Acoustic Correlates of Word Stress as A Cue to Accent Strength

Due to the clear interference of their mother tongue prosody, many Czech learners produce their English with a conspicuous foreign accent. The goal of the present study is to investigate the acoustic cues that differentiate stressed and unstressed syllabic nuclei and identify individual details concerning their contribution to the specific sound of Czech English. Speech production of sixteen female non-professional Czech and British speakers was analysed with the sounds segmented on a word and phone level and with both canonical and actual stress positions manually marked. Prior to analyses the strength of the foreign accent was assessed in a perception test. Subsequently, stressed and unstressed vowels were measured with respect to their duration, amplitude, fundamental frequency and spectral slope. Our results show that, in general, Czech speakers use much less acoustic marking of stress than the British subjects. The difference is most prominent in the domains of fundamental frequency and amplitude. The Czech speakers also deviate from the canonical placement of stress, shifting it frequently to the first syllable. On the other hand, they seem to approximate the needed durational difference quite successfully. These outcomes support the concept of language interference since they correspond with the existing linguistic knowledge about Czech and English word stress. The study adds specific details concerning the extent of this interference in four acoustic dimensions

Acoustic-phonetic realisation of Polish syllable prominence: a corpus study.

Malisz Z, Wagner P. Acoustic-phonetic realisation of Polish syllable prominence: a corpus study. In: Gibbon D, Hirst D, Campbell N, eds. Rhythm, melody and harmony in speech. Studies in honour of Wiktor Jassem. Speech and Language Technology. Vol 14/15. Poznań, Poland; 2012: 105-114

Fluency-related Temporal Features and Syllable Prominence as Prosodic Proficiency Predictors for Learners of English with Different Language Backgrounds

Prosodic features are important in achieving intelligibility, comprehensibility, and fluency in a second or foreign language (L2). However, research on the assessment of prosody as part of oral proficiency remains scarce. Moreover, the acoustic analysis of L2 prosody has often focused on fluency-related temporal measures, neglecting language-dependent stress features that can be quantified in terms of syllable prominence. Introducing the evaluation of prominence-related measures can be of use in developing both teaching and assessment of L2 speaking skills. In this study we compare temporal measures and syllable prominence estimates as predictors of prosodic proficiency in non-native speakers of English with respect to the speaker's native language (L1). The predictive power of temporal and prominence measures was evaluated for utterance-sized samples produced by language learners from four different L1 backgrounds: Czech, Slovak, Polish, and Hungarian. Firstly, the speech samples were assessed using the revised Common European Framework of Reference scale for prosodic features. The assessed speech samples were then analyzed to derive articulation rate and three fluency measures. Syllable-level prominence was estimated by a continuous wavelet transform analysis using combinations of F0, energy, and syllable duration. The results show that the temporal measures serve as reliable predictors of prosodic proficiency in the L2, with prominence measures providing a small but significant improvement to prosodic proficiency predictions. The predictive power of the individual measures varies both quantitatively and qualitatively depending on the L1 of the speaker. We conclude that the possible effects of the speaker's L1 on the production of L2 prosody in terms of temporal features as well as syllable prominence deserve more attention in applied research and developing teaching and assessment methods for spoken L2.Peer reviewe

The Acoustic Realization of Prosodic Prominence in Polish: Word-level Stress and Phrase-level Accent

Cwiek A, Wagner P. The Acoustic Realization of Prosodic Prominence in Polish: Word-level Stress and Phrase-level Accent. In: Proceedings of Speech Prosody 2018. Poznan, Poland; 2018: 922-926.The current study addresses the question of how word-level (“stress”) and phrase- or sentence-level prominence (“accent”) is realized in Polish. For this purpose, a production experiment eliciting semi-spontaneous utterances was conducted, closely following the methodological approach introduced in [1]. Our acoustic analyses are based on identical target syllables which are embedded in sentences under conditions that allow to disentangle word-level and phrase-level prominence. The acoustic realizations of these target syllables are then subject to linear mixed-effect models fitted for various acoustic parameters: duration, fundamental frequency maximum, intensity, and spectral balance. The models indicate that prominence marking in Polish is realized acoustically in a stable fashion on phrase-level only. Word stress marking occurs only in cases where a lexically stressed syllable simultaneously realizes a phrase-level accent

