O espectro médio de longo termo na pesquisa e na clínica fonoaudiológica

Long-Term Average Spectrum as an Outcome Measure of Vocal Projection After Resonant Voice Therapy in Carnatic Classical Singers

BACKGROUND

The current study evaluated the effects of resonant voice therapy (RVT) on the long-term average spectrum (LTAS) parameters of vocally healthy trained Carnatic classical singers. The objectives of the study were i) to understand the perceptual differences and ii) to understand the change in LTAS contour parameters and the alpha ratio of the sung voice samples of the trained Carnatic classical singers before and after RVT.

METHOD

The study used a quasi-experimental, pre post design and purposive-convenient sampling method. Nineteen vocally healthy singers (4 males and 15 females) aged 18-25 years (M = 23; standard deviation [SD] = 2.09) with minimum 10 years of formal Carnatic classical vocal music training volunteered to participate in the study. The audio recordings of the participants' sung aakaara (/a/ vowel singing) were obtained before and after the training. All participants were assigned to a 21-day-long RVT training program scheduled as 15-20 minutes sessions. The participants' pre-training and post-training singing samples were subjected to LTAS analysis. The spectral mean, SD, skewness, kurtosis, and alpha ratio were extracted from the sung samples. The mean and SD of the parameters were obtained using descriptive statistical methods. Wilcoxon signed-rank test was performed to evaluate significant differences in the obtained parameters across pre-training and post-training sung samples.

RESULTS

Though there was an increase in perceptual vocal resonance in the post-training sung samples, the difference was observed to be statistically insignificant. The results indicated a significant difference only in the alpha ratio values, which were decreased, indicating an increase in the high-frequency energies. The descriptive statistical evaluations showed a reduction in the parameters of spectral mean, SD, skewness, and kurtosis.

CONCLUSION

The observations from the current study indicated that the RVT training increased the energies of higher frequencies in the singers' voices (1-5 kHz). This high-frequency energy favored improved voice projection, imparting perceptual resonance or ringing quality of the voice.

The Performance of the Acoustic Voice Quality Index and Acoustic Breathiness Index in Synthesized Voices

OBJECTIVE

The aim of the present study was to investigate the performance of the Acoustic Voice Quality Index (AVQI) and the Acoustic Breathiness Index (ABI) in synthesized voice samples.

METHOD

The validity of the AVQI and ABI performances was analyzed in synthesized voice samples controlling the degree of predefined deviations for overall voice quality (G-scale) and breathiness (B-scale). A range of 26 synthesized voice samples with various severity degrees in G-scale with and without prominence of breathiness for male and female voices were created.

RESULTS

ABI received higher validity in the evaluation of breathiness than AVQI. Furthermore, ABI evaluated accurately breathiness degrees without considering roughness effects in voice samples and confirmed the findings of other studies with natural voices. Furthermore, ABI was more robust than AVQI in the evaluation of severe voice-disordered voice samples. Finally, AVQI represented moreover overall voice quality with an emphasis of breathiness evaluation and less roughness although roughness had a necessary component in overall voice quality evaluation.

CONCLUSION

AVQI and ABI are two robust measurements in the evaluation of voice quality. However, ABI received fewer errors than AVQI in the analyses of higher abnormalities in the voice signal. Disturbances of other subtypes of abnormal overall voice quality such as roughness were not demonstrated in the results of ABI.

Bright Voice Quality and Fundamental Frequency Variation in Non-binary Speakers

OBJECTIVES

1) To investigate if vocal variation produced by assigned-female-at-birth (AFAB) non-binary people differed from vocal variation produced by cisgender (cis) participants. Cue values produced by non-binary participants were predicted to differ from those values produced by cisgender participants. 2) To determine if previous subjective assessments of bright voice quality in AFAB non-binary participants were quantifiable, and if so, if non-binary and cisgender participants differed in their voice quality production.

STUDY DESIGN

A quantitative comparative research design.

