Vocal tract growth from birth to adulthood, applications for articulatory studies in infants and biomechanical modeling of the vocal apparatus

International audienceThe growth of the vocal apparatus is far from linear, and reflects several important changes during ontogeny. How are children able to reach acoustic targets in such a context? To counterbalance the nonuniform growth of the vocal tract, adequate motor control of the supra-laryngeal articulators is crucial. Therefore, prior to understand the development of speech production, not only in the acoustic space, but in respect with the articulatory-to-acoustic relationships evolution, it is crucial to study vocal tract morphology

Human vocal tract growth: A longitudinal study of the development of various anatomical structures

International audienceThe growth of the head and neck and its components, including that of the vocal tract, is not homothetic but appears rather as an anamorphosis. The growth of various structures presents a phenomenon of heterochrony. Another important issue in vocal tract growth is sexual dimorphism. It was first claimed that sexual dimorphism appears at puberty, but a recent study has suggested that some prepubertal differences exist. To study these two phenomena, we used longitudinal radiographic data of sixty-eight typical subjects (966 radiographs, taken from 1 month to 25 years) and twelve fetuses (anatomical sections). In this study, we analyzed the growth curves and growth types of the hard and soft palate, the pharyngeal cavity and the estimated length of the whole vocal tract using non-linear mixed-effect models, in order to take advantage of our unique longitudinal dataset. Results indicate that most of the structures follow a neural/somatic growth type, while the pharyngeal cavity follows a more somatic growth type. As concerns sexual dimor-phism, no prepubertal differences were found, suggesting that the sexual dimorphism is likely to begin at puberty. These results have implications for the acoustics of speech production during development and should lead to improvements in vocal tract growth modeling

Effectiveness of ready-to-use therapeutic food compared to a corn/soy-blend-based pre-mix for the treatment of childhood moderate acute malnutrition in Niger.

Standard nutritional treatment of moderate acute malnutrition (MAM) relies on fortified blended flours though their importance to treat this condition is a matter of discussion. With the newly introduced World Health Organization growth standards, more children at an early stage of malnutrition will be treated following the dietary protocols as for severe acute malnutrition, including ready-to-use therapeutic food (RUTF). We compared the effectiveness of RUTF and a corn/soy-blend (CSB)-based pre-mix for the treatment of MAM in the supplementary feeding programmes (SFPs) supported by Médecins Sans Frontières, located in the Zinder region (south of Niger). Children measuring 65 to <110 cm, newly admitted with MAM [weight-for-height (WHM%) between 70% and <80% of the NCHS median] were randomly allocated to receive either RUTF (Plumpy'Nut®, 1000 kcal day(-1)) or a CSB pre-mix (1231 kcal day(-1)). Other interventions were similar in both groups (e.g. weekly family ration and ration at discharge). Children were followed weekly up to recovery (WHM% ≥ 85% for 2 consecutive weeks). In total, 215 children were recruited in the RUTF group and 236 children in the CSB pre-mix group with an overall recovery rate of 79.1 and 64.4%, respectively (p < 0.001). There was no evidence for a difference between death, defaulter and non-responder rates. More transfers to the inpatient Therapeutic Feeding Centre (I-TFC) were observed in the CSB pre-mix group (19.1%) compared to the RUTF group (9.3%) (p = 0.003). The average weight gain up to discharge was 1.08 g kg(-1) day(-1) higher in the RUTF group [95% confidence interval: 0.46-1.70] and the length of stay was 2 weeks shorter in the RUTF group (p < 0.001). For the treatment of childhood MAM in Niger, RUTF resulted in a higher weight gain, a higher recovery rate, a shorter length of stay and a lower transfer rate to the I-TFC compared to a CSB pre-mix. This might have important implications on the efficacy and the quality of SFPs

Ability of reconstituted fossil vocal tracts to produce speech - Phylogenetic and ontogenetic considerations

International audienceWe analyzed 31 skulls from now to 1.5 Ma (millions anni) BP(Before Present) for fossil hominids available at the Musée de l'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: Homo ergaster; 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

