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Audio-based classification techniques on body sounds have long been studied to support diagnostic decisions, particularly in pulmonary diseases. In response to the urgency of the COVID-19 pandemic, a growing number of models are developed to identify COVID-19 patients based on acoustic input. Most models focus on cough because the dry cough is the best-known symptom of COVID-19. However, other body sounds, such as breath and speech, have also been revealed to correlate with COVID-19 as well. In this work, rather than relying on a specific body sound, we propose Fused Audio Instance and Representation for COVID-19 Detection (FAIR4Cov). It relies on constructing a joint feature vector obtained from a plurality of body sounds in waveform and spectrogram representation. The core component of FAIR4Cov is a self-attention fusion unit that is trained to establish the relation of multiple body sounds and audio representations and integrate it into a compact feature vector. We set up our experiments on different combinations of body sounds using only waveform, spectrogram, and a joint representation of waveform and spectrogram. Our findings show that the use of self-attention to combine extracted features from cough, breath, and speech sounds leads to the best performance with an Area Under the Receiver Operating Characteristic Curve (AUC) score of 0.8658, a sensitivity of 0.8057, and a specificity of 0.7958. This AUC is 0.0227 higher than the one of the models trained on spectrograms only and 0.0847 higher than the one of the models trained on waveforms only. The results demonstrate that the combination of spectrogram with waveform representation helps to enrich the extracted features and outperforms the models with single representation.

The goal of this work was the articulatory-acoustic characterization of nasality: the nature of velopharyngeal port movement and associated acoustic characteristics. The building of a 3D linear single-subject articulatory model of the nasal tract from MRI and CT images revealed two degrees of freedom for the movements of the velum and nasopharyngeal wall. The dominant parameter corresponds to a joint vertical oblique movement of the velum and a horizontal movement of the pharyngeal wall, expressing the sphincter effect of the velopharyngeal port. The second parameter corresponds to a smaller movement of the velum, significantly modifying the nasal coupling area. The space covered by the model's movements corresponds precisely to that described by a velum point measured by electromagnetic articulography. Realistic area functions of the nasal tract derived from the model allowed us to determine acoustic transfer functions for seven vowels and the acoustic influence of velar movements., Ce travail a pour objectif la caractérisation articulatori-acoustique de la nasalité: nature des mouvements du port vélopharyngé, caractéristiques acoustiques liées. La construction d'un modèle articulatoire linéaire 3D monosujet du conduit nasal à partir d'images IRM et CT a fait émerger deux degrés de liberté parmi les mouvements du voile du palais et de la paroi nasopharyngée. Le premier, prédominant, correspond à un mouvement conjoint vertical oblique du voile et horizontal de la paroi pharyngée, traduisant l'effet de sphincter du port vélopharyngé, et le second à un petit mouvement horizontal du voile seul, modifiant sensiblement l'aire de couplage nasal. L'espace des mouvements du modèle décrit exactement celui d'un point du voile obtenu par articulographie électromagnétique. Les fonctions d'aire réalistes du conduit nasal déduites du modèle ont permis de déterminer les fonctions de transfert acoustiques de sept voyelles et l'influence acoustique des mouvements du voile.

This paper describes the processing of MRI and CT images needed for developing a 3D linear articulatory model of velum. The 3D surface that defines each organ constitutive of the vocal and nasal tracts is extracted from MRI and CT images recorded on a subject uttering a corpus of artificially sustained French vowels and consonants. First, the 2D contours of the organs have been manually extracted from the corresponding images, expanded into 3D contours, and aligned in a common 3D coordinate system. Then, for each organ, a generic mesh has been chosen and fitted by elastic deformation to each of the 46 3D shapes of the corpus. This has finally resulted in a set of organ surfaces sampled with the same number of 3D vertices for each articulation, which is appropriate for Principal Component Analysis or linear decomposition. The analysis of these data has uncovered two main uncorrelated articulatory degrees of freedom for the velum's movement. The associated parameters are used to control the model. We have in particular investigated the question of a possible correlation between jaw / tongue and velum's movement and have not find more correlation than the one found in the corpus., ZAS Papers in Linguistics, Bd. 40 (2005): Speech production and perception: experimental analyses and models

