Coarticulatory Effects Research Articles

Long-Distance Vowel-to-Vowel Coarticulation in Arabic: Influences of Intervening Consonant Pharyngealization and Length.

This study investigates anticipatory vowel-to-vowel coarticulation in Arabic, and seeks to determine the degree to which it is affected by the pharyngealization and length of intervening consonants. Speakers of Egyptian Arabic were recorded saying sentences containing nonsense sequences of the form /baɁabaCV:/, where C was chosen from {/t/, /tˤ/, /t:/, /tˤ:/} and V was a long vowel /i:/, /a:/ or /u:/. Analysis of the first and second formants of the recorded vowels revealed that (a) vowel-to-vowel coarticulatory effects could sometimes extend to a distance of three vowels before the context vowel; (b) the consonant-to-vowel effects associated with pharyngealization were consistently seen at similar distances, while also decreasing in magnitude at greater distances from the triggering consonant; and (c) effects related to intervening consonant length were idiosyncratic, and in particular did not lead to consistent blocking of vowel-to-vowel effects. In contrast, one speaker showed significant vowel-to-vowel effects at all three measured distances that were effectively blocked in the pharyngealized consonant condition.

Acoustic communication by vocal tract modulation

In both human and nonhuman animals, the airway system may serve as an instrument for acoustic communication. Flow-induced tissue vibrations and noise sources generate the acoustic excitation, whereas the configuration of the vocal tract provides a variable resonant filter system that transforms the excitation into a “message.“ This presentation will describe the development of a vocal tract model in which the effects of articulatory movements that produce speech are generated by specifying independent acoustic events along a time axis. These events consist of directional changes in the first three resonance frequencies of an acoustically-neutral airway configuration and are transformed, via acoustic sensitivity functions, into time-varying modulations of the vocal tract shape. The duration of each event may be considerably overlapped in time with other events to produce efficient transmission of information through the effects of coarticulation. The model will be used to demonstrate construction of syllab...

Tongue-Palate Contact Timing during /s/ and /z/ in English

Although numerous studies have investigated supraglottal strategies for signalling voicing in fricatives, there is still no agreement about the precise characteristics of tongue-to-palate contact timing during voiced as opposed to voiceless fricatives. In this study we use electropalatography (EPG) to investigate articulatory and coarticulatory characteristics of tongue-to-palate contact timing during /s/ and /z/ in English. Five typically speaking participants, speakers of Southern British English, produced 500 trochaic words containing the intervocalic alveolar fricatives /s/ or /z/. The time between the start of the frication and the maximum contact at the place of articulation was expressed as a percentage of each fricative's total duration (time to target, TT).This measure was used to analyse articulatory and coarticulatory timing during /s/ and /z/. Data for absolute timing were also presented. The results showed that the time between the start of the frication and the maximum contact point was longer for /s/ than for /z/. This difference was consistent across speakers but was not significant for all of them. The results of the coarticulatory effects showed that the influence of vowel context on TT values for /s/ and /z/ did not differ significantly, but there was a tendency for /z/ to be more resistant to coarticulation effects than /s/.

Recoverability-driven coarticulation: Acoustic evidence from Japanese high vowel devoicing.

High vowel devoicing in Japanese, where /i, u/ in a C1VC2 sequence devoice when both C1 and C2 are voiceless, has been studied extensively, but factors that contribute to the devoiced vowels' likelihood of complete deletion is still debated. This study examines the effects of phonotactic predictability on the deletion of devoiced vowels. Native Tokyo Japanese speakers (N = 22) were recorded in a sound-attenuated booth reading sentences containing lexical stimuli. C1 of the stimuli were /k, ʃ/, after which either high vowel can occur, and /ʧ, ϕ, s, ç/, after which only one of the two occurs. C2 was always a stop. C1 duration and center of gravity (COG), the amplitude weighted mean of frequencies present in a signal, were measured. Duration results show that devoicing lengthens only non-fricatives, while it has either no effect or a shortening effect on fricatives. COG results show that coarticulatory effects of devoiced vowels are evident in /k, ʃ/ but not in /ʧ, ϕ, s, ç/. Devoiced high vowels, therefore, seem to be more likely to delete when the vowel is phonotactically predictable than when it is unpredictable.

Anticipatory coarticulation and the minimal planning unit of speech.

