Conselho Nacional de Desenvolvimento Científico e Tecnológico / Vocal exercises semioccluded vocal tract (SOVT) of include finger kazoo (FK). Objectives: to correlate vocal-acoustic and auditory perception modifications of the glottal source, spectrograph acoustic vocal modifications and self-evaluation after FK. Methods: A cross-sectional analytic quantitative observation study. The 46 adult women age between 18 and 40 without vocal complaints and laryngeal alterations, emitted the vowel /a:/ before (M1); immediately after three series of 15 FK repetitions (30 seconds rest) (M2); and five minutes after (M3); vocal self-evaluation in M2 and M3. Vocal analyses by means of the RASATI scale, programs Multi Dimension Voice Program Advanced and Real Time Spectrogram (Kay Pentax®). The spectrographs and the RASATI results were evaluated by judges. Kappa, Friedman, Wilcoxon and Chi-square tests. Results: Increase of fundamental frequency (f0); reduction of amplitude variation (vAm); and degree of sub-harmonics (DSH) in M2. No difference in the RASATI. Significant positive correlations: standard deviation of the f0 (STD) with breathiness and asthenia; measures of jitter, frequency variation (vf0) and soft phonation index (SPI) with hoarseness, breathiness, asthenia, and instability; measures of shimmer and vAm with hoarseness and breathiness; vAm with asthenia; degree and number of unvoiced segments (NUV and DUV) with breathiness; STD, jita, SPI, smoothed pitch perturbation quotient (sPPQ), smoothed amplitude perturbation quotient (sAPQ), vf0 and vAm with instability. Significant negative correlations: voice turbulence index (VTI) with asthenia; jitter and SPI measures with tension; f0 higher (fhi), f0 lower (flo) and f0 with hoarseness and breathiness; instability with flo. Wideband: improvement of F2, F3, F4 intensity and of high frequencies (hf), F2, F3 definition and trace regularity (M1XM2); F and hf intensity, and F3, F4 definition, increase in hf noise (M1XM3), worsening in the trace regularity (M2XM3). No alteration (NA) in F bandwidth, F1 definition, low, medium and hf noise (M1XM2XM3), and medium and low frequencies M1XM3). Narrowband: improvement in hf intensity, harmonics definitions and trace regularity, NA in noise between low harmonics and hf (M1XM2); improvement of hf intensity, in all vocal spectrogram and trace regularity, worsening in noise between harmonics, NA in low and hf noise, harmonics substitution for noise in all vocal spectrogram and low, medium and hf (M1XM3); NA in the presence of subharmonics (M1XM2XM3). Improvement in voice reference. Positive correlation between better voice and F3 intensity (wideband M1XM3), and harmonics substitution for noise in medium frequencies, definition and harmonics number (narrowband - M1XM3). Conclusion: FK generated noise reduction, increase of f0, vocal stability and harmonic energy. In general, hoarseness, asthenia, breathiness and instability positively correlated with jitter, shimmer, STD, SPI, vf0, vAm, NUV, DUV measures and negatively with frequency and VTI measures. The tension negatively correlated with jitter and SPI measures. There was an increase in hf intensity, F intensity and definition, trace regularity and harmonics definition. Better voice, according to F3 intensity, definition and number of harmonics and harmonics substitution for noise in medium frequencies. Keywords: Voice. Phonation. Rehabilitation. Speech Acoustics / Exercícios fonoterapêuticos de trato vocal semiocluído (ETVSO) incluem o finger kazoo (FK). Objetivo: correlacionar modificações vocais acústicas e perceptivo-auditivas de fonte glótica e modificações vocais espectrográficas e autoavaliação vocal após FK. Métodos: Estudo observacional transversal analítico quantitativo. Amostra de 46 mulheres adultas entre 18 e 31 anos de idade sem queixas vocais e afecções laríngeas. Coleta de /a:/ antes (M1); imediatamente após três séries de 15 repetições do FK (30 segundos de repouso) (M2); e cinco minutos após (M3); autoavaliação vocal em M2 e M3. Análises pela escala RASATI, programas Multi Dimension Voice Program Advanced e Real Time Spectrogram (Kay Pentax®). As espectrografias e os resultados da RASATI foram avaliados por juízes. Testes de Kappa, Friedman, Wilcoxon e Qui-quadrado. Resultados: Aumento significativo da frequência fundamental (f0), redução da variação de amplitude (vAm) e grau de sub-harmônicos (DSH) em M2. RASATI sem significâncias. Correlações positivas significativas: desvio-padrão f0 (STD) com soprosidade e astenia; medidas de jitter, variação de frequência (vf0) e índice de fonação suave (SPI) com rouquidão, soprosidade, astenia e instabilidade; medidas de shimmer e vAm com rouquidão e soprosidade; vAm com astenia; grau e número de segmentos não sonorizados (DUV e NUV) com soprosidade; STD, jita, SPI, quociente de perturbação do pitch suavizado (sPPQ), quociente de perturbação da amplitude suavizado (sAPQ), vf0 e vAm com instabilidade. Correlações negativas significativas: índice de turbulência (VTI) com astenia; medidas de jitter e SPI com tensão; f0 mais aguda (fhi), f0 mais grave (flo) e f0 com rouquidão e soprosidade; instabilidade com flo. Banda larga (EBL): melhora da intensidade F2, F3, F4 e altas frequências (af), definição F2, F3 e regularidade do traçado (M1XM2); intensidade de dos F e af, e definição F3, F4, aumento do ruído af (M1XM3); piora da regularidade do traçado (M2XM3). Sem alterações (SA) largura de banda dos F, definição F1, ruído baixas, médias e af (M1XM2XM3), e médias e baixas frequências (M1XM3). Banda estreita (EBE): melhora da intensidade af, definição harmônicos e regularidade do traçado, SA ruído entre harmônicos baixas e af (M1XM2); melhora da intensidade af, de todo espectrograma vocal e regularidade do traçado, piora do ruído entre harmônicos, SA ruído baixas e af, substituição de harmônicos por ruído em todo espectrograma vocal e baixas, médias e af (M1XM3); SA presença de sub-harmônicos (M1XM2XM3). Referência de voz melhor. Correlação positiva entre voz melhor e intensidade F3 (EBL - M1XM3), e substituição de harmônicos por ruído nas médias frequências, definição e número de harmônicos (EBE - M1XM3). Conclusão: FK gerou redução do ruído, aumento da f0, estabilidade vocal e energia harmônica. No geral, rouquidão, astenia, soprosidade e instabilidade correlacionaram-se positivamente com medidas de jitter, shimmer, STD, SPI, vf0, vAm, NUV, DUV e negativamente com medidas de frequência e VTI. A tensão correlacionou-se negativamente com medidas de jitter e SPI. Aumento da intensidade das af, intensidade e definição dos F, regularidade do traçado e definição dos harmônicos. Melhor voz, conforme aumento da intensidade F3, definição e número de harmônicos e substituição de harmônicos por ruído nas médias frequências.