International audience; The end of the twentieth century and the beginning of this one saw a reorganization of research in the field of speech and language emergence (SLE). Naturalism is the core of this new approach. It consists in describing the relations between biological aspects (in every sense of the word) on the one hand and speech and language, on the other hand, by an accumulation of hypotheses and evidence derived from a wide range of data collected by means of interdisciplinary collaborations. As with studies on the origin of man, a profusion of hypotheses has arisen, which sometimes lead to very dubious developments, based on flimsy results and on too little data, and connected to related but not fully mastered or overly simplified disciplines. This is why regular critical overviews do not seem superfluous. First, we propose a classification (push and pull theory) that provides a new reading of the various theories which have been proposed for half a century. In the present state of knowledge, it is not possible to infer when our ancestors acquired the faculty of speech and language: control of speech articulators, coordination between larynx and vocal tract, phonology, syntax, semantics, and recursion. Some longstanding questions remain unanswered: Why is our species alone in having speech and language? Many other questions are (for now) badly formulated problems: we do not have sufficient data to answer them. Perhaps these questions will remain unanswered. But we think that the following question can be answered: If we suppose that our ancestors (and distant cousins) controlled their larynx and vocal tract in the same way as present-day humans, did the geometry of their vocal tract allow them to produce the universal sound structures of the languages spoken today? We analyzed 32 skulls from the present to 1.6 Ma (million years) BP (before present) of fossil hominids available at the Musée de l'Homme in Paris or in the literature: (1) 10-30 ka (thousand years) BP: modern humans: Paleolithic; (2) 90-200 ka BP: anatomically modern humans; (3) 45-90 ka BP: Neanderthals; (4) 1.6 Ma BP: Homo ergaster. These skulls are all well preserved and most possess a mandible but the vertebral column has been reconstructed from some fossil vertebrae. We attempt to: (1) identify the position of the hyoid bone and glottis; (2) reconstruct a vocal tract in a plausible way using an articulatory model; (3) quantify the acoustic capabilities of this reconstructed vocal tract. For this purpose, we combine phylogeny and ontogeny. We can now state that our ancestors and distant cousins were equipped with a vocal tract that could produce the same variety of vowel sounds as we can today: mainly the vowels /i a u/. Vocal tract morphology has allowed for the emergence and production of speech for several hundred thousand years. But how can we know to what extent earlier hominids mastered the control skills needed to produce speech? New lines of research are proposed in which orofacial abilities necessary to the emergence of speech are linked to a precursor mechanism dedicated to feeding (masticating-swallowing gestures).

International audience; Fetal dosimetry studies require thedevelopment of accurate 3D models of the fe-tus. This paper proposes a 3D articulated fe-tal growth model including skeleton, body en-velope, brain and lungs based on medical im-ages of 10 dierent fetuses acquired in clinicalroutine. The structures of interest were semi-manually segmented from the images and sur-face meshes were generated. A generic mesh ofeach structure has been deformed towards thesegmented ones. By interpolating linearly be-tween the subjects of the database, each struc-ture can be estimated at any age and in anyposition. This process results in an automatedmodel, the operator being only required tospecify the age and position of the desired es-timated fetus.

