Vocal Samples Research Articles

Comportamento vocal de teleoperadores pré e pós-jornada de trabalho

To evaluate the vocal behavior of receptive telemarketing operators in pre- and post-work shift moments, and to relate the results to the variable gender. Participants were 55 telemarketing operators (11 men and 44 women) working in a receptive mode in the city of Maceió (Alagoas, Brazil). A questionnaire was applied before the work shift to initially identify the vocal complaints. After that, vocal samples were recorded, comprising sustained emissions and connected speech produced 10 minutes before and 10 minutes after the workday to be later evaluated. Auditory-perceptual and acoustic analyses of voice were conducted. Vocal complaints and symptoms reported by the operators after the work shift were: dry throat (64%); neck and cervix pain (33%); hoarseness (31%); voice failure (26%); and vocal fatigue (22%).Telemarketing operators presented reduced maximum phonation time before and after the day of work (p=0.645). Data from the auditory-perceptual assessment of voice were similar in pre- and post-shift moments (p=0.645). No difference was found between moments also on acoustic analysis data (p=0.738). Telemarketing operators have high indexes of vocal symptoms after the work shift, and there are no differences between pre- and post-work shift in auditory-perceptual and acoustic assessments of voice.

Out of the mouths of babes: vocal production in infant siblings of children with ASD.

Younger siblings of children with autism spectrum disorders (ASD) are at higher risk for acquiring these disorders than the general population. Language development is usually delayed in children with ASD. The present study examines the development of pre-speech vocal behavior in infants at risk for ASD due to the presence of an older sibling with the disorder. Infants at high risk (HR) for ASD and those at low risk, without a diagnosed sibling (LR), were seen at 6, 9, and 12 months as part of a larger prospective study of risk for ASD in infant siblings. Standard clinical assessments were administered, and vocalization samples were collected during play with mother and a standard set of toys. Infant vocal behavior was recorded and analyzed for consonant inventory, presence of canonical syllables, and of non-speech vocalizations, in a cross-sectional design. Children were seen again at 24 months for provisional diagnosis. Differences were seen between risk groups for certain vocal behaviors. Differences in vocal production in the first year of life were associated with outcomes in terms of autistic symptomotology in the second year. Early vocal behavior is a sensitive indicator of heightened risk for autistic symptoms in infants with a family history of ASD.

Auditory–visual intermodal matching based on individual recognition in a chimpanzee (Pan troglodytes)

The ability to recognize familiar individuals with different sensory modalities plays an important role in animals living in complex physical and social environments. Individual recognition of familiar individuals was studied in a female chimpanzee named Pan. In previous studies, Pan learned an auditory-visual intermodal matching task (AVIM) consisting of matching vocal samples with the facial pictures of corresponding vocalizers (humans and chimpanzees). The goal of this study was to test whether Pan was able to generalize her AVIM ability to new sets of voice and face stimuli, including those of three infant chimpanzees. Experiment 1 showed that Pan performed intermodal individual recognition of familiar adult chimpanzees and humans very well. However, individual recognition of infant chimpanzees was poorer relative to recognition of adults. A transfer test with new auditory samples (Experiment 2) confirmed the difficulty in recognizing infants. A remaining question was what kind of cues were crucial for the intermodal matching. We tested the effect of visual cues (Experiment 3) by introducing new photographs representing the same chimpanzees in different visual perspectives. Results showed that only the back view was difficult to recognize, suggesting that facial cues can be critical. We also tested the effect of auditory cues (Experiment 4) by shortening the length of auditory stimuli, and results showed that 200 ms vocal segments were the limit for correct recognition. Together, these data demonstrate that auditory-visual intermodal recognition in chimpanzees might be constrained by the degree of exposure to different modalities and limited to specific visual cues and thresholds of auditory cues.

Effect of species-specificity in auditory-visual intermodal matching in a chimpanzee (Pan troglodytes) and humans

The goal of this study was to compare the performance of a chimpanzee and humans on auditory-visual intermodal matching of conspecifics and non-conspecifics. The task consisted of matching vocal samples to facial images of the corresponding vocalizers. We tested the chimpanzee and human subjects with both chimpanzee and human stimuli to assess the involvement of species-specificity in the recognition process. All subjects were highly familiar with the stimuli. The chimpanzee subject, named Pan, had had extensive previous experience in auditory-visual intermodal matching tasks. We found clear evidence of a species-specific effect: the chimpanzee and human subjects both performed better at recognizing conspecifics than non-conspecifics. Our results suggest that Pan's early exposure to human caretakers did not seem to favor a perceptual advantage in better discriminating familiar humans compared to familiar conspecifics. The results also showed that Pan's recognition of non-conspecifics did not significantly improve over the course of the experiment. In contrast, human subjects learned to better discriminate non-conspecific stimuli, suggesting that the processing of recognition might differ across species. Nevertheless, this comparative study demonstrates that species-specificity significantly affects intermodal individual recognition of highly familiar individuals in both chimpanzee and human subjects.