Anatomie et croissance du conduit vocal du fœtus à l'enfant de 5 ans

International audienceThe faculty of speech in humans is emerging during the first years of life: from first vocal folds control (around 2-3 month) to first words (around 18-20 month) through canonical babbling (around 7 month), this faculty is developing thanks to the progressive maturation of the neuromuscular control of speech articulators. Prior to understand how this faculty is evolving, and to simulate the acoustic productions during ontogeny, it is crucial to understand the anatomical development of the vocal tract.This study aims at observing the growth of the vocal tract and its constituents, from birth to 5 years. The biometric data presented here allow a better understanding of the evolution of these structures during ontogeny, and will be used in order to build models of newborn's and early child's vocal tracts, to simulate acoustic productions.La faculté de parler se construit durant les premières années de vie : de la phonation sans articulation (aux alentours de 2-3 mois) à la production des premiers mots (12-14 mois), en passant par le babillage (autour de 7 mois). Cette faculté se construit avec la maturation progressive de l'anatomie et grâce à celle du contrôle neuromusculaire des différents articulateurs impliqués dans la production de la parole. Pour comprendre comment se développe cette faculté, et simuler les productions acoustiques au cours de la croissance, il est d'abord indispensable de comprendre l'évolution anatomique de cet instrument. Cette étude se propose de décrire la croissance du conduit vocal et de ses constituants, depuis la période fœtale jusqu'à 5 ans. Les données biométriques présentent l'évolution de ces structures au cours de cette période cruciale. Elles pourront servir à modéliser le conduit vocal du nouveau-né et du jeune enfant, en vue de simuler les productions acoustiques

La croissance du conduit vocal du foetus à l'adulte : une étude longitudinale

International audienceLongitudinal radiographic archives of 68 Caucasian American people followed between 1 month and 25 years were used in order to quantify the growth of the vocal tract. 966 sagittal cephalometric radiographs from the American Association of Orthodontists were used, including a large number of radiographs covering the early years, which is a critical period for speech acquisition. The anatomical sections of 12 fetuses were added to ensure the continuity of data around birth. Eight variables are presented to specify in detail the growth of the vocal tract. These are (1) the oral cavity length; (2) the hard palate length; (3) the soft palate length; (4) the pharyngeal cavity height; (5) the estimated vocal tract length; (6), (7), and (8) the vertical position of each the glottis, the hyoid bone and the third cervical vertebra relative to the occlusal plane, in order to better estimate the vertical evolution of the pharyngeal cavity. Growth curves and growth rates are also computed. Finally, statistical tests are conducted in order to observe the onset of sexual dimorphism. These data are a source of information for the modeling of the vocal tract during ontogenesis, and for the study of articulatory-acoustic relationships during growth.Les archives radiographiques de 68 individus blancs nord-américains suivis longitudinalement entre 1 mois et 25 ans ont été utilisées afin de quantifier la croissance du conduit vocal. 966 téléradiographies sagittales de la tête et du cou provenant de l'Association Américaine des Orthodontistes ont été utilisées, incluant un grand nombre de radiographies couvrant les premières années de vie, période cruciale pour l'acquisition de la parole. Les coupes anatomiques de 12 fœtus ont été ajoutées afin d'assurer une continuité de données pour la période périnatale. Huit variables sont présentées afin de décrire en détail la croissance du conduit vocal : (1) la longueur de la cavité orale, (2) la longueur du palais dur, (3) la longueur du palais mou, (4) la hauteur de la cavité pharyngale, (5) la longueur totale du conduit vocal, (6) la position de la glotte (7) la position de l'os hyoïde et (8) la position de la troisième vertèbre cervicale, relativement au plan occlusal. Les courbes de croissance et les vitesses de croissance sont calculées. Des tests statistiques sont effectués dans le but d'observer l'émergence du dimorphisme sexuel. Ces données sont une source d'information pour modéliser la croissance du conduit vocal et permettent également de mieux comprendre les liens entre anatomie et acoustique au cours de l'ontogenèse

