Data-driven analysis of nasal vowels dynamics and coordination: Results for bilabial context

One of Portuguese distinctive marks is the large inventory of nasals, including 5 nasal vowels and many diphthongs. Acoustic and articulatory studies showed nasal vowels having an initial oral part and a short nasal tail, probably related to synchronization between oral and nasal gestures. Previous studies have considered discrete descriptions with EMA-flesh points, limiting our grasp of the whole vocal tract, and preliminary work using real-time MRI (RT-MRI), considered a small framerate (14fps) and a reduced number of speakers, influencing both the time resolution to study an intrinsically dynamic process and the generalization of the outcomes. The recent advances of RT-MRI, with framerates of 50fps, have opened new possibilities for studies that can grasp a finer detail of the dynamics of nasals. However, new challenges need to be tackled to deal with the resulting large amount of data and to foster analyses that go beyond qualitative approaches to tackle a larger number of speakers. Grounded on a new RT-MRI corpus for European Portuguese, this paper explores the capabilities of recent data-driven methods, proposed for this type of RT-MRI data, to analyze dynamic aspects of nasal vowels and coordination. To this end, we consider data for 11 EP speakers and investigate vocal tract configurations, over time, and the coordination of velum and lip aperture in bilabial (oral and nasal) contexts

Dialectal variation in European Portuguese Central Vowel Perception

The present paper aims at providing empirical evidence for dialectal variation concerning the perception of the central vowel [ɐ] in European Portuguese (EP). More concretely, this study compares the perception of the contrast between [a] and [ɐ] by native speakers of two varieties of EP: 23 speakers of a northern Portuguese dialect (from the city of Braga) and 23 speakers of the Littoral Center variety of EP (from the city of Lisbon, defined as Standard European Portuguese (SEP)). Based on a discrimination test, the results show that the two groups of speakers differ with respect to the perception of the contrast between the two central vowels under investigation. The speakers of the northern variety differentiate less between the two central vowels compared to the speakers from Lisbon

On the role of oral configurations in European Portuguese nasal vowels

The characterisation of nasal vowels is not only a question ofstudying velar aperture. Recent work shows that oropharyngeal articulatory adjustments enhance the acoustics of nasal couplingor, at least, magnify differences between oral/nasal vowel congeners. Despite preliminary studies on the oral configurations of nasal vowels, for European Portuguese, a quantitative analysis is missing, particularly one to be applied systematically to a desirably large number of speakers. The main objective ofthis study is to adapt and extend previous methodological advances for the analysis of MRI data to further investigate: howvelar changes affect oral configurations; the changes to the articulators and constrictions when compared with oral counteparts; and the closest oral counterpart. High framerate RT-MRIimages (50fps) are automatically processed to extract the vocal tract contours and the position/configuration for the different articulators. These data are processed by evolving a quantitative articulatory analysis framework, previously proposed by the authors, extended to include information regarding constrictions (degree and place) and nasal port. For this study, while the analysis of data for more speakers is ongoing, we considered a set of two EP native speakers and addressed the study of oral and nasal vowels mainly in the context of stop consonants

Towards a Multimodal Silent Speech Interface for European Portuguese

Automatic Speech Recognition (ASR) in the presence of environmental noise is still a hard problem to tackle in speech science (Ng et al., 2000). Another problem well described in the literature is the one concerned with elderly speech production. Studies (Helfrich, 1979) have shown evidence of a slower speech rate, more breaks, more speech errors and a humbled volume of speech, when comparing elderly with teenagers or adults speech, on an acoustic level. This fact makes elderly speech hard to recognize, using currently available stochastic based ASR technology. To tackle these two problems in the context of ASR for HumanComputer Interaction, a novel Silent Speech Interface (SSI) in European Portuguese (EP) is envisioned.info:eu-repo/semantics/acceptedVersio

Towards a silent speech interface for Portuguese: Surface electromyography and the nasality challenge

A Silent Speech Interface (SSI) aims at performing Automatic Speech Recognition (ASR) in the absence of an intelligible acoustic signal. It can be used as a human-computer interaction modality in high-background-noise environments, such as living rooms, or in aiding speech-impaired individuals, increasing in prevalence with ageing. If this interaction modality is made available for users own native language, with adequate performance, and since it does not rely on acoustic information, it will be less susceptible to problems related to environmental noise, privacy, information disclosure and exclusion of speech impaired persons. To contribute to the existence of this promising modality for Portuguese, for which no SSI implementation is known, we are exploring and evaluating the potential of state-of-the-art approaches. One of the major challenges we face in SSI for European Portuguese is recognition of nasality, a core characteristic of this language Phonetics and Phonology. In this paper a silent speech recognition experiment based on Surface Electromyography is presented. Results confirmed recognition problems between minimal pairs of words that only differ on nasality of one of the phones, causing 50% of the total error and evidencing accuracy performance degradation, which correlates well with the exiting knowledge.info:eu-repo/semantics/acceptedVersio