Measurement of the Viscoelastic Properties of the Vocal Folds

Studies of the viscoelastic properties of the vocal folds are normally performed with rheometers that use parallel plates whose interplate space is usually arbitrarily assigned a fixed value. In tissues subject to variation of thickness between samples, fixed gaps could result in different compressions, compromising the comparison among them. We performed an experimental study to determine whether different compressions can lead to different results in measurements of dynamic viscosity (DV) of vocal fold samples. We measured the DV of vocal fold samples of 10 larynges of cadavers under 3 different compression levels, corresponding to 0.2, 0.5, and 10 N on an 8-mm-diameter parallel-plate rheometer. The DV directly varied with compression. We observed statistically significant differences between the results of 0.2 and 10 N (p = 0.0396) and 0.5 and 10 N (p = 0.0442). The study demonstrated that the level of compression influences the DV measure and suggests that a defined compression level should be used in rheometric studies of biological tissues.

The Dynamics Relationship of Sentence Complexity, Childhood Stuttering, and Grammatical Development

Purpose: The present study was conducted to determine if the relationship between sentence complexity and childhood stuttering is influenced by grammatical development. The study was cross-sectional in design and observed the spontaneous speech of 6 children who stutter ranging in age from 32 to 46 months. Method: The first 100 utterances from each child's sample were scored using H. Scarborough's (1990) Index of Productive Syntax (IPSyn) and were given a numeric score that was used as an indicator of grammatical development in place of the child's age. The first 100 sentences containing a noun and verb in subject-predicate relation- ship were extracted from each sample and coded for their sentence complexity using L. L. Lee's (1974) Developmental Sentence Scoring. The utterances were also measured for length in morphemes. Sample utterances were then separated into two categories: fluent and stuttered. Results: Results showed that when conducting group comparisons, the mean complexity levels of fluent and stuttered utterances were significantly different. The difference in complexity levels of the fluent and stuttered

Oral contraceptive pill containing drospirenone and the professional voice: An electrolaryngographic analysis

Few studies have been concerned with the effects of combined oral contraceptive pills (OCP) on those who use their voices as a tool of trade. A cohort study involving 20 female professional voice users was carried out assessing irregularity of vocal fold vibration, based on: 1) period-to-period frequency peaks (CFx), and 2) period-to-period amplitude peaks (CAx) in the cycle-to-cycle excitation of the vocal tract. These vocal measures and blood samples were collected at three points of the menstrual cycle, for both natural and OCP cycles. No significant differences were found in vocal parameters assessed between the natural and OCP cycles. The intake of this OCP was not found to have a systematic effect on the vocal parameters studied. Based on these results the modern OCP preparations can be considered safe medications which do not have a negative effect on voice quality in professional voice users.

Vocal cues of ovulation in human females

Recent research has documented a variety of ovulatory cues in humans, and in many nonhuman species, the vocal channel provides cues of reproductive state. We collected two sets of vocal samples from 69 normally ovulating women: one set during the follicular (high-fertility) phase of the cycle and one set during the luteal (low-fertility) phase, with ovulation confirmed by luteinizing hormone tests. In these samples we measured fundamental frequency (pitch), formant dispersion, jitter, shimmer, harmonics-to-noise ratio and speech rate. When speaking a simple introductory sentence, women's pitch increased during high- as compared with low-fertility, and this difference was the greatest for women whose voices were recorded on the two highest fertility days within the fertile window (the 2 days just before ovulation). This pattern did not occur when the same women produced vowels. The high- versus low-fertility difference in pitch was associated with the approach of ovulation and not menstrual onset, thus representing, to our knowledge, the first research to show a specific cyclic fertility cue in the human voice. We interpret this finding as evidence of a fertility-related enhancement of femininity consistent with other research documenting attractiveness-related changes associated with ovulation.