METHODS

Phonetic and statistical analyses of continuous speech samples produced by AFAB non-binary and cisgender participants. Vocal cues were mean fundamental frequency (F0) and bright voice quality, measured by cepstral peak prominence-smoothed and spectral slope, with speaker gender as the predictor.

RESULTS

At the group level, non-binary participants produced intermediate F0 values - significantly lower than the cis women's and significantly higher than the cis men's. Individually, the majority of non-binary participants produced mean F0 in this intermediate range. Non-binary participants produced significantly less negative spectral slope and higher cepstral peak prominence-smoothed, indicative of a brighter, more resonant voice quality. Individual-level results indicated that vocal training and vocal tract physiology did not fully account for the results found.

CONCLUSION

Participants' agency, particularly their motivation to alter vocal output to avoid being misgendered, has an effect on the AFAB non-binary participants' F0 production and potentially their voice quality. The majority of AFAB non-binary participants uniquely produced the cue combination of intermediate F0 and bright voice quality.

Behavioral and Neural Variability of Naturalistic Arm Movements

Motor behaviors are central to many functions and dysfunctions of the brain, and understanding their neural basis has consequently been a major focus in neuroscience. However, most studies of motor behaviors have been restricted to artificial, repetitive paradigms, far removed from natural movements performed "in the wild." Here, we leveraged recent advances in machine learning and computer vision to analyze intracranial recordings from 12 human subjects during thousands of spontaneous, unstructured arm reach movements, observed over several days for each subject. These naturalistic movements elicited cortical spectral power patterns consistent with findings from controlled paradigms, but with considerable neural variability across subjects and events. We modeled interevent variability using 10 behavioral and environmental features; the most important features explaining this variability were reach angle and day of recording. Our work is among the first studies connecting behavioral and neural variability across cortex in humans during unstructured movements and contributes to our understanding of long-term naturalistic behavior.

Relationship of Cepstral Peak Prominence-Smoothed and Long-Term Average Spectrum with Auditory–Perceptual Analysis

Cepstral peak prominence-smoothed (CPPs) and long-term average spectrum (LTAS) are robust measures that represent the glottal source and source-filter interactions, respectively. Until now, little has been known about how physiological events impact auditory–perceptual characteristics in the objective measures of CPPs and LTAS (alpha ratio; L1–L0). Thus, this paper aims to analyze the relationship between such acoustic measures and auditory–perceptual analysis and then determine which acoustic measure best represents voice quality. We analyzed 53 voice samples of vocally healthy participants (vocally healthy group-VHG) and 49 voice samples of participants with behavioral dysphonia (dysphonic group-DG). Each voice sample was composed of sustained vowel /a/ and connected speech. CPPs seem to be the best predictor of voice deviation in both studied populations because there was moderate to strong negative correlations with general degree, breathiness, roughness, and strain (auditory–perceptual parameters). Regarding L1–L0, this measure is related to breathiness (moderate negative correlations). Hence, L1–L0 provides information about air leak through closed glottis, assisting the phonatory efficiency analysis.

Long-term Average Speech Spectra of Postlingual Cochlear Implant Users

Long term average speech spectra (LTASS) is a commonly used voice analysis method for different purposes. This method offers an acoustic representation of the language in daily conservations. Results of that method can be altered by the deteriorations in the auditory feedback loop. Hearing losses occurred in the post lingual stage of life have some serious negative effects on the auditory feedback loop. Cochlear implantation may help these patients with regards to auditory feedback loop. Therefore, we aimed to evaluate the LTASS of cochlear implant users whose have a post lingual hearing loss. We assessed the LTASS of 24 cochlear implant users and compared our findings with normal hearing subjects. Our findings revealed that cochlear implant users have similar LTASS findings with normal hearing subjects. We conclude that cochlear implantation helps to the recovery of auditory feedback loop in patients with post lingual hearing losses.