Disfonia é a principal sequela cirúrgica do paciente submetido à laringectomia parcial vertical (LPV) com presença de ruído glótico intenso o que dificulta a análise acústica convencional. Por esse motivo a análise não linear (ANL), teoria dinâmica de sistemas não lineares aplicada a séries temporais não lineares, tem sido recentemente adotada como uma nova abordagem para avaliação acústica vocal. Objetivo: aplicar a ANL por meio da escala L-IE na análise acústica da voz de pacientes submetidos à LPV. Método: foram analisadas 31 vozes de pacientes submetidos à LPV, denominado de grupo de pacientes (GP) e 31 vozes de indivíduos sem alteração vocal ou laríngea, denominado grupo controle (GC). Os gráficos bidimensionais gerados a partir dos sinais de voz foram avaliados com base na técnica dos padrões visuais da dinâmica vocal (PVDV), por meio da escala de classificação L-IE para os três parâmetros: número de laços (L), irregularidade (I) e espaçamento (E). Para a correlação dos dados da ANL com a avaliação perceptivo-auditiva da voz, as vozes do GP foram avaliadas por meio da escala GRBAS. Resultados: houve correlação significativa (p<0,05) entre os três parâmetros da escala L-IE para a análise total da amostra GP e GC. Os resultados da escala L-IE para a maioria do pacientes do GP se caracterizaram por: número de laços zero; irregularidade e espaçamento dos traçados, ambos com grau 6. O GP teve a maioria de suas vozes avaliadas com grau 3 de disfonia na escala GRBAS. Houve correlação estatisticamente significante (p<0,05) entre a escala L-IE e a GRBAS nos seguintes parâmetros: o \"L\" com o grau global da disfonia (G) e com soprosidade (B) e o \"I\" com a soprosidade (B). Conclusão: o método da ANL por meio da escala L-IE, se mostrou eficiente na avaliação das vozes de pacientes submetidos a LPV. / Dysphonia is the main surgical sequel in patients who underwent vertical partial laryngectomy (VPL) with the presence of intense glottal noise which makes more difficult conventional acoustic analysis. Therefore the nonlinear analysis, dynamic theory of nonlinear systems applied to nonlinear time series, has recently been adopted as a new approach to acoustic analysis of voice. Objective: apply to ANL by L- IS scale on acoustic voice analysis of patients underwent VPL. Method: 31 voices of patients underwent VPL called patient group (PG) and 31 voices of individuals without vocal or laryngeal disorder were analyzed called control group (CG). Two-dimensional graphs generated from the voice signals the both groups were evaluated based on the technique of VDVP through the rating scale L-IS for the three parameters: number of loops (L), irregularity (I) and spacing (S). For the correlation of data from nonlinear analysis with the perceptual evaluation, the voices of the PG were evaluated by GRBAS scale. Results: significant correlation (p <0.05) between the three parameters of the L-IS scale for the total sample analysis PG and CG. The results of the L-IS scale for the majority of PG patients were characterized by: zero for number of loops; 6 degree for both irregularity and spacing of the traces. The PG had most of their voices evaluated with 3 degree of dysphonia in GRBAS. There was a statistically significant correlation (p<0.05) between L-IS and GRBAS parameters: \"L\" with the overall grade of dysphonia (G) and breathiness (B) and \"I\" with breathiness (B). Conclusion: the method of ANL by L-IS scale, is efficient for evaluating the voices of patients underwent VPL.

This study examined kinematic and acoustic adaptation following the placement of electromagnetic articulography (EMA) sensors, which measure speech articulator movements. Sixteen typical native English speakers had eight EMA sensors attached to obtain kinematic data: three to the tongue (front, mid, and back at midline), one on the lower incisors (jaw), two on the lips (one on each lip at midline), and two reference sensors on the eyeglass frames worn by the participants. They repeated the same sentence stimuli 5 times every two minutes (0, 2, 4, 6 minutes post-attachment) while both acoustic and kinematic data were recorded. Global kinematic measures of tongue activity were computed using articulatory stroke metrics, while point measures were gathered from one syllable in the target sentence. The first two formant frequencies of that syllable were measured. Statistical analysis revealed several significant changes over time and differences between genders. There was a significant increase in the syllable speed and decrease in sentence duration over time. The first formant was significantly lower over time correlating with decreased hull area, representing higher tongue position and smaller movements as speakers adapted to the sensors. Tongue displacement during the syllable production decreased over time; there was not a significant gender difference for displacement measures. The number of articulatory strokes decreased over time, suggesting improved articulatory steadiness. It can be concluded that participants demonstrated faster, smaller movements over time, but it is not clear how much of the change was a result of kinematic adaptation or task familiarity. Future research is needed to compare the direct relationship between kinematic, acoustic, and perceptual measures in response to the attachment of these EMA sensors.