Perturbation and nonlinear dynamic analysis of acoustic phonatory signal in Parkinsonian patients receiving deep brain stimulation

Nineteen PD patients who received deep brain stimulation (DBS), 10 non-surgical (control) PD patients, and 11 non-pathologic age- and gender-matched subjects performed sustained vowel phonations. The following acoustic measures were obtained on the sustained vowel phonations: correlation dimension (D2), percent jitter, percent shimmer, SNR, F0, vF0, and vAm. The results indicated the following: The mean D2 of control PD patients was significantly higher than the mean D2 of non-pathologic subjects and patients who received deep brain stimulation. These results suggest an improvement in PD voice in treated patients. Many PD vocal samples in this study have type 2 signals containing subharmonics that may not be suitable for perturbation analysis but are suitable for nonlinear dynamic analysis, making the D2 results more reliable. These findings show that DBS may provide measurable improvement in patients with severe vocal impairment.Learning outcomes: Readers will be able to: (1) identify the advantages of nonlinear dynamic analysis as a clinical tool to evaluate the aperiodic voice commonly found in patients with Parkinson's disease, (2) describe in general the method of obtaining a correlation dimension measure from a voice sample and the significance of this measure in terms of specific voice signal properties, (3) consider the preliminary implications from nonlinear dynamic analysis of a positive DBS effect on Parkinsonian voice and the potential for further investigations using nonlinear dynamic analysis on the influence of gender, severity of disease, and combined treatments on Parkinsonian voice improvement.

Metallic Voice: Physiological and Acoustic Features

The metallic voice is usually confused with ring or nasality by singers and nontrained listeners, who are not used to perceptual vocal analysis. They believe a metallic voice results from a rise in fundamental frequency. A diagnostic error in this aspect may lead to lowering pitch, an incorrect procedure that could cause vocal overload and fatigue. The purpose of this article is to study the quality of metallic voice considering the correlation between information of the physiological and acoustic plans, based on a perceptive consensual assumption. Fiberscopic video pharyngolaryngoscopy was performed on 21 professional singers while speaking vowel [e]--in normal and metallic modes to observe muscular movements and structural changes of the velopharynx, pharynx, and larynx. Vocal samples captured simultaneously to the fiberscopic examination were acoustically analyzed. Frequency and amplitude of the first four formants (F(1), F(2), F(3), and F(4)) were extracted by means of linear predictor coefficients (LPC) spectrum and were statistically analyzed. Vocal tract adjustments such as velar lowering, pharyngeal wall narrowing, laryngeal rise, aryepiglottic, and lateral laryngeal constrictions were frequently found; there were no significant changes in frequency and amplitude of F(1) in the metallic voice; there were significant increases in amplitudes of F(2), F(3), and F(4) and in frequency for F(2); metallic voice perceived as louder was correlated to an increase in amplitude of F(3) and F(4). Physiological adjustments of velopharynx, pharynx, and larynx are combined in characterizing the metallic voice and can be acoustically related to changes in formant pattern.

Predicting phonetic transcription agreement: Insights from research in infant vocalizations

The purpose of this study is to provide new perspectives on correlates of phonetic transcription agreement. Our research focuses on phonetic transcription and coding of infant vocalizations. The findings are presumed to be broadly applicable to other difficult cases of transcription, such as found in severe disorders of speech, which similarly result in low reliability for a variety of reasons. We evaluated the predictiveness of two factors not previously documented in the literature as influencing transcription agreement: canonicity and coder confidence. Transcribers coded samples of infant vocalizations, judging both canonicity and confidence. Correlation results showed that canonicity and confidence were strongly related to agreement levels, and regression results showed that canonicity and confidence both contributed significantly to explanation of variance. Specifically, the results suggest that canonicity plays a major role in transcription agreement when utterances involve supraglottal articulation, with coder confidence offering additional power in predicting transcription agreement.

A Weighted Reliability Measure for Phonetic Transcription

The purpose of the present work is to describe and illustrate the utility of a new tool for assessment of transcription agreement. Traditional measures have not characterized overall transcription agreement with sufficient resolution, specifically because they have often treated all phonetic differences between segments in transcriptions as equivalent, thus constituting an unweighted approach to agreement assessment. The measure the authors have developed calculates a weighted transcription agreement value based on principles derived from widely accepted tenets of phonological theory. To investigate the utility of the new measure, 8 coders transcribed samples of speech and infant vocalizations. Comparing the transcriptions through a computer-based implementation of the new weighted and the traditional unweighted measures, they investigated the scaling properties of both. The results illustrate better scaling with the weighted measure, in particular because the weighted measure is not subject to the floor effects that occur with the traditional measure when applied to samples that are difficult to transcribe. Furthermore, the new weighted measure shows orderly relations in degree of agreement across coded samples of early canonical-stage babbling, early meaningful speech in English, and 3 adult languages. The authors conclude that the weighted measure may provide improved foundations for research on phonetic transcription and for monitoring of transcription reliability.