Long term average speech spectra of Turkish

Long-term average speech spectra (LTASS) are a voice analysis method that is recommended to be used in various areas, such as hearing aid fittings, automatic speaker recognition and voice disorders. Evaluations of LTASS in different languages have been published; however, this analysis has not been conducted for the Turkish. Therefore, the first aim of this study was to conduct this analysis, generate normative values and compare the obtained LTASS curve for the Turkish with those obtained for other languages reported in the literature. To achieve this objective, 40 adults with healthy hearing and speech characteristics were evaluated. Long-term spectral shape is presented in a graphical form, with visual comparisons to other research findings. Spectral differences by gender were analyzed, with statistically significant differences observed between gender groups and overall LTASS. The LTASS curve for the Turkish is similar to those reported for other languages, but there are also observable differences. Use of generated speech signals in hearing aid fitting procedures is recommended.

Auditory-Perceptual Evaluation of Voice Quality of Cochlear-implanted and Normal-hearing Individuals: A Reliability Study

OBJECTIVE

This study aimed to present an experience in rating voices of adults with normal hearing and adults with cochlear implants and critically examine the outcomes, discussing pros and cons of the methodology used.

STUDY DESIGN

This is a cross-sectional, prospective study.

METHODS

One hundred and fifty voice samples, consisting of 50 sustained vowels, 50 samples of connected speech, and 50 samples of conversational speech, belonging to 25 adults with hearing impairment with cochlear implants and 25 adults with normal hearing, were perceptually analyzed for inter-rater agreement and intra-rater reliability. Three experienced judges rated the voice samples using visual analog scales of parameters considered relevant for cochlear-implanted population such as articulation, intonation, and resonance. The raters participated in three training sessions for calibration and had 1 month to complete the ratings individually. Twenty percent of the samples were repeated randomly to verify intra-rater reliability. The levels of agreement and reliability were verified using the interclass correlation coefficient.

RESULTS

The inter-rater agreement varied widely across the parameters and speech tasks, from poor to excellent agreement. The only parameter for which the raters maintained consistently good or excellent agreement for all groups and emissions was the pitch. For intra-rater reliability, two of the raters presented excellent reliability for most parameters across all of the speech tasks, whereas one rater presented more inconsistencies.

CONCLUSIONS

In this reliability study, factors such as extensive deadline for the auditory perceptual evaluation, lack of periodic recalibration, speech tasks, and familiarity with the population studied were identified as factors that contributed to inconsistent reliability results.

Acoustic markers to differentiate gender in prepubescent children's speaking and singing voice

OBJECTIVES

Investigation sought to determine whether there is any acoustic variable to objectively differentiate gender in children with normal voices.

METHODS

A total of 30 children, 15 boys and 15 girls, with perceptually normal voices were examined. They were between 7 and 10 years old (mean: 8.1, SD: 0.7 years). Subjects were required to perform the following phonatory tasks: (1) to phonate sustained vowels [a:], [i:], [u:], (2) to read a phonetically balanced text, and (3) to sing a song. Acoustic analysis included long-term average spectrum (LTAS), fundamental frequency (F0), speaking fundamental frequency (SFF), equivalent continuous sound level (Leq), linear predictive code (LPC) to obtain formant frequencies, perturbation measures, harmonic to noise ratio (HNR), and Cepstral peak prominence (CPP). Auditory perceptual analysis was performed by four blinded judges to determine gender.

RESULTS

No significant gender-related differences were found for most acoustic variables. Perceptual assessment showed good intra and inter rater reliability for gender. Cepstrum for [a:], alpha ratio in text, shimmer for [i:], F3 in [a:], and F3 in [i:], were the parameters that composed the multivariate logistic regression model to best differentiate male and female children's voices.

CONCLUSION

Since perceptual assessment reliably detected gender, it is likely that other acoustic markers (not evaluated in the present study) are able to make clearer gender differences. For example, gender-specific patterns of intonation may be a more accurate feature for differentiating gender in children's voices.

Differences in acoustic and perceptual parameters of the voice between elderly and young women at habitual and high intensity

INTRODUCTION AND OBJECTIVES

The present study aimed to compare elderly and young female voices in habitual and high intensity. The effect of increased intensity on the acoustic and perceptual parameters was assessed.