La fin du XXe et le tout début de ce siècle révèlent une véritable réarticulation des recherches dans le domaine de l’émergence de la parole et du langage. Le naturalisme, qui est au centre de cette approche, se propose de décrire les relations entre la biologie (au sens très large du terme) d’une part, la parole et le langage, d’autre part, par une accumulation d’hypothèses, de données et de preuves formulées et établies grâce à de multiples collaborations interdisciplinaires. Comme pour les travaux sur l’origine de l’Homme (la découverte d’un nouveau fossile entraînant souvent une remise en question des théories précédentes), on assiste à un foisonnement théorique qui entraîne parfois des développements très hypothétiques, s’appuyant sur des résultats fragiles et sur trop peu de données, proposés dans des disciplines connexes mais non maîtrisées ou trop simplifiées. C’est pourquoi les bilans réguliers, les mises en perspectives critiques ne nous semblent pas superflus.Dans un premier temps nous proposerons une classification qui permet une lecture des différentes théories proposées depuis un demi-siècle (théorie push-pull). Dans l’état actuel des connaissances, il n’est pas possible d’inférer quand nos ancêtres, voire nos lointains ont acquis la faculté de langage et de parole : le contrôle des articulateurs, la coordination entre le larynx et le conduit vocal, la phonologie, la syntaxe, la sémantique et la récursivité. Parmi les questions qui se posent, il en est une qui reste sans réponse : pourquoi notre espèce est actuellement la seule à posséder langue et parole ? De nombreuses questions font partie des problèmes mal posés, comme le sont les questions du type: Quelle(s) langue(s) parlaient nos prédécesseurs ? Possédaient-ils une langue unique ? En effet, on ne dispose pas (pour le moment) de suffisamment de données pour pouvoir y répondre. Peut-être même que ces questions ne trouveront pas de solution. Actuellement, il est quand même possible de répondre à la question suivante : si nous supposons que nos ancêtres (et cousins lointains) contrôlaient leur larynx et leur conduit vocal de la même manière que les Hommes actuels, est-ce que la géométrie de leur conduit leur permettaient de produire les structures sonores qui sont pratiquement présentes dans toutes les langues du monde ?Nous présenterons ensuite nos travaux qui participent à la nouvelle réarticulation avec une approche véritablement axée sur la pluridisciplinarité. Ils s’inscrivent dans le domaine des relations entre la morphologie des organes de la production de la parole et son contrôle. Nous présentons de nouveaux résultats concernant la croissance du conduit vocal de la naissance à l’âge adulte puis des reconstructions du conduit vocal pour des fossiles qui couvrent la période de 10.000 ans à un million et demi d’années BP (Before Present). À partir du crâne, de la mandibule et des vertèbres cervicales nous essaierons de manière plausible (1) de localiser l’os hyoïde, support de la langue, et la position de la glotte, (2) de reconstituer un conduit vocal, à l’aide d’un modèle articulatoire, (3) d’induire les possibilités acoustiques de tous ces conduits. En combinant phylogenèse et ontogenèse il est possible de représenter l’anatomie du tractus en synthétisant deux remodelages qui renvoient à l’ontogenèse et à la phylogenèse. Nous montrerons que tous ces conduits ont les mêmes potentialités acoustiques, ils peuvent produire les voyelles /i a u/ qui sont pratiquement présentes dans toutes les langues du monde : un triangle à l’intérieur duquel se situent toutes les autres voyelles. Quand aux consonnes les plus fréquentes /p t k/, /b d g/ elles sont aussi à la portée de tous ces conduits vocaux à partir de gestes de fermeture dans des régions précises (lèvres, zone alvéodentale, zone vélaire). De nouvelles pistes de recherche sont proposées qui tendraient à montrer qu’il y a vraisemblablement plusieurs centaines de milliers, voire plusieurs millions d’années que le conduit vocal présente une morphologie favorable à l’émergence et à la production de la parole. Un cadre est posé dans lequel les capacités orofaciales nécessaire à la parole pourraient être reliées au mécanisme précurseur d’ingestion (mastication-déglutition). The end of the XXth century and the beginning of this century saw a reorganization of the researches in the field of speech and language emergence (SLE). Naturalism is the kernel of this new approach. It consists in describing the relations between biological aspects (in every sense of the word) on the one hand and speech and language, on the other hand, by an accumulation of hypotheses and evidence derived from a huge range of data collected thanks to interdisciplinary collaborations.As is the case for researches on the origin of Man, a theoretical profusion of hypotheses has arisen which sometimes leads to very hypothetical developments, based on fragile results and on too little data, and proposed in related but not fully mastered or too much simplified disciplines. This is why regular critical overviews do not seem superfluous. First, we propose a classification (push and pull theory) that provides a new reading of the various theories which have been proposed for half a century. In the present state of knowledge it is not possible to infer when our ancestors acquired the FacultyofSpeechandLanguageandSpeech: control of speech articulators, coordination between larynx and vocal tract, phonology, syntax, semantic and recursivity. Among old unsolved questions: Why is our species alone in having speech and language? Many others questions are (for the moment?) ill posed problems: we do not have sufficiently data to answer. Perhaps these questions will remain unsolved. But we think that the following question can be solved: If we suppose that our ancestors (and distant cousins) controlled their larynx and vocal tract in the same way as present-day humans, did the geometry of their vocal tract allow them to produce the universal sound structures of the languages spoken today? We analyzed 31 skulls from now to 1.5 Ma (millions years) BP (Before Present) for fossil hominids available at the Muséedel’Homme in Paris or in the literature: (1) 10-30 ka BP: modern humans: Paleolithic; (2) 90-200 ka BP: anatomically modern humans; (3) 45-90 ka BP: Neanderthals; (4) 1.5 Ma BP: Homoergaster; These skulls are all well kept and possess a jaw in the majority of cases but the vertebral column has been reconstituted. We attempt to: (1) Localize hyoid bone and then glottis position; (2) Reconstitute a vocal tract model in a plausible way using an articulatory model; (3) Quantify the acoustic capabilities of this reconstituted vocal tract. For this purpose, we combine phylogenesis and ontogenesis. We are in a position to state that our ancestors and distant cousins were equipped with a vocal tract that could produce the same variety of vowel sounds as we can today: the vowels /i a u/. The vocal tract morphology has been favorable to the emergence and production of speech since several hundreds of thousands of years. But how to know to what extent they mastered the control skills needed to produce speech? New lines of research are proposed in which orofacial abilities necessary to the emergence of speech are linked to a precursor mechanism dedicated to feeding (masticating-swallowing movements).