Características vocais do canto japonês nos gêneros enka e mudo enka

OBJETIVO: comparar do ponto de vista perceptivo-auditivo as características vocais dos gêneros do canto japonês enka e mudo enka. MÉTODOS: foram selecionadas dez gravações em CD comercialmente disponíveis de cinco cantores japoneses profissionais que caracterizam o gênero enka e cinco do estilo mudo enka. Foram elaborados um protocolo de avaliação de voz com características vocais encontradas nos dois estilos da música japonesa. A avaliação foi realizada por três fonoaudiólogas especialistas na área de voz pelo Conselho Federal de Fonoaudiologia, determinando as características vocais mais marcantes em cada gênero a partir da classificação baseada na literatura. RESULTADOS: no estilo enka, o kobushi, o vibrato e crescendos e decrescendos esteve presente em 100% das amostras vocais. Foi encontrado 80% de metal, 90% de nasalidade e alternância de registro e 70% de soprosidade. No estilo mudo enka, os crescendos e decrescendos esteve presente em 100% das amostras vocais. Foi encontrado 70% de soprosidade, 90% de vibrato, 50% de alternância de registro, 40% de metal e 20% de nasalidade e kobushi. CONCLUSÃO: Comparando-se os dois gêneros musicais, enka e mudo enka, identificou-se a presença marcante do Kobushi no gênero enka além do maior predomínio de vibrato, metal, nasalidade, alternância de registros e crescendos e decrescendos. A soprosidade foi encontrada em igual proporção em relação aos dois estilos musicais. A identificação das características vocais é útil ao fonoaudiólogo bem como ao professor de canto no atendimento de cantores durante o aprendizado do canto japonês e ou no aperfeiçoamento.

Relationships between vocal characteristics and body size and shape in human males: An evolutionary explanation for a deep male voice

A deep male voice may play a role in courtship and competitive behaviours in humans by attracting female mates and indicating body size to male competitors. The current correlational study investigated the relationship between vocal measures (fundamental and formant frequencies) and both body size and shape. Vocal samples and physical measures were obtained from 50 heterosexual male volunteers. A significant negative relationship was found between fundamental frequency and measures of body shape and weight. Further, a significant negative relationship was found between formant dispersion (the relationship between successive formant frequencies) and measures of body size as well as body shape. Findings are discussed in relation to the ‘good genes’ model of sexual selection and the size exaggeration theory of laryngeal descent.

Virtual Vocalization Stimuli for Investigating Neural Representations of Species-Specific Vocalizations

Most studies investigating neural representations of species-specific vocalizations in non-human primates and other species have involved studying neural responses to vocalization tokens. One limitation of such approaches is the difficulty in determining which acoustical features of vocalizations evoke neural responses. Traditionally used filtering techniques are often inadequate in manipulating features of complex vocalizations. Furthermore, the use of vocalization tokens cannot fully account for intrinsic stochastic variations of vocalizations that are crucial in understanding the neural codes for categorizing and discriminating vocalizations differing along multiple feature dimensions. In this work, we have taken a rigorous and novel approach to the study of species-specific vocalization processing by creating parametric "virtual vocalization" models of major call types produced by the common marmoset (Callithrix jacchus). The main findings are as follows. 1) Acoustical parameters were measured from a database of the four major call types of the common marmoset. This database was obtained from eight different individuals, and for each individual, we typically obtained hundreds of samples of each major call type. 2) These feature measurements were employed to parameterize models defining representative virtual vocalizations of each call type for each of the eight animals as well as an overall species-representative virtual vocalization averaged across individuals for each call type. 3) Using the same feature-measurement that was applied to the vocalization samples, we measured acoustical features of the virtual vocalizations, including features not explicitly modeled and found the virtual vocalizations to be statistically representative of the callers and call types. 4) The accuracy of the virtual vocalizations was further confirmed by comparing neural responses to real and synthetic virtual vocalizations recorded from awake marmoset auditory cortex. We found a strong agreement between the responses to token vocalizations and their synthetic counterparts. 5) We demonstrated how these virtual vocalization stimuli could be employed to precisely and quantitatively define the notion of vocalization "selectivity" by using stimuli with parameter values both within and outside the naturally occurring ranges. We also showed the potential of the virtual vocalization stimuli in studying issues related to vocalization categorizations by morphing between different call types and individual callers.