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This thesis examined the time course of speech adaptation prior to data collection when using an electromagnetic articulograph to measure speech articulator movements. The stimulus sentence and electromagnetic sensor placement were designed to be sensitive to changes in the fricatives /s/ and /ʃ/. Twenty native English speakers read aloud stimulus sentences before the attachment of six electromagnetic sensors, immediately after attachment, and again at 5, 10, 15 and 20 minutes after attachment. Participants read aloud continuously between recordings to encourage adaptation to the presence of the sensors. Audio recordings were rated by 20 native English listeners who were not part of the production study. After listening to five practice samples, these participants rated 150 stimuli (31 repeat samples) using a visual analog scale (VAS) with the endpoints labeled as precise and imprecise. An acoustic analysis of the recordings was done by segmenting the fricatives /s/ and /ʃ/ from the longer recording and computing spectral center of gravity and spectral standard deviation in Hertz. Durations of /s/, /ʃ/ and the sentence were also measured. Results of both perceptual and acoustic analysis revealed a change in speech precision over time, with all post attachment recordings receiving lower perceptual scores. Precision ratings beyond the ten minute recording remained steady. It can be concluded from the results that participants reached a height of adaptation after 10 minutes of talking with kinematic recording sensors attached, and that after the attachment of sensors, speech production precision did not at any point return to pre attachment levels.

The overarching goal of this dissertation was to assess a set of sensorimotor, acoustic, and functional speech measures to inform the understanding of the mechanisms underlying two common speech disorders with evidence of disrupted sensory function: hyperfunctional voice disorders (HVDs) and hypokinetic dysarthria resulting from Parkinson’s disease (PD). The purpose of the first and second study was to elucidate the mechanisms underlying speech symptoms in HVDs. The aim of the first study was to examine whether auditory discrimination and vocal responses to altered auditory feedback (indicative of vocal motor control) differed in a large set of speakers with HVDs (N = 62) compared to controls (N = 62). The results directly implicate disrupted auditory processing in impairments to vocal motor control in HVDs. Building on this finding, the second study sought to compare the same auditory and vocal motor control measures in speakers with HVDs pre- and post-therapy (N = 11) to assess whether successful therapy (i.e., voice symptom improvement) resulted in improvements to auditory-motor function. On average, vocal motor control improved after therapy but there were little changes to measures of auditory processing, which suggests that therapeutic improvements in HVDs may be compensatory rather than a result of resolving the underlying auditory processing deficits. The collective findings from the first and second study improve the understanding of the development of HVDs and highlight the need to consider auditory processing in assessment and treatment of HVDs. The third and fourth study objectives were to characterize auditory-motor control and longitudinal changes to speech acoustics in PD. In the third study, auditory-motor control of both voice and articulatory parameters of speech were assessed in speakers with PD on medication (N = 28) compared to controls (N = 28) and compared to measures of speech function (intelligibility and naturalness ratings). No group differences were found in auditory-motor measures, regardless of speech domain. These results, which describe findings from the largest sample of PD patients completing auditory-motor tasks to-date (N=28), suggest that auditory-motor control is intact in individuals with PD on their typical medication cycle. This work also provided the first evidence that auditory-motor measures reflect measures of speech function (speech intelligibility and naturalness). The fourth and final study in this dissertation examined whether longitudinal changes to speech acoustics in PD were associated with the specific time (in months) between speech samples. Although prior work has examined speech decline in PD, no study to-date has assessed whether speech acoustics are sensitive