A brief history of articulatory-acoustic vowel representation

International audienceThis paper aims at following the concept of vowel space across history. It shows that even with very poor experimental means, researchers from the 17 th century started to organize the vowel systems along perceptual dimensions, either articulatory, by means of proprioceptive introspection, or auditory. With the development of experimental devices, and the increasing knowledge in acoustic and articulatory theories in the 19 th century, it is shown how the relationship between the two dimensions tended to tighten. At the mid 20 th century, the link between articulatory parameters such as jaw opening, position of the constriction of the tongue, or lip rounding, and the acoustical values of formants was clear. At this period, with the increasing amount of phonological descriptions of the languages of the world, and the power of the computer database analysis allowing extracting universal tendencies, the question of how the vowel systems are organized arose. The paper discusses this important question, focusing on two points: (1) how the auditory constraints shape the positioning of a specific set of vowel within the acoustic space, and (2) how the articulatory constraints shape the maximal extension of the vowel systems, the so-called maximal vowel space (MVS)

Metod maksimalnog opsega vokala u analizi vokala tokom prelingvalne faze

e main problems in the analysis of vowels which occur in prelingual speech phase are centralization of utterance and unknown dimension of vocal tract. Most researches in this eld are based on the analysis of maximal vowel space (MVS) because discrimination of vowels is very di cult in this early period. MVS analysis includes the estimation of vocal tract (VT) physical dimensions. e aim of this research was to estimate and de ne changes in vowel pronunciation during prelingual speech phase. e analysis and voice recording were performed in a two month old child until he turned one. e recording was performed in 42 sessions, on average 4 sessions every month. Sound segments that look like vowel pronunciation were extracted from the recordings and were used for the formant frequencies estimation by PRAAT so ware. e Burg method was used for formant frequency estimation. Research results showed that MVS can be used in diagnostic procedure from a child’s earliest age. MVS analysis is appropriate for a child’s earliest age as a child needs to pronounce individual phonemes, and does not need to respond to speech stimuli. ese results need to be con rmed on a larger sample when extended analysis should de ne criteria for discrimination of typical and atypical formant frequencies.Glavni problemi pri analizi vokala koji se javljaju u prelingvalnoj fazi su centralizacija izgovora i nepoznate dimenzije vokalnog trakta. Većina istraživača u ovoj oblasti bazira analizu na maksimalnom opsegu vokala (MOV) jer je njihova diskriminacija otežana kod dece na najranijem uzrastu. Analiza MOV uključuje estimaciju zičkih dimenzija vokalnog trakta (VT). Cilj istraživanja je da se utvrde i de nišu promene pri izgovoru vokala tokom prelingvalne faze. Snimanje i analiza su urađeni tokom prve godine života (od drugog do dvanaestog meseca). Snimanje je obavljeno u 42 sesije, u proseku 4 sesije u mesecu. Zvučni segmenti koji su ličili na izgovor vokala su izolovani i korišćeni pri estimaciji u PRAAT so*veru. Za estimaciju formantnih frekvencija korišćen je Burgov metod. Rezultati ukazuju da se MOV analiza može koristiti na najranijem uzrastu jer nije neophodno da dete odgovara na dati stimulus. Ovaj rezultat treba potvrditi na većem uzorku, pri čemu bi proširena analiza de nisala i kriterijume za diskriminaciju tipičnih i atipičnih formantnih frekvencija

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

Perceptuo-motor biases in the perceptual organization of the height feature in French vowels

A paraître dans Acta AcusticaInternational audienceThis paper reports on the organization of the perceived vowel space in French. In a previous paper [28], we investigated the implementation of vocal height contrasts along the F1 dimension in French speakers. In this paper, we present results from perceptual identification tests performed by twelve participants who took part in the production experiment reported in the earlier paper. For each subject, stimuli presented in the identification test were synthesized in two different vowel spaces, corresponding to two different vocal tract lengths. The results showed that first, the perceived French vowels belonging to similar height degrees were aligned on stable F1 values, independent of place of articulation and roundedness, as was the case for produced vowels. Second, the produced F1 distances between height degrees correlated with the perceived F1 distances. This suggests that there is a link between perceptual and motor phonemic prototypes in the human brain. The results are discussed using the framework of the Perception for Action Control (PACT) theory, in which speech units are considered to be gestures shaped by perceptual processes