Good Copy, Bad Copy

Good Copy, Bad Copy

Vocal development of infants with very low birth weight

This study describes the vocal development of infants born with very low birth weights (VLBW). Samples of vocalizations were recorded from three groups of infants when they were 8, 12 and 18 months of age: preterm VLBW infants with bronchopulmonary dysplasia (BPD), preterm VLBW infants without BPD, and healthy full‐term infants. Infants with BPD produced significantly smaller canonical syllable ratios than the full‐term infants throughout the period of study. Premature VLBW infants who did not suffer from BPD produced relatively little canonical babble at 8 months of age, but were performing within the range of the full‐term infants at 18 months of age. At 18 months of age, the infants with BPD were reported to have significantly smaller expressive vocabulary sizes than the healthier preterm and full‐term infants.

Acoustic and Perceptual Appraisal of Vocal Gestures in the Female Classical Voice

Long-term average spectra (LTAS) have identified features in the sounds of singers and have compared different vocal qualities based on energy changes that occur during different vocal tasks. In this study, we compared the perceptual ratings of vocal quality of expert pedagogues with acoustic measures performed on LTAS. Fifteen expert judges rated 24 samples with six repeats of six advanced singing students under two conditions: "optimal" (O), which represented the application of the maximal open throat technique; and "suboptimal" (SO), which represented the application of the reduced open throat technique. LTAS were performed on each singing sample, and two conventional assessments of peak energy height [singing power ratio (SPR)] and peak area [energy ratio (ER)] were calculated on each LTAS. Perceptual scores, SPR, and ER were rank ordered. We then compared perceptual rankings with rankings of acoustic measures (SPR and ER) to assess whether these acoustic measurements matched the perceptual judgments of vocal quality. Although we found the expected significant relationship between SPR and ER, there was no relationship between perceptual ratings of vocal samples or singers based on SPR or ER. These findings suggest that because LTAS measures are not consistent with perceptual ratings of vocal quality, such measurements cannot define a voice of quality. Future research with LTAS to assess vocal quality should consider alternative measures that are more sensitive to subtle differences in vocal parameters.

The Singing Power Ratio as an Objective Measure of Singing Voice Quality in Untrained Talented and Nontalented Singers

A growing body of contemporary research has investigated differences between trained and untrained singing voices. However, few studies have separated untrained singers into those who do and do not express abilities related to singing talent, including accurate pitch control and production of a pleasant timbre (voice quality). This investigation studied measures of the singing power ratio (SPR), which is a quantitative measure of the resonant quality of the singing voice. SPR reflects the amplification or suppression in the vocal tract of the harmonics produced by the sound source. This measure was acquired from the voices of untrained talented and nontalented singers as a means to objectively investigate voice quality differences. Measures of SPR were acquired from vocal samples with fast Fourier transform (FFT) power spectra to analyze the amplitude level of the partials in the acoustic spectrum. Long-term average spectra (LTAS) were also analyzed. Results indicated significant differences in SPR between groups, which suggest that vocal tract resonance, and its effect on perceived vocal timbre or quality, may be an important variable related to the perception of singing talent. LTAS confirmed group differences in the tuning of vocal tract harmonics.

Common-sense beliefs, recognition and the identification of familiar and unfamiliar speakers from verbal and non-linguistic vocalizations

Listeners first listened to tape-recorded speech samples of words and non-linguistic vocalizations to decide whether each came from a familiar or an unfamiliar speaker. If a vocalization was judged as being uttered by a familiar speaker, listeners were asked to identify, if possible, the individual by name. Listeners were instructed not to guess. Confidence-accuracy scores in judgements and identification also were assessed. A separate group of participants attempted to predict the accuracy of performance of the listeners for each of the utterances made by the familiar and unfamiliar speakers. Tokens of some utterances, namely the words hello and help me and the sounds of laughter and clearing the throat, allowed equally good performance on the familiar/unfamiliar decision whether their source was a familiar or an unfamiliar speaker. For other vocalizations (moan, cough, grunt and sigh) listeners were better at detecting unfamiliar speakers than at recognizing familiar speakers. Those utterances judged to be made by familiar speakers led to correct identifications approximately 50 percent of the time on hearing the words hello and help me, and laughter. All other utterances led to less than 30 percent correct speaker identifications. For those unfamiliar speakers who were falsely recognized as familiar, listeners falsely identified by name between 22 and 30 percent of the vocalizations. Few of the confidence-accuracy relationships were significant. Laypersons’ common-sense beliefs for speaker identification were generally unrealistic.