Prosody-segment interactions in the acoustics of Polish front vowels

Artykuł ten przedstawia badanie akustyczne, stworzone, by zbadać efekty trzech różnych pozycji prozodycznych na fonetyczną produkcję przednich samogłosek w języku polskim w sekwencjach #CV (czyli samogłoski następującej kolejno po granicy prozodycznej i spółgłoskowym nagłosie) oraz #VC (czyli samogłoski następującej bezpośrednio po granicy prozodycznej). Wyniki eksperymentu sugerują, że jeśli chodzi o F1, język polski wydaje się nie rozróżniać między pozycją początku zdania a początku frazy, podczas gdy pewna liczba różnic została znaleziona między tymi dwoma pozycjami versus pozycją w środku zdania. Różnice nie zostały znalezione, jeśli chodzi o parametr F2 czy długość samogłoski. Nie ma również wyraźnego kontrastu między samogłoskami, które następują bezpośrednio po granicy prozodycznej, a tymi, które od tej granicy dzieli spółgłoska. Wyniki te wskazują na różnice w strukturze prozodycznej języka polskiego w porównaniu z innymi językami, w których znajdujemy bardziej wyraźne efekty.This paper presents an acoustic study devised to investigate the effects of three presumably distinct prosodic position on the phonetic realisation of Polish front vowels in #CV (that is, following a prosodic boundary and a consonantal onset) and #VC sequences (that is, immediately following a prosodic boundary). The results of the experiment suggest that Polish does not seem to distinguish between utterance-initial and phrase-initial positions, with some contrasts present between these two positions and phrase-medial tokens with respect to F1. No effects of position have been found for F2 or vowel duration. There are also no clear differences on the acoustic realisation of vowels depending on whether or not they are adjacent to the prosodic boundary. These results raise questions about the nature of prosodic structure in Polish as compared to other languages which show more robust effects

Communicative functions of rhythm in spoken discourse - the case of radio broadcasting

Time is one of the most precious resources in the audio-visual media. Journalists working in radio broadcasting are particularly subject to time constraints. Their message has to be passed on by the speech signal in a few minutes or seconds without visual support of written text or pictures. Therefore, the message has to be structured in a way that the most important aspects of the information are made prominent and interesting for the audience. On the other hand, journalists have to keep in time and need strategies to orient themselves in time in order to achieve exact timing of their spoken discourse. In this article, I lend support to the notion that the rhythmic structure of speech is one of the major tools for journalists to succeed in this endeavor. First, I review some of the literature on the nature of speech rhythm and its role for speech perception, language acquisition, processing and interaction. Second, the state of the art about what we know about rhythmic prominence in radio broadcasting is given. Finally, the idea will be advanced that speech rhythm, sometimes in conjunction with gesture, improves timing and time estimation in journalists speaking on air. A rich set of literature from different domains is presented in order to identify major questions and pathways for future research on speech rhythm in radio broadcasting.Le temps est une ressource précieuse dans les médias audio-visuels. Les journalistes qui travaillent à la radio sont particulièrement soumis aux contraintes temporelles. Leur message doit être diffusé en quelques minutes ou secondes sans le support visuel d'un texte ou des images. Ainsi, le message doit être structuré de telle façon que les aspects les plus importants seront proéminents dans le discours et intéressent l'audience. D'un autre point de vue, les journalistes ont besoin de bien contrôler le temps qu'ils mettent eux-mêmes pour prononcer leur discours et de s'orienter dans le temps pour ajuster le temps de leur intervention le plus précisément possible. Dans cette contribution, j'examine l'hypothèse que le rythme de la parole fournit les structures nécessaires pour la réussite dans ces défis journalistiques. Dans un premier temps, je présente la littérature sur la nature du rythme de la parole et son rôle dans la perception et le traitement de la parole, l'acquisition de la langue et dans l'interaction. Deuxièmement, je passe en revue les résultats principaux des études concernant la proéminence rythmique dans le phonostyle radiophonique. Finalement, l'hypothèse défendue est que le rythme de la parole, parfois concurremment avec les gestes, conduit à un meilleur timing et une meilleure estimation du temps par les journalistes eux-mêmes quand ils sont à l'antenne. L'article fournira au lecteur un aperçu détaillé et multidisciplinaire de la littérature et identifiera les enjeux et de nouvelles pistes pour la recherche future à propos du rythme de la parole à la radio