http://primatologie.revues.org/797; National audience; Ontogenetic and phylogenetic considerations concerning the origin of speech The end of the XXth century and the beginning of this century saw a reorganization of the researches in the field of speech and language emergence (SLE). Naturalism is the kernel of this new approach. It consists in describing the relations between biological aspects (in every sense of the word) on the one hand and speech and language, on the other hand, by an accumulation of hypotheses and evidence derived from a huge range of data collected thanks to interdisciplinary collaborations. As is the case for researches on the origin of Man, a theoretical profusion of hypotheses has arisen which sometimes leads to very hypothetical developments, based on fragile results and on too little data, and proposed in related but not fully mastered or too much simplified disciplines. This is why regular critical overviews do not seem superfluous. First, we propose a classification (push and pull theory) that provides a new reading of the various theories which have been proposed for half a century. In the present state of knowledge it is not possible to infer when our ancestors acquired the FacultyofSpeechandLanguageandSpeech: control of speech articulators, coordination between larynx and vocal tract, phonology, syntax, semantic and recursivity. Among old unsolved questions: Why is our species alone in having speech and language? Many others questions are (for the moment?) ill posed problems: we do not have sufficiently data to answer. Perhaps these questions will remain unsolved. But we think that the following question can be solved: If we suppose that our ancestors (and distant cousins) controlled their larynx and vocal tract in the same way as present-day humans, did the geometry of their vocal tract allow them to produce the universal sound structures of the languages spoken today? We analyzed 31 skulls from now to 1.5 Ma (millions years) BP (Before Present) for fossil hominids available at the Muséedel'Homme in Paris or in the literature: (1) 10-30 ka BP: modern humans: Paleolithic; (2) 90-200 ka BP: anatomically modern humans; (3) 45-90 ka BP: Neanderthals; (4) 1.5 Ma BP: Homoergaster; These skulls are all well kept and possess a jaw in the majority of cases but the vertebral column has been reconstituted. We attempt to: (1) Localize hyoid bone and then glottis position; (2) Reconstitute a vocal tract model in a plausible way using an articulatory model; (3) Quantify the acoustic capabilities of this reconstituted vocal tract. For this purpose, we combine phylogenesis and ontogenesis. We are in a position to state that our ancestors and distant cousins were equipped with a vocal tract that could produce the same variety of vowel sounds as we can today: the vowels /i a u/. The vocal tract morphology has been favorable to the emergence and production of speech since several hundreds of thousands of years. But how to know to what extent they mastered the control skills needed to produce speech? New lines of research are proposed in which orofacial abilities necessary to the emergence of speech are linked to a precursor mechanism dedicated to feeding (masticating-swallowing movements).; La fin du XXe et le tout début de ce siècle révèlent une véritable réarticulation des recherches dans le domaine de l'émergence de la parole et du langage. Le naturalisme, qui est au centre de cette approche, se propose de décrire les relations entre la biologie (au sens très large du terme) d'une part, la parole et le langage, d'autre part, par une accumulation d'hypothèses, de données et de preuves formulées et établies grâce à de multiples collaborations interdisciplinaires. Comme pour les travaux