies were used to reconstruct the state space in successively higher embeddings using the method of lags. The dimension values were calculated from the scaling region (the level area of the slope plots) which did not increase for higher embeddings. Reasonably defined scaling regions were found in all of the data from the healthy subjects and from five of the pathologic subjects, with values saturating between the first and second embeddings. The EGG data from those five pathologic subjects were nearly periodic. From the remaining 15 subjects, the scaling regions were highly constricted with nonconstant slopes, so that dimension values could not be confidently estimated. The results suggest that the correlation dimension is a highly subjective measure which is not usefully applied to abnormal EGG data. It is recommended that, if used, correlation dimension statistics need to be presented cautiously, and graphical presentation of the data should be included.

Voice produced on inhaled air is a form of phonation that has received relatively little attention despite its apparent usefulness in the assessment of vocal function. This preliminary investigation was designed to describe the general characteristics of vocalization driven by an ingressive phonatory airflow. Vocal fundamental frequency (F0), electroglottographic (EGG), and airflow measures were examined in 16 normal men and women, who alternated between inspiratory and expiratory voice. Mean F0 routinely increased during inspiratory voice segments, shifting on average 5.1 semitones above the subjects' comfortable expiratory voice frequency. EGG data showed inspiratory voice to be associated with a more symmetrical pattern of vocal fold contact characterized by a prolonged interval of increasing contact. Both short-term F0 variability (jitter) and EGG amplitude perturbation were significantly higher during inspiratory voice. Stroboscopic examination of four of the subjects showed caudal displacement of the larynx and lengthened vocal folds associated with inspiratory phonation. The absolute airflow rate was significantly greater for inspiratory phonation, on average 48.5% higher than during normal expiratory voice. It was also found that both inspiratory pulse and falsetto vibratory patterns could be produced by at least some of the subjects, indicating some control over the mode and frequency of vocal fold vibration when driven by an ingressive airflow.

The timing of prephonatory movements of the larynx, rib cage, and abdomen was examined in order to gain insight into the contribution of the vocal folds to the posturing of the chest wall. A simple stimulus-response paradigm was used in eliciting brief utterances—/α/ and /hα/—from six adult males. Chest wall movements were observed using mercury strain gages while simultaneous electroglottographic and airflow records provided information about vocal fold behavior. Independence of prephonatory laryngeal and chest wall behavior was demonstrated. Laryngeal adjustment preceded the start of vocal fold oscillation by a constant amount of time, whereas the time of onset of the chest wall adjustment varied as a function of the utterance type. The qualitative characteristics of prephonatory chest wall posturing were unaffected by altering glottal configuration requirements. Rib cage enlargement occurred during postural adjustment while the vocal folds were abducted (in preparation for/h/). This implies that rib cage enlargement during prephonatory chest wall posturing was not a passive response to abdominal compression.

Respiratory activity during crying was measured in a semilongitudianl study of 10 normal infants aged two days to eight months. Temporal aspects of respiration during crying showed marked change with age: athe duration of the expiratory phase steadily increased, while the duration of the inspiratory phase remained remarkable constant, producing an ever-lower I-fraction. A previous study reported no developmental changes in the temporal aspects of the acoustic cry signal from one to seven months of age. Reasons for the divergent findings of the present study arepresented, and it is suggested that respiratory behavior may be a better indicator of developmental changes in the crying act thanthe acoustic signal.

Examination of some acoustic characteristics of sustained pulse register phonation in normal adults confirmed the existence of two distinct waveform patterns. Trains of similar, highly damped waves with relatively uniform spacing predominated, but the “dicrotic” pattern previously described accounted for about 15% of the total sample. Average differences in the periods of continguous cycles (jitter) were extremely large—on the order of 20% of the fundamental period. Jitter did not vary with fundamental frequency according to the pattern documented in modal register and, thus, jitter ratio is not a useful normalizing descriptor of pulse register pertubation.

This study reports airflow-intensity relationships observed in crescendo and decrescendo phonations produced at three fundamental frequency levels by l0 men. The purpose of the investigation was to study the possible influence of lung volume on airflow-intensity relationships. Of the 30 decrescendo phonations, 26 showed statistically significant correlation coefficients and none showed significant negative correlations. The crescendo phonations, however, showed greater inter- and intrasubject variability. Of the 30 crescendo phonations, 16 showed statistically significant positive correlation coefficients and 6 showed significant negative correlations. Because lung inflation varied directly with intensity in the decrescendo task and indirectly in the crescendo task, it was concluded that lung volume does influence the consistency and strength of relationship between airflow and intensity. The findings are discussed in terms of the influence of lung volume on the relative contributions of glottal resistance and expiratory force to the regulation of subglottal pressure.