One of the most persistent arguments against the segment as the minimal planning unit is that the seemingly ubiquitous, thus, presumed obligatory, nature of anticipatory coarticulation (AC) effects favors the syllable or a larger unit. By contrast, we present the results of 3 experiments showing that AC is not ubiquitous, but graded and variable based on (a) phonological availability and (b) the specific criterion to initiate articulation adopted by a speaker. We further argue that phonological encoding is parallel. These results point to (a) the segment, and not the syllable, as the minimal planning unit and (b) a flexible planning scope. Implications with respect to the current formulation of AC regarding phonological availability and the minimal unit of speech articulation are discussed. (PsycINFO Database Record

A theory of subfeatural representations: the case of rounding harmony in Laal

This paper introducessubfeatural representationsto capture subphonemic distinctions at work in ‘subphonemic teamwork’. The unusual case of Laal is presented, in which rounding harmony requires two triggers: a round vowel and a labial consonant. The coarticulatory effect of the labial consonant is shown, on the basis of instrumental evidence, to incur a distinctive, but non-contrastive, intermediate level of rounding on the target vowel, analysed as being featurally [−round], but subfeaturally 〚xround〛 (0 <x< 1). 〚xround〛 vowels are shown to form a separate natural class, which can be independently targeted by phonological processes. Subfeatural representations are argued to constitute an advantageous reification of phonetic knowledge, forming a more solid basis for phonetically driven models of phonology. This proposal builds on the insights of previous literature that perceptual representations are needed in phonology, while eschewing the need for direct reference to phonetics.

Effect of Co-Articulation on One Third Octave Spectral Amplitudes of Vowel /I/

Effect of Co-Articulation on One Third Octave Spectral Amplitudes of Vowel /I/

Effects of Two Linguistically Proximal Varieties on the Spectral and Coarticulatory Properties of Fricatives: Evidence from Athenian Greek and Cypriot Greek.

Several studies have explored the acoustic structure of fricatives, yet there has been very little acoustic research on the effects of dialects on the production of fricatives. This article investigates the effects of two linguistically proximal Modern Greek dialects, Athenian Greek and Cypriot Greek on the temporal, spectral, and coarticulatory properties of fricatives and aims to determine the acoustic properties that convey information about these two dialects. Productions of voiced and voiceless labiodental, dental, alveolar, palatal, and velar fricatives were extracted from a speaking task from typically speaking female adult speakers (25 Cypriot Greek and 20 Athenian Greek speakers). Measures were made of spectral properties, using a spectral moments analysis. The formants of the following vowel were measured and second degree polynomials of the formant contours were calculated. The findings showed that Athenian Greek and Cypriot Greek fricatives differ in all spectral properties across all places of articulation. Also, the co-articulatory effects of fricatives on following vowel were different depending on the dialect. Duration, spectral moments, and the starting frequencies of F1, F2, F3, and F4 contributed the most to the classification of dialect. These findings provide a solid evidence base for the manifestation of dialectal information in the acoustic structure of fricatives.

A deep learning approach for generalized speech animation

We introduce a simple and effective deep learning approach to automatically generate natural looking speech animation that synchronizes to input speech. Our approach uses a sliding window predictor that learns arbitrary nonlinear mappings from phoneme label input sequences to mouth movements in a way that accurately captures natural motion and visual coarticulation effects. Our deep learning approach enjoys several attractive properties: it runs in real-time, requires minimal parameter tuning, generalizes well to novel input speech sequences, is easily edited to create stylized and emotional speech, and is compatible with existing animation retargeting approaches. One important focus of our work is to develop an effective approach for speech animation that can be easily integrated into existing production pipelines. We provide a detailed description of our end-to-end approach, including machine learning design decisions. Generalized speech animation results are demonstrated over a wide range of animation clips on a variety of characters and voices, including singing and foreign language input. Our approach can also generate on-demand speech animation in real-time from user speech input.

Asymmetrical patterns of formant variability in English vowels

Previous studies have claimed that lower formants should be weighted more than higher formants in a perceptual model of vowel perception (e.g., Schwartz et al., 1997). Given this formant weighting hypothesis, and if vowels have acoustic targets, vowels should be more variable in higher formant frequencies. Here, we examined within-speaker variability for five English vowels /æ, ʌ, ɔ, ɛ, ɪ/ in various contexts as produced by 32 speakers in the x-ray microbeam database (Westbury, 1994). For variabilities of the first three formants, only /ɔ/ follows this prediction (i.e., variability: F3 > F2 > F1) while /æ/ exhibits the opposite pattern; if we ignore F3 (as being less reliably measured), most vowels conform to the prediction (i.e., variability: F2 > F1), except for /æ/. Although the F2 variability is generally consistent with the perceptual model of vowel perception, it is also consistent with a possibly greater effect of consonant coarticulation (which is extensive here) on F2 relative to F1; this requires more testing. Further, while these results do not fully conform to the prediction made by the hypotheses, coproduction effects arising from the diverse contexts likely interact with the expected tendency. Correlation with observed kinematic variabilities will also be discussed. [Work supported by NIH grant DC-002717.]