METHODS

Sound pressure level, fundamental frequency, jitter, shimmer, and harmonic to noise ratio were obtained at habitual and high intensity voice in a group of 30 elderly women and 30 young women. Perceptual assessment was also performed.

RESULTS

Both groups demonstrated an increase in sound pressure level and fundamental frequency from habitual voice to high intensity voice. No differences were found between groups in any acoustic variables on samples recorded with habitual intensity level. No significant differences between groups were found in habitual intensity level for pitch, hoarseness, roughness, and breathiness. Asthenia and instability obtained significant higher values in elderly than young participants, whereas, the elderly demonstrated lower values for perceived tension and loudness than young subjects.

CONCLUSIONS

Acoustic and perceptual measures do not demonstrate evident differences between elderly and young speakers in habitual intensity level. The parameters analyzed may lack the sensitivity necessary to detect differences in subjects with normal voices. Phonation with high intensity highlights differences between groups, especially in perceptual parameters. Therefore, high intensity should be included to compare elderly and young voice.

Influência de alterações posturais, acompanhadas por fotogrametria computadorizada, na produção da voz

INTRODUÇÃO: Há considerável evidência da importância de uma postura adequada para um bom desempenho vocal. As alterações posturais podem influenciar diretamente a projeção da voz. OBJETIVO: Identificar a influência das diferentes posturas corporais na produção da voz. MATERIAIS E MÉTODOS: Foram realizadas as análises de 25 amostras vocais de um indivíduo que emitiu a vogal sustentada /a/ em três diferentes posturas corporais: a) ortostática natural; b) anteriorização da cabeça associada com extensão da coluna cervical; c) aumento da cifose torácica associada com anteriorização de cabeça. O indivíduo foi fotografado simultaneamente ao processo de gravação da voz. Para certificar-se de que o indivíduo estava sempre na mesma posição, as posturas foram acompanhadas por fotogrametria computadorizada pelo programa Corel Draw 10®. RESULTADOS: Os resultados da fotogrametria foram analisados pelo teste de Levene que não mostrou diferenças significativas em oito dos nove ângulos estudados. A voz foi avaliada por análise acústica e avaliação subjetiva perceptivo-auditiva. A acústica foi analisada pelos testes Anova e Tukey, que mostraram diferença na variável jitter - relacionada à qualidade vocal - entre as posturas A e B. A comparação das posturas A e B e A e C pela análise perceptivo-auditiva da voz mostrou mudanças no tom, piora na qualidade e na ressonância vocal. CONSIDERAÇÕES FINAIS: As mudanças encontradas na voz provam que a melhor produção do som é na postura ereta. O fisioterapeuta é o profissional indicado para a orientação postural e correção das más posturas.

Características da espectrografia de banda larga e estreita da emissão vocal de homens com laringe sem afecções

OBJETIVO: caracterizar as espectrografias vocais de um grupo de homens adultos jovens. MÉTODO : 25 homens adultos jovens, sem queixas vocais, com diagnóstico otorrinolaringológico de laringe sem afecção, realizaram a emissão sustentada da vogal [a] em pé e com frequência e intensidade habituais. As emissões foram analisadas pelo programa Real Time Spectrogram da Kay Pentax®, que originou um espectrograma de banda larga e outro de banda estreita para cada sujeito. Estes foram duplicados, para aumentar a fidedignidade do estudo, e enviados a três fonoaudiólogas juízas que realizaram o julgamento dos mesmos seguindo um protocolo. Os resultados foram analisados estatisticamente pelo Teste para Diferenças de Proporções com nível de significância de 5 %. RESULTADOS: na Espectrografia de Banda Larga, houve significância estatística para ruído muito presente nas frequências em torno de 3,2KHz, pouca definição do terceiro formante, pouca regularidade do traçado e anti-ressonância mediana. Na Espectrografia de Banda Estreita, houve fraca intensidade das frequências em torno de 3,2KHz e em todo espectro, ruído muito presente em todo espectro e nas frequências em torno de 3,2KHz, ruído mediano nas baixas frequências, pouca regularidade do traçado e anti-ressonância mediana. CONCLUSÃO: a análise espectrográfica dos homens adultos jovens, com laringe sem afecções e sem queixas vocais, revelou grande quantidade de ruído em todo o espectro e nas frequências em torno de 3,2KHz, terceiro formante pouco definido, ruído mediano nas baixas frequências, traçado pouco regular, anti-ressonância mediana, fraca intensidade em todo espectro e, em especial, nas frequências em torno de 3,2KHz.