to disease progression within an individual with PD. The current study examined acoustic speech samples collected from speakers with PD (N = 30) at two separate time points. Longitudinal changes to speech acoustics were examined by time between speech samples, motor phenotype and sex assigned at birth, to shed light on the relationships between acoustic measures of speech, disease progression, motor symptoms, and sex. The study revealed that longitudinal decline in second formant slope, articulation rate (syllables per second) across The Rainbow Passage, and relative fundamental frequency offset values were all associated with increased time between sessions within a speaker. In addition, longitudinal increases in percent pause time in conversational speech were more likely in the PIGD motor phenotype, and longitudinal increases mean fo across conversational speech were more likely in males compared to females with PD. This work provides the first report of acoustic measures of speech that reflect the specific time, in months, of PD progression, as well as acoustic measures of speech that appear to be differentially impacted over time by motor phenotype and by sex. The findings provide evidence that three acoustic measures of speech show promise as measures of PD progression in months and support the notion that speech symptom decline differs by motor phenotype and by sex assigned at birth, which should be considered when planning therapeutic interventions. / 2024-08-31T00:00:00Z

O envelhecimento vocal é chamado de presbifonia e consiste na deterioração da voz pela idade. É resultante de um processo de modificações anatômicas e fisiológicas ocorridas na laringe e que interferem na qualidade de voz. Este estudo teve como objetivo analisar acusticamente vozes de indivíduos na terceira idade, investigando as diferenças nos parâmetros acústicos da voz entre jovens adultos e a população geriátrica. Os parâmetros acústicos vocais consistem a forma de caracterizar o sinal da voz. Realizou-se uma entrevista inicial com os participantes, posteriormente foram feitas a aquisição e análise acústica das vozes, com o intuito de obter os parâmetros quantitativos específicos. Os participantes foram divididos em dois grupos experimentais: 180 indivíduos da terceira idade e 52 jovens-adultos, de ambos os gêneros. O programa de análise acústica utilizado foi “Análise de Voz" que possui instrumentos que avaliam vários parâmetros acústicos: um osciloscópio; medidor de intensidade vocal; analisador de espectro; jitter; shimmer; nivelamento espectral de resíduos (SFR), nivelamento de filtro inverso (SFF); amplitude de pitch (PA); coeficiente de excesso (EX) e freqüência fundamental (F0). Os participantes apresentavam bom estado de saúde geral, sem a presença de patologias neurológicas e realizavam atividades sócio-culturais. A análise dos dados foi feita por meio da análise estatística descritiva e por meio do teste t para comparação entre médias. A análise dos resultados dos parâmetros acústicos da voz de homens idosos, no decorrer dos anos, permitiu concluir que a F0 apresentou um aumento na passagem da quinta para a sexta década de vida; o jitter apresentou uma acentuada queda entre a sexta e sétima década de vida; o shimmer tende a diminuir gradativa e linearmente, mostrando-se como o parâmetro acústico mais sensível à idade vocal masculina, o SFR manteve-se constante até a sétima década, apresentando um aumento de 10% entre a sétima e a oitava década de vida, o SFF manteve-se estável até a sétima década e apresentou um ligeiro aumento a partir da sétima década de vida, o PA se mantém estável no decorrer das décadas de vida e o EX permanece estável no decorrer da idade. Para as mulheres, a análise dos resultados dos parâmetros acústicos da voz, no decorrer dos anos, permitiu concluir a F0 apresentou um aumento entre a quarta e quinta década de vida. Na passagem da quinta para sexta década de vida há uma diminuição mantendo-se até a oitava década; o jitter apresentou uma tendência ao aumento ao longo das décadas; o shimmer apresentou um aumento acentuado na passagem da sétima para a oitava década de vida; o SFR tende a diminuir gradativa e linearmente, mostrando-se como parâmetro acústico mais sensível à idade feminina; o SFF apresentou uma queda acentuada na passagem da quarta para quinta década de vida, nas demais décadas não apresentou variação significativa; o PA apresentou uma queda acentuada na passagem da 9 sétima