Perceptual assimilation of Mandarin Chinese consonants by native Danish listeners

A perceptual assimilation experiment examined the cross-linguistic mapping of Mandarin Chinese initial consonants to Danish consonants. 24 native Danish listeners were auditorily presented with naturally produced CV syllables which consisted of the Mandarin initial consonants [p, ph, t, th, k, kh, x, ts, tsh, s, tɕ, tɕh, ɕ, tʂ, tʂh ʂ, ɻ, w, j] and vowels from the set [a, u, i, y] so that none of the CV syllables violated the permissible combinations of C and V in Mandarin. The Danish listeners identified the initial consonant of the stimuli with phonetically unambiguous Danish orthographic symbols and provided goodness ratings for each match. We found that assimilation patterns for Mandarin consonants differed greatly as a function of the following vowel, suggesting that native expectations regarding coarticulatory effects of V on C importantly affect perceptual assimilation. For example, Mandarin [tɕ, tɕh, ɕ] were assimilated to Danish <dj, tj, sj>, respectively, when followed by [a, y], but to Danish <t, t, s> when followed by [i]. The detailed results allow us to generate precise predictions for the discriminability and thus learnability of Mandarin consonants for native Danish listeners and learners.

Phonetic variability in Moroccan Arabic rhotics

Moroccan Arabic /r/ and its pharyngealized counterpart exhibit a wide range of variability in their pronunciation, with reported articulations ranging from apical trills to uvular fricatives. Using an phonetic dataset elicited from speakers of the dialect of Fès (reported to traditionally have a uvular variant), I assess the distribution and acoustic properties of rhotic variants, including coarticulatory effects. The data present three distinct rhotic articulations: (1) an apical trill or tap, (2) an apical continuant produced together with high-frequency sibilant noise, and (3) a dorsal sonorant or rhotacized vowel similar to English “burred /r/.” Despite claims in the literature, no uvular fricative was observed in the data, and the dorsal sonorant was identified by speakers as the idiosyncratic local pronunciation. Variants (1) and (2) further exhibit devoiced positional variants. Lowered F2 of adjacent vowels and of sonorant portions of the rhotic signal differentiate the pharyngealized phoneme /rʕ/ from its plain counterpart /r/. However, both phonemes were found to exhibit the same range of variation in their primary articulation. Two acoustic properties common to all variants were (a) depression and attenuation of upper formants and (b) the presence of some aperiodic noise above 5 kHz.

Vowel reduction in word-final position by early and late Spanish-English bilinguals.

Vowel reduction is a prominent feature of American English, as well as other stress-timed languages. As a phonological process, vowel reduction neutralizes multiple vowel quality contrasts in unstressed syllables. For bilinguals whose native language is not characterized by large spectral and durational differences between tonic and atonic vowels, systematically reducing unstressed vowels to the central vowel space can be problematic. Failure to maintain this pattern of stressed-unstressed syllables in American English is one key element that contributes to a “foreign accent” in second language speakers. Reduced vowels, or “schwas,” have also been identified as particularly vulnerable to the co-articulatory effects of adjacent consonants. The current study examined the effects of adjacent sounds on the spectral and temporal qualities of schwa in word-final position. Three groups of English-speaking adults were tested: Miami-based monolingual English speakers, early Spanish-English bilinguals, and late Spanish-English bilinguals. Subjects performed a reading task to examine their schwa productions in fluent speech when schwas were preceded by consonants from various points of articulation. Results indicated that monolingual English and late Spanish-English bilingual groups produced targeted vowel qualities for schwa, whereas early Spanish-English bilinguals lacked homogeneity in their vowel productions. This extends prior claims that schwa is targetless for F2 position for native speakers to highly-proficient bilingual speakers. Though spectral qualities lacked homogeneity for early Spanish-English bilinguals, early bilinguals produced schwas with near native-like vowel duration. In contrast, late bilinguals produced schwas with significantly longer durations than English monolinguals or early Spanish-English bilinguals. Our results suggest that the temporal properties of a language are better integrated into second language phonologies than spectral qualities. Finally, we examined the role of nonstructural variables (e.g. linguistic history measures) in predicting native-like vowel duration. These factors included: Age of L2 learning, amount of L1 use, and self-reported bilingual dominance. Our results suggested that different sociolinguistic factors predicted native-like reduced vowel duration than predicted native-like vowel qualities across multiple phonetic environments.