Modificações vocais acústicas espectrográficas produzidas pela fonação reversa

OBJETIVO: conhecer os efeitos da técnica de fonação reversa, realizando análise da sua eficácia sobre vozes femininas normais, por meio da espectrografia acústica de banda larga e de banda estreita. MÉTODOS: 32 mulheres adultas jovens, que assinaram o Termo de Consentimento Livre e Esclarecido da pesquisa, submeteram-se à avaliação otorrinolaringológica e triagem fonoaudiológica a fim de eliminar possíveis alterações que pudessem interferir nos resultados da pesquisa. Tiveram amostras vocais coletadas antes e após realizar três séries de 15 repetições de fonação reversa em tempo máximo de fonação com tom e intensidade habituais, com 30 segundos de repouso passivo entre cada série. Utilizou-se o software Real Time Spectrogram (Kay Elemetrics Corp.) para gerar espectrogramas de banda larga e de banda estreita. Os dados obtidos foram analisados por meio de porcentagem simples e do teste do Qui-Quadrado, com nível de significância de 5%. RESULTADOS: houve tendência percentual ao aumento da definição de harmônicos, da regularidade do traçado, da intensidade e da definição dos Formantes 3 e 4, da intensidade das altas frequências e em todo o espectro; e aumento significante da definição do Formante 1. CONCLUSÃO: acredita-se que a técnica favoreça o alongamento e a vibração das pregas vocais com possível homogeneização e modificações ocorridas na mucosa, e conseqüente melhoria do sinal vocal, com maior regularidade de vibração e melhora de ressonância.

Disfonias: relação S/Z e tipos de voz

OBJETIVO: verificar o resultado da relação s/z e do tipo de voz em pacientes com diagnóstico de disfonias orgânico-funcionais (DOF) e disfonias funcionais por uso incorreto da voz (DFUIV), bem como a ocorrência das diferentes patologias dentro das DOF. MÉTODOS: 70 indivíduos, de ambos os sexos, entre cinco e 65 anos de idade, atendidos numa clínica-escola, cadastrados em Banco de Dados, entre 1998 e 2006, com DOF e DFUIV, ambos classificados em três subgrupos: casos em que a relação s/z indicava hipercontração, normalidade, e falta de coaptação das pregas vocais durante a fonação. Os tipos de voz foram classificados conforme a ocorrência em: sem alteração; ruidosa; ruidosa, comprimida e/ou apresentando alteração de f0h; ruidosa e/ou apresentando alteração de f0h; e comprimida. RESULTADOS: ocorrência significativa de DOF e de DOF com nódulos vocais; nas DOF e DFUIV, ocorrência significante de relação s/z normal com tempos isolados de /s/ e /z/ abaixo do normal e voz ruidosa. CONCLUSÕES: O resultado da relação s/z foi estatisticamente significativo a favor da faixa de normalidade estabelecida, tanto nos pacientes com diagnóstico de DOF, quanto naqueles com DFUIV, sendo que, em ambos os grupos de pacientes, a voz ruidosa foi a mais freqüente. Dentro das DOF, os nódulos vocais foram significativamente mais freqüentes do que as demais patologias.