sur l'origine de l'Homme (la découverte d'un nouveau fossile entraînant souvent une remise en question des théories précédentes), on assiste à un foisonnement théorique qui entraîne parfois des développements très hypothétiques, s'appuyant sur des résultats fragiles et sur trop peu de données, proposés dans des disciplines connexes mais non maîtrisées ou trop simplifiées. C'est pourquoi les bilans réguliers, les mises en perspectives critiques ne nous semblent pas superflus. Dans un premier temps nous proposerons une classification qui permet une lecture des différentes théories proposées depuis un demi-siècle (théorie push-pull). Dans l'état actuel des connaissances, il n'est pas possible d'inférer quand nos ancêtres, voire nos lointains ont acquis la faculté de langage et de parole : le contrôle des articulateurs, la coordination entre le larynx et le conduit vocal, la phonologie, la syntaxe, la sémantique et la récursivité. Parmi les questions qui se posent, il en est une qui reste sans réponse : pourquoi notre espèce est actuellement la seule à posséder langue et parole ? De nombreuses questions font partie des problèmes mal posés, comme le sont les questions du type: Quelle(s) langue(s) parlaient nos prédécesseurs ? Possédaient-ils une langue unique ? En effet, on ne dispose pas (pour le moment) de suffisamment de données pour pouvoir y répondre. Peut-être même que ces questions ne trouveront pas de solution. Actuellement, il est quand même possible de répondre à la question suivante : si nous supposons que nos ancêtres (et cousins lointains) contrôlaient leur larynx et leur conduit vocal de la même manière que les Hommes actuels, est-ce que la géométrie de leur conduit leur permettaient de produire les structures sonores qui sont pratiquement présentes dans toutes les langues du monde ? Nous présenterons ensuite nos travaux qui participent à la nouvelle réarticulation avec une approche véritablement axée sur la pluridisciplinarité. Ils s'inscrivent dans le domaine des relations entre la morphologie des organes de la production de la parole et son contrôle. Nous présentons de nouveaux résultats concernant la croissance du conduit vocal de la naissance à l'âge adulte puis des reconstructions du conduit vocal pour des fossiles qui couvrent la période de 10.000 ans à un million et demi d'années BP (Before Present). À partir du crâne, de la mandibule et des vertèbres cervicales nous essaierons de manière plausible (1) de localiser l'os hyoïde, support de la langue, et la position de la glotte, (2) de reconstituer un conduit vocal, à l'aide d'un modèle articulatoire, (3) d'induire les possibilités acoustiques de tous ces conduits. En combinant phylogenèse et ontogenèse il est possible de représenter l'anatomie du tractus en synthétisant deux remodelages qui renvoient à l'ontogenèse et à la phylogenèse. Nous montrerons que tous ces conduits ont les mêmes potentialités acoustiques, ils peuvent produire les voyelles /i a u/ qui sont pratiquement présentes dans toutes les langues du monde : un triangle à l'intérieur duquel se situent toutes les autres voyelles. Quand aux consonnes les plus fréquentes /p t k/, /b d g/ elles sont aussi à la portée de tous ces conduits vocaux à partir de gestes de fermeture dans des régions précises (lèvres, zone alvéodentale, zone vélaire). De nouvelles pistes de recherche sont proposées qui tendraient à montrer qu'il y a vraisemblablement plusieurs centaines de milliers, voire plusieurs millions d'années que le conduit vocal présente une morphologie favorable à l'émergence et à la production de la parole. Un cadre est posé dans lequel les capacités orofaciales nécessaire à la parole pourraient être reliées au mécanisme précurseur d'ingestion (mastication-déglutition).

