Vowel reduction in conversational speech in French: the role of lexical factors

International audienceIn this study we investigate vowel reduction and the role of some lexical factors in the production of vowels extracted from a corpus of French conversations. Vowel durations and spectral quality are examined with respect to 1. their interaction in the corpus, 2. the position of vowels in words, and 3. word frequency and word category. The analyses are conducted on vowels produced by 16 speakers. Our study provides strong evidence that vowel reduction (decrease in durations and more centralized spectral values) affects most of the vowels in conversational speech. The results show that vowels in final syllables of words were less often reduced while the preceding ones show reduced durations and centralized formant values. Moreover vowels are more reduced in monosyllabic function words than in monosyllabic content words. Nevertheless, we did not find a clear effect of word frequency on vowel durations. Finally, our study shows that vowel reduction depends on several factors related to lexical properties (word category) and to prosodic properties (stress and final lengthening)

About Speech Overlaps: Prosodic Cues Contribution in Predicting a Change of Speaker

International audienceThis paper concerns « non-smooth transitions » in turn-taking exchanges, i.e. overlaps speech phases. In this preliminary study, we aim to determine relevant parameters in predicting a speaker change after the overlap phenomenon, in 6 spontaneous speech dialogs

Quelques cas particuliers de détachement à gauche - ou la prosodie à l'aide de la syntaxe

International audienceThis paper presents a pilot study, which aims at characterizing four types of left-detachment in French. Whereas one of the four constructions is clearly composed of two clauses (a clause being defined as a minimal macro-syntactic unit), it is uncertain whether the other three contain one or two clauses. A bundle of prosodic features are implemented into a statistic model in order to predict the one- or two-clause status of these ambiguous constructions. This quantitative procedure is also a first step to highlight the specific prosodic marking of one- vs. two-clause constructions.Cette étude pilote a pour but de caractériser quatre types de détachement à gauche en français.Alors que l'une des quatre constructions est clairement composée de 2 clauses (une clause étant définie comme une unité macro-syntaxique minimale), pour les trois autres le nombre de clauses, une ou deux , fait débat. Un ensemble de parametres prosodiques est utilisé dans un modèle statistique pour catégoriser le nombre de clauses de ces constructions ambigues. Cette procédure quantitative est aussi une première étape d'analyse du marquage prosodique spécifique des constructions à une clause vs à deux clause

In search of intonational cues to content word beginnings in conversational speech

International audienceWe used an annotated conversational French speech corpus to 1. investigate whether the intonational rises that occur at the beginning of French content words in read speech (APRs) are also present in spontaneous speech and therefore available as cues to word segmentation and lexical access, and 2. test two measures of characterizing intonation patterns using automatically extracted F0 and time values. The two measures tested both proved problematic: they were sensitive to the segmental composition of the critical region. We found no evidence that APRs are reliably present in the corpus as a whole, although we suggest that they may be present in particular types of conversational speech

Phonetic variability as a static/dynamic process in speech communication: a cross linguistic study

This study is a cross-linguistic investigation of qualitative and quantitative variations due to 1/ the structure of vocalic system, 2/ the amount of context within speech message. We hypothesize that phonetic distinctivity of vowels in a language is relative to 1/ the properties of the phonological system, 2/ the amount of informational context. Three languages (Spanish, French and English) were analyzed in three different types of speech (isolated vowels, within words and within texts). Results show 1/ centralization in the three vocalic systems relative to the amount of context, 2/ an increase of vowel dispersion also due to an increase of context information

Aspects phonologique et dynamique de la distinctivité au sein des systèmes vocaliques: une étude inter-langue

Dans ce travail nous explorons différentes causes de la variation phonétique. L'analyse d'un corpus multilingue de plusieurs types de parole nous permet d'observer une distinctivité variable des voyelles de chaque système en fonction du contexte de production. Cette variabilité peut être attribuée 1/ à la spécificité des systèmes vocalique, 2/ à la quantité d'information véhiculée dans le message linguistique

Loudness: continuous spectrum sound versus harmonic spectrum sound

International audienceAn experiment is carried out to examine to what extent the loudness of voiced-unvoiced speech sounds is affected by the harmonic or continuous nature of their spectrum. Stimuli are synthesized by a 10 pole numeric filter simulating the transfer function of a vowel; this filter is excited either by white noise (lowpass filtered at 150 Hz, 6 dB/oct) or by a square wave (Fo=150 Hz). The RMS energy and duration of the stimuli are alike. The subjects perform the loudness equalization task using the adjustment method. The effect prooved to be no significant; consequently no relation was found between the loudness and the specific nature of the spectrum

La voyelle nasale en PB et son appendice nasal : étude acoustique et aérodynamique

International audienceCe travail étudie la variabilité acoustique de la réalisation de la voyelle nasale en portugais brésilien provoqué par le contexte segmental droit. Spécifiquement, il s'avère qu'un murmure nasal perceptible est mesurable seulement quand la voyelle nasale précède une plosive, mais pas avant des fricatives. Selon une hypothèse alternative, il n'y aurait aucune différence entre les gestes nasaux dans les deux contextes. Au moyen de données acoustiques et aérodynamiques (flux d'air nasal et oral), un appendice nasale a été identifiée dans les deux contextes de /p/ et de /f/, qui correspond au geste de fermeture des lèvres et montre un taux élevé de flux d'air nasal. Notre hypothèse alternative est par conséquent soutenue, alors que la différence acoustique est expliquée en termes de chevauchement gestuel

Loudness: continuous spectrum sound versus harmonic spectrum sound

International audienceAn experiment is carried out to examine to what extent the loudness of voiced-unvoiced speech sounds is affected by the harmonic or continuous nature of their spectrum. Stimuli are synthesized by a 10 pole numeric filter simulating the transfer function of a vowel; this filter is excited either by white noise (lowpass filtered at 150 Hz, 6 dB/oct) or by a square wave (Fo=150 Hz). The RMS energy and duration of the stimuli are alike. The subjects perform the loudness equalization task using the adjustment method. The effect prooved to be no significant; consequently no relation was found between the loudness and the specific nature of the spectrum

Backchannels revisited from a multimodal perspective

International audienceIn this study, we analyze the role of several linguistic cues (prosodic units, pitch contours, discourse markers, morphological categories, and gaze direction) in French turn-taking face-to-face interactions. Specifically, we investigate vocal and gestural backchannel signals (BCs) produced by a recipient to show his active listening. We show that some particular pitch contours and discursive markers play a systematic role in inducing both gestural and vocal BCs. Conversely, morphological categories and gestural cues rather play a role for gestural BCs