SINGING PORTUGUESE NASAL VOWELS: PRACTICAL STRATEGIES FOR MANAGING NASALITY IN BRAZILIAN ART SONGS

The articulation of Portuguese nasalized vowels poses some articulatory problems accompanied by negative acoustic effects for the performance of Brazilian art songs. The main objective was to find strategies that permit the singer to conciliate an idiomatic pronunciation of these vowels with a well-balanced resonance, a desirable quality in classical singing. In order to devise these strategies, the author examined sources dealing with nasalized vowels from varied perspectives: acoustic properties of vowel nasalization, phonetic and phonological aspects ofBrazilian Portuguese (BP), historical views on nasality in singing, and recent vocal pedagogy research. In addition to the overall loss of sonority, the main effect of nasalization is felt mainly in the first formant (F1) region of oral vowels, due to the introduction of nasal formants and antiformants, and to shifts in the tongue posture. Several sources report the existence of a nasality contour in BP, by which a nasalized vowel starts with an oral phase and transitions gradually to a nasal phase. The author concludes that the basic approach to sing nasalized vowels in BP is (1) to find the tongue posture corresponding to the oral vowel congener (the “core vowel”), and (2) to adjust the nasality contour in such a way that the oral portion remains prominent in order to keep the resonance balance consistent during the emission of the vowel. Once the core vowel is determined, standard vowel modification choices can be made according to voice type and the musical context in which the vowel is being sung. Some challenging excerpts from Brazilian art songs are examined, with suggestions for the application of the discussed strategies

Data-Driven Critical Tract Variable Determination for European Portuguese

Technologies, such as real-time magnetic resonance (RT-MRI), can provide valuable information to evolve our understanding of the static and dynamic aspects of speech by contributing to the determination of which articulators are essential (critical) in producing specific sounds and how (gestures). While a visual analysis and comparison of imaging data or vocal tract profiles can already provide relevant findings, the sheer amount of available data demands and can strongly profit from unsupervised data-driven approaches. Recent work, in this regard, has asserted the possibility of determining critical articulators from RT-MRI data by considering a representation of vocal tract configurations based on landmarks placed on the tongue, lips, and velum, yielding meaningful results for European Portuguese (EP). Advancing this previous work to obtain a characterization of EP sounds grounded on Articulatory Phonology, important to explore critical gestures and advance, for example, articulatory speech synthesis, entails the consideration of a novel set of tract variables. To this end, this article explores critical variable determination considering a vocal tract representation aligned with Articulatory Phonology and the Task Dynamics framework. The overall results, obtained considering data for three EP speakers, show the applicability of this approach and are consistent with existing descriptions of EP sounds

Validity and reliability of the 2nd European Portuguese version of the “Consensus Auditory-Perceptual Evaluation of Voice” (II EP CAPE-V)

A thesis submitted in partial fulfillment of the requirement for the degree of Master in Science at the Health Science School of Polytechnic Institute of SetúbalIntroduction: Auditory-perceptual evaluation of voice is a part of a multidimensional voice evaluation, and is claimed to be “golden standard”. The “Consensus Auditory-Perceptual Evaluation of Voice” (CAPE-V) has been demonstrated to be a valid and reliable instrument for voice evaluation, when applied in both clinical and scientific research fields. The CAPE-V was first translated into European Portuguese (EP) (Jesus et al., 2009) however it revealed some validity and reliability problems. The purpose of this study was to assure a valid and reliable EP version of CAPE-V. This resulted in the 2nd EP version of CAPE-V (II EP CAPE-V), with permission granted by ASHA. Method: This was a transversal, observational, descriptive, and comparative study. 14 Speech-language pathologists (SLPs) voice experts (>5 years of clinical practice), rated a total of 26 voice samples produced by 10 males (mean age=45) and 10 females (mean age=43) classified into two groups: a control group (n=10) and a dysphonic group (n=10), with subjects matched for age and gender. All voice samples were rated in one session with the II EP CAPE-V, and in a second session one week later with GRBAS. Content validity was supported by 6 new sentences conceptualized and adapted to EP linguistic and cultural context according to the rationale outlined in the original CAPE-V protocol. For construct validity analysis, an independent samples t-test (α=.05) was performed for all vocal parameter. Concurrent validity was estimated with the multi-serial correlation coefficient between II EP CAPE-V and GRBAS parameters (r>.70). Reliability was performed for all vocal parameters. Inter-rater reliability was determined by ICC, and intra-rater reliability by Pearson’s correlation coefficient (r>.70). Results/conclusion: Content validity was assured by an EP linguistic expert, who reviewed the six new sentences. Construct validity was obtained for all voical parameters (p.89) for overall severity/grade, roughness, and breathiness parameters. High inter-rater reliability (ICC>.84) was obtained for all parameters. Intra-rater reliability was high (r>.87) for overall severity, breathiness, and pitch; good (r=.73) for strain; and moderate (r>.69) for roughness and loudness parameters. The II EP CAPE-V is a valid and reliable instrument for auditory-perceptual evaluation, with all psychometric characteristics established

Normative nasalance values across languages.