International audience; Two of the major functions of the human vocal tract are speaking and feeding. Ontogenetically and phylogenetically feeding tasks precede speaking tasks and it has been hypothesised that speaking movements constitute a subset of feeding movements. From ElectroMagnetic Articulography data we have extracted two estimates of the degrees of freedom of the tongue, one from a speech task and one from a feeding task. These have been used to build two corresponding articulatory models. For both tasks, about 95% of the tongue variance can be explained by 4 parameters. Contrary to the accepted behaviour for speech, for feeding tasks, the tip, mid and back regions of the tongue appear to be controlled independently. The reconstruction errors of speech and feeding articulations by the two models show slightly better efficiency for the feeding model, suggesting that the speech movements might realistically be considered a subset of the feeding movements.

National audience; The acoustic analysis of three-dimensional (3-D) geometrical vocal-tract models with nasal coupling for Japanese and French vowel /a/ has been performed by a finite element method (FEM) in frequency domain. In this paper, we synthesize vowel /a/ of the 3-D vocal-tract models with the nasal coupling for two Japanese and one French subjects using the FEM in time domain. We examine whether there are any differences between the synthesized vowels of the models with and without the nasal coupling by using an ABX discrimination test.

National audience; Abstract

In the framework of experimental phonetics, our approach to the study of speech production is based on the measurement, the analysis and the modeling of orofacial articulators such as the jaw, the face and the lips, the tongue or the velum. Therefore, we present in this article experimental techniques that allow characterising the shape and movement of speech articulators (static and dynamic MRI, computed tomodensitometry, electromagnetic articulography, video recording). We then describe the linear models of the various organs that we can elaborate from speaker-specific articulatory data. We show that these models, that exhibit a good geometrical resolution, can be controlled from articulatory data with a good temporal resolution and can thus permit the reconstruction of high quality animation of the articulators. These models, that we have integrated in a virtual talking head, can produce augmented audiovisual speech. In this framework, we have assessed the natural tongue reading capabilities of human subjects by means of audiovisual perception tests. We conclude by suggesting a number of other applications of talking heads., Dans le cadre de la phonétique expérimentale, notre approche de l'étude de la production de parole se base sur la mesure, l'analyse, et la modélisation des organes oro-faciaux tels que la mâchoire, le visage et les lèvres, la langue ou le voile du palais. Ainsi, nous présentons dans cet article des techniques expérimentales qui permettent de caractériser la forme et le mouvement des articulateurs de la parole (IRM statique et dynamique, tomodensitographie, articulographie électromagnétique, enregistrements vidéo). Nous décrivons ensuite les modèles linéaires des différents organes dérivés des données articulatoires obtenues sur un locuteur. Nous montrons que ces modèles, qui présentent une bonne résolution géométrique, peuvent être contrôlés à partir de données articulatoires de bonne résolution temporelle et peuvent ainsi permettre de reconstruire des animations d'articulateurs de haute qualité. Ces modèles, que nous avons intégrés dans une tête parlante virtuelle, peuvent servir à produire de la parole audiovisuelle augmentée. Dans ce cadre, nous avons évalué les capacités naturelles de lecture linguale de sujets humains à l'aide de tests perceptifs audiovisuels. Nous concluons par la proposition d'un certain nombre d'autres applications des têtes parlantes.