La croissance du conduit vocal du fœtus à l'adulte : une étude longitudinale

International audienceLa croissance du conduit vocal en ontogenèse, loin d'être uniforme, représente une véritable anamorphose. Or, puisque c'est la forme du conduit vocal qui détermine le son produit, la morphogenèse du conduit vocal a d'importantes conséquences acoustiques. Afin de mieux comprendre les relations entre anatomie et acoustique, cette étude propose de quantifier la croissance du conduit vocal du fœtus à l'âge adulte. Les archives radiographiques (966 téléradiographies sagittales de la tête et du cou) de 68 individus blancs nord-américains suivis longitudinalement entre 1 mois et 25 ans ont été utilisées afin de quantifier la croissance du conduit vocal. Les coupes anatomiques de 12 fœtus ont été ajoutées afin d'assurer une continuité de données pour la période périnatale. Huit variables sont présentées afin de décrire en détail la croissance du conduit vocal : (1) la longueur de la cavité orale, (2) la longueur du palais dur, (3) la longueur du palais mou, (4) la hauteur de la cavité pharyngale, (5) la longueur totale du conduit vocal, (6) la position de la glotte (7) la position de l'os hyoïde et (8) la position de la troisième vertèbre cervicale, relativement au plan occlusal. Les courbes de croissance et les vitesses de croissance sont calculées pour chaque variable. Des tests statistiques sont effectués dans le but d'observer l'émergence du dimorphisme sexuel. Nos résultats indiquent que (1) la longueur du conduit vocal double pendant la vie ; (2) la croissance du conduit vocal après la naissance se fait principalement dans la direction verticale ; (3) le profil de croissance des principales structures constitutives du conduit vocal présente deux pics de croissance, le premier durant la période périnatale et le second à l'adolescence (ce second pic étant plus précoce et moins marqué chez les femmes, plus tardif et plus marqué chez les hommes) ; (4) le dimorphisme sexuel apparaît autour de 15 ans et semble être essentiellement dû à une différence de hauteur de la cavité pharyngale, qui présente un second pic de croissance à la puberté marqué uniquement chez les hommes ; (5) la taille du velum est très importante à la naissance en regard de la taille des autres structures. Ces données sont une source d'information pour modéliser la croissance du conduit vocal et permettent également de mieux comprendre les liens entre anatomie et acoustique au cours de l'ontogenèse

Understanding the Biomechanical Properties of Skull Base Tissues Is Essential for the Future of Virtual Reality Endoscopic Sinus and Skull Base Surgery Simulators

International audienc

Intra-household use and acceptability of Ready-to-Use-Supplementary-Foods distributed in Niger between July and December 2010.

Few studies have looked at consumption of Ready-to-Use-Supplementary-Foods (RUSFs) during a nutritional emergency. Here, we describe the use and acceptability of RUSF within households in four districts of the region of Maradi, Niger during large scale preventive distributions with RUSF in 2010 targeted at children 6-35months of age. Our study comprised both quantitative and qualitative components to collect detailed information and to allow in-depth interviews. We performed a cross-sectional survey in 16 villages between two monthly distributions of RUSF (October-November 2010). All households with at least one child who received RUSF were included and a total of 1842 caregivers were interviewed using a structured questionnaire. Focus groups and individual interviews of 128 caregivers were conducted in eight of the selected villages. On average, 24.7% of households reported any sharing of RUSF within the household. Sharing practices outside the household remained rare. Most of the sharing reported occurred among children under 5years of age living in the household. On average, 91% of caregivers in all districts rated the child's appreciation of the products as good or very good. Program planning may need to explicitly accounting for the sharing of products among children under 5 within household

Croissance du conduit vocal de la naissance à l'âge adulte : données morphologiques longitudinales et modélisation articulatoire

National audienceThe growth of the vocal tract is far from linear and is particularly important during the first years of life. How are children able to reach acoustic targets in such a context? To understand the development of speech production, not only in the acoustic space, but with respect to the evolution of articulatory-to-acoustic relationships, it is crucial to study vocal tract morphology. This study aims at proposing specific measurements on the vocal apparatus, not only to study vocal tract growth during ontogeny, but in order to improve the accuracy of articulatory phonetic tools, such as ultrasonography or biomechanical modeling of the vocal tract