para a oitava década de vida; o EX apresentou uma queda acentuada entre a quarta e quinta década de vida. Os resultados da comparação das vozes de homens idosos e jovens permitiram concluir que o grupo de idosos apresentou F0 mais grave; as medidas de perturbação da voz (jitter e shimmer), SFF e o EX apresentaram-se maiores no grupo de idosos, o SFR e o PA apresentou uma diminuição no grupo de idoso. No que se refere às mulheres, a comparação entre mulheres idosas e jovens, permitiu concluir que o grupo de idosas apresentou F0 mais grave; as medidas de perturbação da voz (jitter e shimmer), SFR e o PA apresentaram-se menores no grupo de idosas; o SFF e o EX apresentaramse elevados no grupo de idosas / The vocal aging in called presbyphonia and consists of voice degeneration as the age increase. It results from physiologic and anatomic changes of larynx and, of course interfere on the voice quality. In this work, the voice of elderly people is acoustically analyzed and compared with acoustic parameters of young adults. Each subject was asked to pronounce the Brazilian Portuguese phoneme /a/ for nearly 5 seconds in comfortable levels of pitch and magnitude witch corresponded to his conversation natural voice. Two experimental groups has been settled for both sexes: 180 subjects of the third age and 52 young adults. It was used the software “Analise de Voz" in order to evaluate the signal spectrum, voice intensity as well as the acoustic parameters: jitter, shimmer, spectral flatness (SF), pitch amplitude (PA), excess coefficient (EX) and fundamental frequency (F0). All speakers presented apparently good health and social activities. The data was statistically analyzed by t-test and results showed that for elderly F0 increased between fifth and sixth decades of life: jitter presented an accentuated decrease between sixth and seventh decade; shimmer decays linearly with the age and seems to be the most sensitive parameter to the men age; all others parameters (SFR, SFF, PA and Ex) are insensitive to the age. The comparison between old and young men showed that F0, SFR and PA are lower for elderly people while jitter, shimmer, SFF, and EX are higher. For women the results showed that F0 increased between 4th and 5th decades, decreasing after that: jitter increased all over the time; shimmer presented a large increase between 7th and 8th decades; SFR decreased linearly and presents good correlation with women vocal age; all others parameters presented decreasing in such specific decades, SFF and Ex between 4th and 5th and PA between 7th and 8th decades. The comparison between elderly and young people allowed to conclude that SFF and EX increase with age and F0, jitter, shimmer, SFR and PA decreased as a function of age

O presente trabalho foi realizado em dois estudos. O primeiro deles (Estudo 1) teve como objetivo descrever e comparar as características acústicas das líquidas /l/; /4/ e /"do português brasileiro enquanto o segundo (Estudo 2), procurou descrever e comparar a percepção auditiva das líquidas apresentadas a juízes. Para isto, foi analisada acusticamente a produção das líquidas /l/; /4/ e /"realizada por 10 crianças sem alterações de fala e linguagem (GC), com idade compreendida entre 5:11 e 9:0 anos, e 10 com transtorno fonológico (GTF) e idade entre 5:0 e 12:0 anos. Após a avaliação fonológica, as crianças dos dois grupos foram solicitadas a repetir três vezes as sílabas /Na, Ni, Nu/; /4a, 4i, 4u/ e /"a, "i, "u/ e as palavras /se\'boNa/, /\'Nãma/, /\'mi"W, /<aka\'4\'/, /<i\'4afa/, /pa\'"asu/. A amostra de fala foi coletada e armazenada no CSL-Computarized Speech Laboratory 4300B/4500. Os parâmetros acústicos selecionados para a análise acústica do Estudo 1 foram: valores das freqüências formantes F1, F2 e F3, duração do som-alvo, duração da sílaba contendo o som-alvo, duração do som anterior (quando presente) e do subseqüente, duração da porção estável do som-alvo, valores da transição do som-alvo para a vogal subseqüente (/l/) e duração da transição do som-alvo para a vogal subseqüente (/l/), transição do som-alvo para o som inserido (/4/ e /") e do sominserido para a vogal subseqüente (/4/ e /"), duração da transição do som-alvo para o som inserido (/4/ e /"), slope (medida de velocidade de movimentação dos articuladores). Em seguida à análise dos dados, uma amostra de fala foi selecionada pela pesquisadora para o Estudo 2. Esta amostra foi apresentada a dois grupos de juízes da FMUSP, um composto