The goal of this work was the articulatory-acoustic characterization of nasality: the nature of velopharyngeal port movement and associated acoustic characteristics. The building of a 3D linear single-subject articulatory model of the nasal tract from MRI and CT images revealed two degrees of freedom for the movements of the velum and nasopharyngeal wall. The dominant parameter corresponds to a joint vertical oblique movement of the velum and a horizontal movement of the pharyngeal wall, expressing the sphincter effect of the velopharyngeal port. The second parameter corresponds to a smaller movement of the velum, significantly modifying the nasal coupling area. The space covered by the model's movements corresponds precisely to that described by a velum point measured by electromagnetic articulography. Realistic area functions of the nasal tract derived from the model allowed us to determine acoustic transfer functions for seven vowels and the acoustic influence of velar movements.; Ce travail a pour objectif la caractérisation articulatori-acoustique de la nasalité: nature des mouvements du port vélopharyngé, caractéristiques acoustiques liées. La construction d'un modèle articulatoire linéaire 3D monosujet du conduit nasal à partir d'images IRM et CT a fait émerger deux degrés de liberté parmi les mouvements du voile du palais et de la paroi nasopharyngée. Le premier, prédominant, correspond à un mouvement conjoint vertical oblique du voile et horizontal de la paroi pharyngée, traduisant l'effet de sphincter du port vélopharyngé, et le second à un petit mouvement horizontal du voile seul, modifiant sensiblement l'aire de couplage nasal. L'espace des mouvements du modèle décrit exactement celui d'un point du voile obtenu par articulographie électromagnétique. Les fonctions d'aire réalistes du conduit nasal déduites du modèle ont permis de déterminer les fonctions de transfert acoustiques de sept voyelles et l'influence acoustique des mouvements du voile.

International audience; The problem of nasality is complex and has given rise to a large number of studies, from both perception and production points of view. The nasality feature is related to the velum position: lowering the velum, and thus opening the velopharyngeal port, is a simple gesture that induces strong and complex changes in the vocal tract acoustical behaviour. The realisation of nasality involves (1) an articulatory level that deals with the shape of the articulators and their degrees of freedom, and (2) a control level that deals with the coordination of these articulators. The present contribution describes our attempts to characterise at both levels the nasality as realised by one specific subject. The first part is devoted to the development of a 3D articulatory model of the velum that complements the jaw, tongue and lips models already built from MRI data collected on the same subject (Badin et al., 2002). The corpus consisted of a set of artificially sustained phonemes designed as to cover the maximal range of velum positions: the four French nasal vowels and their oral counterparts, and the consonants [p t m n] in three symmetrical contexts [a i u]. Following a method already proven for orofacial articulatory modelling (Badin et al., 2002), the 3D coordinates defining the velum geometry extracted from the MRI data were submitted to decomposition in linear components. Two parameters were found to control the velum, roughly corresponding to vertical and horizontal movements of the uvula, and explaining 74 % of the data variance, with an RMS reconstruction error of 0.13 cm. In addition, a detailed description of the 3D geometry of the nasal and paranasal cavities of the subject was obtained from EBCT scans, and associated with the velum and tongue models to reconstruct area functions. The use of 3D is particularly important, as it appears that the subject's uvula is often in contact with both the back of the tongue and the pharyngeal wall, creating an occlusion in the midsagittal plane, though lateral canals remain open. The influence of tongue upon velum was also studied in detail. The whole model provides finally a link between the oropharyngeal port area and the velum control parameters. The second aspect of the work was the study of the effects of spatial and contextual coarticulation on the velum position in vowels and consonants, and on the associated acoustic outputs. We present an articulatory analysis of velar movements obtained by ElectroMagnetic Articulography for consonants and vowels recorded for the MRI subject uttering the same corpus of VCV sequences. These findings increase our knowledge of the articulatory control of nasality, and open the way to the articulatory synthesis of nasal vowels and consonants. Badin, P., Bailly, G., et al. (2002). Three-dimensional articulatory modeling of tongue, lips and face, based on MRI and video images. J. Phonetics, 30(3), 533-553.

International audience; Volume images of tongue, jaw, velum, nasopharyngeal wall, etc., were acquired by MRI on one French subject uttering a corpus of sustained articulations. Supplementary images of jaw, hard palate, and nasal cavities were acquired by CT. The three-dimensional outlines of these organs are represented by the vertices of triangular surface meshes. Using linear component analysis, the tongue was found to possess five degrees of freedom, including one for jaw movement, and the velum and nasopharyngeal port two degrees of freedom. These parameters can be interpreted in phonetic / biomechanical terms control a linear articulatory model of speech production.

Introduction: Medical simulation, as a component of medical training, may be seen as the creation of a realistic environment with standardized and reproducible scenarios without endangering patients. Simulators enable a level of competency to be obtained before skills of physicians are put into practice[for full text, please go to the a.m. URL], GMDS 2015; 60. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie e.V. (GMDS)