An exploration of the rhythm of Malay

In recent years there has been a surge of interest in speech rhythm. However we still lack a clear understanding of the nature of rhythm and rhythmic differences across languages. Various metrics have been proposed as means for measuring rhythm on the phonetic level and making typological comparisons between languages (Ramus et al, 1999; Grabe & Low, 2002; Dellwo, 2006) but the debate is ongoing on the extent to which these metrics capture the rhythmic basis of speech (Arvaniti, 2009; Fletcher, in press). Furthermore, cross linguistic studies of rhythm have covered a relatively small number of languages and research on previously unclassified languages is necessary to fully develop the typology of rhythm. This study examines the rhythmic features of Malay, for which, to date, relatively little work has been carried out on aspects rhythm and timing. The material for the analysis comprised 10 sentences produced by 20 speakers of standard Malay (10 males and 10 females). The recordings were first analysed using rhythm metrics proposed by Ramus et. al (1999) and Grabe & Low (2002). These metrics (∆C, %V, rPVI, nPVI) are based on durational measurements of vocalic and consonantal intervals. The results indicated that Malay clustered with other so-called syllable-timed languages like French and Spanish on the basis of all metrics. However, underlying the overall findings for these metrics there was a large degree of variability in values across speakers and sentences, with some speakers having values in the range typical of stressed-timed languages like English. Further analysis has been carried out in light of Fletcher’s (in press) argument that measurements based on duration do not wholly reflect speech rhythm as there are many other factors that can influence values of consonantal and vocalic intervals, and Arvaniti’s (2009) suggestion that other features of speech should also be considered in description of rhythm to discover what contributes to listeners’ perception of regularity. Spectrographic analysis of the Malay recordings brought to light two parameters that displayed consistency and regularity for all speakers and sentences: the duration of individual vowels and the duration of intervals between intensity minima. This poster presents the results of these investigations and points to connections between the features which seem to be consistently regulated in the timing of Malay connected speech and aspects of Malay phonology. The results are discussed in light of current debate on the descriptions of rhythm

Lexical and postlexical prominence in Tashlhiyt Berber and Moroccan Arabic

Tashlhiyt Berber (Afro-Asiatic, Berber) and Moroccan Arabic (Afro-Asiatic, Semitic), two languages spoken in Morocco, have been in contact for over 1200 years. The influence of Berber languages on the lexicon and the segmental-phonological structure of Moroccan Arabic is well-documented, whereas possible similarities in the prosodic-phonological domain have not yet been addressed in detail. This thesis brings together evidence from production and perception to bear on the question whether Tashlhiyt Berber and Moroccan Arabic also exhibit convergence in the domain of phonological prominence. Experimental results are interpreted as showing that neither language has lexical prominence asymmetries in the form of lexical stress. This lack of stress in Moroccan Arabic is unlike the undisputed presence of lexical stress in most other varieties of Arabic, which in turn suggests that this aspect of the phonology of Moroccan Arabic has resulted from contact with (Tashlhiyt) Berber. A further, theoretical contribution is made with respect to the possible correspondence between lexical and postlexical prominence structure from a typological point of view. One of the tenets of the Autosegmental Metrical approach to intonation analysis holds that prominence-marking intonational events (pitch accents) associate with lexically stressed syllables. Exactly how prominence marking is achieved in languages that lack lexical stress is little-understood, and this thesis' discussion of postlexical prominence in Tashlhiyt Berber and Moroccan Arabic provides new insights that bear on this topic. A first set of production experiments investigates, for both languages, if there are acoustic correlates to what some researchers have considered to be lexically stressed syllables. It is shown that neither language exhibits consistent acoustic enhancement of presumed stressed syllables relative to unstressed syllables. The second set of production experiments reports on the prosodic characteristics of question word interrogatives in both languages. It is shown that question words are the locus of postlexical prominence-marking events that however do not exhibit association to a sub-lexical phonological unit. A final perception experiment serves the goal of showing how native speakers of Tashlhiyt Berber and Moroccan Arabic deal with the encoding of a postlexical prominence contrast that is parasitic on a lexical prominence contrast. This is achieved by means of a 'stress deafness' experiment, the results of which show that speakers of neither language can reliably encode a lexically-specified prominence difference. Results from all three types of experiment thus converge in suggesting that lexical prominence asymmetries are not specified in the phonology of either language