Asymmetry in vowel perception in L1: evidence from articulatory synthesis of an [i]-[e] continuum

aussi disponible sur:http://www.geocities.com/ch_karypidis/docs/conferences/Karypidis_et_alii_AISV2005_en.pdfFor the past 25 years, a debate on whether vowel discrimination is affected by stimulus presentation order has been raised and the role of peripheral vowels in our perception has been under careful examination.In earlier studies, the method used to synthesize a vowel continuum has been by fragmenting, in equidistant points, the F1/F2 Euclidean distance between two prototypes (best exemplars of two different vowel categories). Nonetheless, the resulting sounds were rather unrealistic, inasmuch as some of them were assigned formant-value combinations that cannot be produced by a human vocal tract. Furthermore, the assignment of fixed F3 and F4 values generated a false spectral peak (around 3100 Hz and thus close to that of [i]) which induced the listeners to identify more [i]'s than they should have. Evidence from a recent study on vowel prototypes suggests that [i] has a very narrow perception zone, despite its acoustic stability and peripherality and notwithstanding the absence of a mid-close [e] in the system.Bearing these methodological inconsistencies in mind, we opted to prepare our stimuli using articulatory synthesis. Therefore, we have synthesized a prototypic French [i] (stimulus no. 1, the most extreme) and then modified its parameters (jaw height and tongue position), gradually and in 9 steps, towards a prototypic French [e] (stimulus no. 10, the least extreme). We subsequently submitted the 10-vowel continuum to 34 native French listeners by conducting:a) an identification test in which listeners were requested to identify as [i] or [e] seven repetitions of each stimulus, presented in random order;b) a discrimination test in which listeners were presented with 34 stimulus combinations [18 one-step pairs (9 stimulus combinations, 2 orders) and 16 two-step pairs (8 stimulus combinations, 2 orders)] and were asked whether the two vowels were the same or different. The ISI (Inter-Stimulus Interval) was fixed at 250 ms and every pair was presented five times.Results from the identification test reveal a clear quantal perception of the two categories.The discrimination results demonstrate that: a) discrimination is more difficult when a more extreme (on the F2' dimension) stimulus is presented second and b) discrimination is significantly easier in the 2-step condition, in both orders of presentation

Directional asymmetries reveal a universal bias in adult vowel perception

published online 21 April 2017Research on cross-language vowel perception in both infants and adults has shown that for many vowel contrasts, discrimination is easier when the same pair of vowels is presented in one direction compared to the reverse direction. According to one account, these directional asymmetries reflect a universal bias favoring “focal” vowels (i.e., vowels whose adjacent formants are close in frequency, which concentrates acoustic energy into a narrower spectral region). An alternative, but not mutually exclusive, account is that such effects reflect an experience-dependent bias favoring prototypical instances of native-language vowel categories. To disentangle the effects of focalization and prototypicality, the authors first identified a certain location in phonetic space where vowels were consistently categorized as /u/ by both Canadian-English and Canadian-French listeners, but that nevertheless varied in their stimulus goodness (i.e., the best Canadian-French /u/ exemplars were more focal compared to the best Canadian-English /u/ exemplars). In subsequent AX discrimination tests, both Canadian-English and Canadian-French listeners performed better at discriminating changes from less to more focal /u/’s compared to the reverse, regardless of variation in prototypicality. These findings demonstrate a universal bias favoring vowels with greater formant convergence that operates independently of biases related to language-specific prototype categorization.This research was supported by NSERC Discovery Grant No. 105397 to L.P. and NSERC Discovery Grant No. 312395 to L.M

By

Vowel normalization is a computation that is meant to account for the differences in the absolute direct (physical or psychophysical) representations of qualitatively equivalent vowel productions that arise due to differences in speaker properties such as body size types, age, gender, and other socially interpreted categories that are based on natural variation in vocal tract size and shape. In this dissertation, we address the metaphysical and epistemological aspects of vowel normalization pertaining to spoken language acquisition during early infancy. We begin by reviewing approaches to conceptualizing and modeling the phonetic components of early spoken language acquisition, forming a catalog of phenomena that serves as the basis for our discourse. We then establish the existence of a vowel normalization computation carried out by infants early in their spoken language acquisition, and put forward a conceptual and technical framework for its investigation which focuses attention on the generative nature of the computation. We then situate the acquisition of vowel normalization within a broader developmental framework encompassing a suite of vocal learning phenomena, including language-specific caretaker vocal exchanges

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

One rule, two frequency effects

The low-mid unrounded front vowel /ɛː/ in German (as in Bären) has been subject to change since Old High German. It slowly merged with the high-mid unrounded front vowel /eː/, but a reversal seems to have emerged recently. This paper investigates both historical and current change of the Bären vowel. Historical change is investigated through literature-based research; current change is examined through corpus-based research. This paper takes the approach of studying both grammatical context and frequency of use. The two major insights of this study are (i) that the BÄREN vowel has been subject to change for a long time and is still variable, and (ii) that frequency effects interact with grammar in an unexpected way. This interaction shows us how to proceed with hybrid grammar-lexicon modelling and I advocate a combined model of Optimality Theory and Exemplar Theory to account for this type of grammar-frequency interactions

Considérations ontogénétiques et phylogénétiques concernant l'origine de la parole. Prédiction de la capacité des conduits vocaux de fossiles reconstitués à produire des sons de parole

http://primatologie.revues.org/797National audienceOntogenetic 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)