por alunos do curso de graduação e outro por alunos de pós-graduação, todos fonoaudiólogos, que deveriam realizar um julgamento perceptivo-auditivo das sílabas e palavras. Os dados foram analisados estatisticamente por meio dos testes ANOVA, Teste-t e qui-quadrado (nível de significância adotado de 5%). Em relação às medidas acústicas, os resultados indicaram que as crianças do GC, de modo geral, foram capazes de produzir as sílabas e palavras solicitadas de maneira mais estável e precisa do que as crianças do GTF. A análise do slope mostrou que o GC apresentou movimentos mais rápidos e precisos, do ponto de vista articulatório, quando comparado ao GTF. Há evidencias que o GC se utilizou dos parâmetros acústicos de duração e das freqüências formantes para diferenciar uma líquida da outra, enquanto o GTF utilizou predominantemente a duração como diferenciador. Observando o comportamento acústico-articulatório do GC verificou-se que a língua apresenta uma maior movimentação ascendente e descendente durante a produção do /N/ e uma mudança ântero-posterior mais acentuada na produção do /4/. Em relação à análise perceptiva foi possível notar que, apesar do maior número de erros ter sido observado no grupo de juízes da pós-graduação, ambos tiveram mais dificuldade de julgar perceptivamente as sílabas e palavras com a líquida /4/. / The present research was divided in two different studies. The purpose of the first one (Study 1) was to describe and to compare the acoustic characteristics of the three Brazilian Portuguese liquid sounds /N/; /4/ and/"/. The aim of the second study (Study 2) was to describe and to compare the auditory perception of these liquids when presented to judges. To accomplish these two purposes, acoustic analyses were carried out of the production of /N/; /4/ and /"/ by 10 children without phonological disorders aged from 5:11 to 9:0 years old (CG) and 10 children with phonological disorders (PDG) aged between 5:0 and 12:0 years old. After a complete phonological evaluation the children in of both groups were asked to repeat three times the syllables /Na, Ni, Nu/; /4a, 4i, 4u/ e /"a, "i, "u/ and the words /se\'boNa/-onion, /\'Nãma/-mud, /\'mi"W-corn, /<aka\'4\'/-alligator, /<i\'4afa/-giraffe, /pa\'"asu/-clown. The samples were collected and stored in the CSL-Computerized Speech Laboratory 4300B/4500. The acoustic parameters selected to be analyzed for Study 1 were: formant frequencies F1, F2 and F3, duration of the target sound, duration of the syllable containing the liquid target sound, duration of the precedent (when present) and subsequent sound to the liquid, duration of the steady state from the target sound, transition of the target sound to the subsequent vowel (for /l/) and duration of transition of the target sound to the subsequent vowel (for /l/), transition of the target sound to the inserted sound (for /4/ e /") and from the target sound to the subsequent vowel (for /4/ e /"), duration of the transition from the target sound to the inserted sound (for /4/ e /") and slope analysis (measurement of rate of formantfrequency change ). After data analysis the researcher selected a speech sample for Study 2. The sample was presented to two groups of judges from FMUSP. One group was composed of graduate students and the other one by post-graduate students, all speech-pathologists. All of them were requested to perceptually judge syllables and words. Data were statistically analyzed using ANOVA, T test and chisquare (significance level adopted 5%). In general terms, results of Study 1 indicated that CG produced solicited syllables and words with more stability and precision than PDG. From the articulatory point of view, slope analysis showed that CG had steeper formant-frequency changes, and therefore presumably faster and more precise movements than PDG. Some evidence shows that CG used duration and formant frequencies to differentiate their liquid productions while PDG used duration prior to other acoustic parameters. Observing acoustic-articulatory parameters it was observed that CG presented ample ascendant and descendent movements during /N/ production while anterior and posterior movements were more visible during /4/ production. Study 2 results indicated that, even though the number of errors was greater for the post-graduation group of judges than for the graduate group, both of them presented more difficulty in perceptually judging the sound /4/ presented in syllables and words.