Age-Related Changes in Long-Term Average Spectra of Children's Voices

This paper forms part of a larger study into the nature of singing development in children. The focus here is on an investigation of age-related changes in long-term average spectra (LTAS). Three hundred and twenty children in age groups 4-11 years learned a song. Each child was then digitally recorded singing alone. LTAS curves were calculated from the recordings of each voice and perceived age was estimated by a panel of independent judges. Progressive statistically significant changes were observed in the LTAS as a function of increasing age of the children. These took the form of increases in spectral energy in all frequencies below 5.75 kHz, with concomitant reductions of energy in frequency regions above this point. Increases with age were also found in overall intensity levels of the vocal products. Four experienced listeners audited the voice samples and made estimates of the children's ages. The level of accuracy of age-estimates was remarkably high for children in the youngest age groups, but was reduced with voice samples from older children. Maturation and developing competence of the vocal system, both in growth of lung capacity and at a laryngeal level, are implicated in the generation of age-related spectral changes. Perceived child singer age appears to be less closely related to spectral characteristics (as defined within LTAS) with increasing age of children.

Efeitos do som basal em fendas glóticas

TEMA: som basal em fendas glóticas. PROCEDIMENTOS: participaram desta pesquisa dois sujeitos do sexo feminino, com idades entre 20 e 40 anos e diagnóstico otorrinolaringológico de fenda em ampulheta. Houve gravação da emissão sustentada da vogal /a/ e exame videolaringoestroboscópico, imediatamente a seguir, os sujeitos realizaram o som basal em três séries de 15 repetições, e foram submetidos a novo exame laríngeo e gravação da vogal. Os dados pré e pós-realização do som basal foram submetidos às analises acústica, perceptivo-auditiva e videolaringoestroboscópica, realizadas por juízes (três fonoaudiólogas e três otorrinolaringologistas, respectivamente). RESULTADOS: em ambos os sujeitos, houve melhora no fechamento glótico e amplitude de vibração da mucosa das pregas vocais; piora no tipo de voz; aumento das medidas de ruído e de Jitter. CONCLUSÃO: o som basal promoveu redução das fendas glóticas e aumento da amplitude de vibração da mucosa das pregas vocais; piora do tipo de voz, que ficou mais ruidoso; aumento das medidas de ruído e de Jitter, sugerindo irregularidade vibratória, provavelmente devido ao efeito do ajuste do som basal ao mobilizar intensamente a mucosa.

Perfil vocal do guia de turismo

OBJETIVO: caracterizar o perfil vocal dos guias de turismo, bem como gênero e idade. MÉTODOS: participaram desse estudo 23 guias de turismo, de ambos os gêneros, com idade entre 25 a 64 anos, participantes do Sindicato de Guias de Turismo do Estado de Pernambuco, que compareceram às reuniões trimestrais no período da coleta. Trata-se de um estudo de caráter descritivo, observacional e transversal. Para coleta foi realizada avaliação perceptivo-auditiva GRBAS. RESULTADOS: observou-se que a maioria dos guias apresentou loudness adequada, pitch normal e voz alterada. Além disso, as médias dos tempos máximos de fonação das vogais e das fricativas encontravam-se reduzidas e ataque vocal isocrônico. A ressonância, na maioria dos guias, estava equilibrada, mas houve uma incidência de ressonância laringo-faringea. A articulação foi precisa, com tipo e modo respiratório misto e nasal, respectivamente. Quanto à escala GRBAS as alterações apareceram de forma leve no G (grau de alteração vocal) em 68%. CONCLUSÃO: na amostra estudada, a maioria era do gênero feminino com média de idade de 46 anos, e perfil vocal caracterizado por tempo máximo de fonação reduzidos, relação s/z adequado, ataque vocal isocrônico, pitch normal, loudness adequado, qualidade vocal alterada, com presença de rouquidão, soprosidade, tensão. A ressonância da maioria estava equilibrada e a articulação precisa, com tipo e modo respiratório misto e nasal, respectivamente. Quanto à escala GRBAS, as alterações apareceram de forma leve no grau de alteração vocal (G) em 68% e tensão (S) em 78% dos sujeitos.