The Nasometer is an objective computer-based instrument designed to measure the acoustic correlates of resonance and velopharyngeal function. The device has proven to be useful for early identification of persons at risk for velopharyngeal dysfunction. Since its introduction, the Nasometer has been used in craniofacial centers and other clinical settings both in the United States and around the world. The purpose of this paper is to describe the Nasometer and its clinical uses, discuss speaker characteristics that might influence nasalance values, and provide a compilation of published normative nasalance data across English, Spanish, Asian, and European languages. Additionally, languages in need of normative nasalance data are discussed

Envelhecimento vocal: estudo acústico-articulatório das alterações de fala com a idade

Background: Although the aging process causes specific alterations in the speech organs, the knowledge about the age effects in speech production is still disperse and incomplete. Objective: To provide a broader view of the age-related segmental and suprasegmental speech changes in European Portuguese (EP), considering new aspects besides static acoustic features, such as dynamic and articulatory data. Method: Two databases, with speech data of Portuguese adult native speakers obtained through standardized recording and segmentation procedures, were devised: i) an acoustic database containing all EP oral vowels produced in similar context (reading speech), and also a sample of semispontaneous speech (image description) collected from a large sample of adults between the ages 35 and 97; ii) and another with articulatory data (ultrasound (US) tongue images synchronized with speech) for all EP oral vowels produced in similar contexts (pseudowords and isolated) collected from young ([21-35]) and older ([55-73]) adults. Results: Based on the curated databases, various aspects of the aging speech were analyzed. Acoustically, the aging speech is characterized by: 1) longer vowels (in both genders); 2) a tendency for F0 to decrease in women and slightly increase in men; 3) lower vowel formant frequencies in females; 4) a significant reduction of the vowel acoustic space in men; 5) vowels with higher trajectory slope of F1 (in both genders); 6) shorter descriptions with higher pause time for males; 7) faster speech and articulation rate for females; and 8) lower HNR for females in semi-spontaneous speech. In addition, the total speech duration decrease is associated to non-severe depression symptoms and age. Older adults tended to present more depressive symptoms that could impact the amount of speech produced. Concerning the articulatory data, the tongue tends to be higher and more advanced with aging for almost all vowels, meaning that the vowel articulatory space tends to be higher, advanced, and bigger in older females. Conclusion: This study provides new information on aging speech for a language other than English. These results corroborate that speech changes with age and present different patterns between genders, and also suggest that speakers might develop specific articulatory adjustments with aging.Contextualização: Embora o processo de envelhecimento cause alterações específicas no sistema de produção de fala, o conhecimento sobre os efeitos da idade na fala é ainda disperso e incompleto. Objetivo: Proporcionar uma visão mais ampla das alterações segmentais e suprassegmentais da fala relacionadas com a idade no Português Europeu (PE), considerando outros aspetos, para além das características acústicas estáticas, tais como dados dinâmicos e articulatórios. Método: Foram criadas duas bases de dados, com dados de fala de adultos nativos do PE, obtidos através de procedimentos padronizados de gravação e segmentação: i) uma base de dados acústica contendo todas as vogais orais do PE em contexto semelhante (leitura de palavras), e também uma amostra de fala semiespontânea (descrição de imagem) produzidas por uma larga amostra de indivíduos entre os 35 e os 97 anos; ii) e outra com dados articulatórios (imagens de ultrassom da língua sincronizadas com o sinal acústico) de todas as vogais orais do PE produzidas em contextos semelhantes (pseudopalavras e palavras isoladas) por adultos de duas faixas etárias ([21-35] e [55-73]). Resultados: Tendo em conta as bases de dados curadas, foi analisado o efeito da idade em diversas características da fala. Acusticamente, a fala de pessoas mais velhas é caracterizada por: 1) vogais mais longas (ambos os sexos); 2) tendência para F0 diminuir nas mulheres e aumentar ligeiramente nos homens; 3) diminuição da frequência dos formantes das vogais nas mulheres; 4) redução significativa do espaço acústico das vogais nos homens; 5) vogais com maior inclinação da trajetória de F1 (ambos os sexos); 6) descrições mais curtas e com maior tempo de pausa nos homens; 7) aumento da velocidade articulatória e da velocidade de fala nas mulheres; e 8) diminuição do HNR na fala semiespontânea em mulheres. Além disso, os idosos tendem a apresentar mais sintomas depressivos que podem afetar a quantidade de fala produzida. Em relação aos dados articulatórios, a língua tende a apresentar-se mais alta e avançada em quase todas as vogais com a idade, ou seja o espaço articulatório das vogais tende a ser maior, mais alto e avançado nas mulheres mais velhas. Conclusão: Este estudo fornece novos dados sobre o efeito da idade na fala para uma língua diferente do inglês. Os resultados corroboram que a fala sofre alterações com a idade, que diferem em função do género, sugerindo ainda que os falantes podem desenvolver ajustes articulatórios específicos com a idade.Programa Doutoral em Gerontologia e Geriatri