A technique for estimating lung volume change is described. Voltages proportional to rib cage and abdominal hemicircumferences are produced by Whitney-gage transducers in a standard bridge circuit. The weighted sum of these voltages can be adjusted to produce a good estimate of lung volume change. The instrumentation does not obstruct articulatory movements, load the chest wall, or require restraint of the subject. In addition, it is easy and inexpensive to construct.

The literature has noted that speakers often perceive their own speaking pitch levels differently than listeners perceive them. However, little information is available regarding the specific characteristics of such perceptual differences. Speaking pitch level self-perception was explored in a group of 11 young adult males who served both as talkers and listeners. As a talker, each subject judged his own speaking pitch level in the process of speaking (live judgments) and during taped replay (taped judgments). The subjects' self-rankings in these two tasks and the rank order of taped voices as judged by listeners were compared to fundamental frequency rankings for the voices. The results indicated that the subjects judged their own taped voices in the same way that the listeners judged them, and the judgments corresponded to fundamental frequency rankings. During the live judgments, the subjects avoided extreme self-rankings, preferring to rank themselves closer to an average pitch level. The findings may have clinical significance in the remediation of certain voice disorders.

Signal-averaging and autocorrelation analysis revealed that the cardiovascular system exerts a modest but consistent influence on vocal fundamental frequency (F 0 ), accounting for approximately 0.5% to 20% of the absolute F 0 perturbation (jitter) measured during a sustained phonation. There was also a marked trend for this percentage to decrease with increasing vocal F 0 . Estimated mean "deterministic jitter" (J ) values of 3.7 µsec (SD = 3.2) and 0.9 µsec (SD = 0.5) were derived from 6 normal male and 6 normal female subjects, respectively, with an overall mean of 2.3 µsec (SD =2.7). These values represent approximately 6.9% of the mean total jitter for men and 2.4% of the mean total jitter for women, or about 4.6% for all subjects. The results are discussed in terms of their significance regarding more reliable vocal jitter measurement.

In an effort to determine the possible distribution of neuromuscular spindles in the human larynx, a histologic examination of the adductors and tensors of the vocal folds was undertaken. The muscl...

The possibility that prephonatory chest wall posturing is abnormal in stutterers was explored by observing rib cage and abdominal hemicircumference changes during the interval between the presentation of a stimulus and the production of/alpha/by a group of stutterers (N = 5). It was found that the patterns of chest wall adjustment for phonation were qualitatively identical in the stutterers and in a comparable group of normal men studied previously. There was, however, a significant difference in the way in which lung volume changed during the execution of the chest wall adjustment. This was considered to be indicative of delayed glottal closure among the stutterers rather than representative of a primary ventilatory disturbance.

Signal‐averaging techniques reveal that the vocal fundamental frequency (F0) of a sustained vowel is modulated over a period equal to that of the speaker’s heart cycle. Average F0 deviation varies in an orderly way from about 0.5% to about 1.0% as F0 changes. Location of the peak deviation in the time frame of the heart cycle also changes systematically with vocal F0. Modulation of the vocal F0 is likely to be caused by pressure‐related changes in the stiffness of the vascular bed of the vocal folds and by alterations of the geometry of the thyroarytenoid muscle produced by periodic vascular engorgement.

Movements of the chest wall during the interval between an acoustic stimulus and the subject’s vocal response were examined and timed in eight normal males. The reaction-time interval was divisible into two phases, a latency period with duration independent on chest wall status at the time of stimulus and an adjustment period during which the rib cage and abdomen usually moved oppositionally to achieve a prephonatory postural set. The time required for this adjustment varied significantly with lung volume, but was independent of the ventilatory phase previously in progress.

In addition to cycle-by-cycle (jitter) and long-term (intonation contour and declination) changes, vocal fundamental frequency (Fo) is known to vary during moments of production of individual phones. This study explored the relationship between intra-oral pressure and Fo during the production of the English voiced fricatives (v), (z), (o), and (3). Target words were embedded in a carrier phrase spoken with three different patterns of sentence stress. Fo changed at a mean rate of -3.59 Hz/cmH2O and -7.96 Hz/cmH2O in men and women, respectively. No significant difference was observed among the different fricatives nor among the several stress patterns. A significant sex effect, not observed in a prior related study, was eliminated by conversion of the Fo data to semitones. The observed magnitudes of the ratios of Fo change to pressure change are consistent with several earlier studies that explored the effect of passive transglottal pressure changes on Fo. The present findings imply that, although Fo regulation is involved in the generation of different intonation contours, the laryngeal system is not compensated to maintain Fo in the face of the transitory changes in vocal-tract aerodynamics that accompany voiced fricative production.