Lingual Articulation and Coarticulation for Catalan Consonants and Vowels: An Ultrasound Study

Background: The study investigates the tongue position and coarticulatory characteristics of a subset of Catalan consonants and vowels using ultrasound. Method: Ultrasound data were recorded and analyzed for the Catalan front lingual consonants /t, d, n, l, ɾ, s, r, ʎ, ɲ, ʃ/ and vowels /i, e, a, o, u/ in symmetrical VCV sequences produced by 5 adult Catalan speakers. Results: Among other aspects, data show more tongue body fronting for palatal consonants and, among dentals and alveolars, for laminals than for apicals; the manner of articulation demands account for considerable tongue body retraction and predorsum lowering during the trill /r/ and for some tongue body retraction during /l/ next to front vowels. Vowel and consonant coarticulation occurs mostly in lingual regions which are not primarily involved in closure or constriction formation. Differences in the relative prominence of the anticipatory and carryover consonant-to-vowel effects in tongue body position were found to hold clearly for /r/ in all vowel contexts and for palatal consonants next to /a, o, u/. Conclusions: Place-dependent and manner-dependent articulatory characteristics for consonants and vowels account for the most relevant coarticulatory effects and may contribute to explain several sound change patterns.

Target-locus scaling for modeling formant transitions in vowel + consonant + vowel utterances.

The coarticulatory effects described by Öhman [J. Acoust. Soc. Am. 39, 151-168 (1966)] imply that consonant loci cannot always be defined by their associated consonantal contexts alone, but, in Swedish vowel + consonant + vowel utterances, they must also depend on their trans-consonantal vowels (TCVs). His discovery is extended here using a model with TCV-dependent consonant loci and with a unique target for each vowel. The model accurately characterizes the vowel-to-consonant and consonant-to-vowel transitions for the /b/ and /d/ contexts from Öhman's second formant-frequency data as families connected by linear-scaling relationships.

Little Words, Big Impact: Determiners Begin to Bootstrap Reference by 12 Months

ABSTRACTWe tested 12- and 18-month-old English-learning infants on a preferential-looking task which contrasted grammatically correct sentences using the determiner “the” vs. three ungrammatical conditions in which “the” was substituted by another English function word, a nonsense word, or omitted. Our design involved strict controls on phonetic composition of function words and co-articulation effects in the stimuli tested, which were absent in previous studies. The results show an overall significant effect of Function Word (FW), with no significant interaction effects between the two age groups. Overall, infants oriented faster to a target image and had more correct first looks at target following grammatical sentences. Tests within age groups show a significant effect of FW in 18-month-olds for both latency and correct first look, documenting a linguistic sensitivity, which persists over our new acoustic variables. In the 12-month-olds there was a significant effect of FW on first look, although no significant effect of FW for latency appeared. However, pairwise comparisons showed a significant difference between grammatical and ungrammatical FWs in latency even at this age. These findings suggest that some prototypical form of sensitivity to determiners in sentence processing and its use in computing noun reference exists already during early developmental stages surrounding the child’s first words. We speculate on potential explanations for developmental changes between 12 and 18 months.

The phonetics–phonology interface: Representations and methodologies ed. by Joaquín Romero and María Riera

Reviewed by: The phonetics–phonology interface: Representations and methodologies ed. by Joaquín Romero and María Riera Felicitas Kleber The phonetics–phonology interface: Representations and methodologies. Ed. by Joaquín Romero and María Riera. Amsterdam: John Benjamins, 2015. Pp. xxi, 288. ISBN 9789027248541. $149 (Hb). This book presents thirteen papers from the 5th Phonetics and Phonology in Iberia (PaPI) conference in June 2011 in Tarragona, Spain. These papers were selected because they ‘showcase… the thematic and methodological richness of the work presented at the 2011 meeting…that goes beyond the Romance realm’ (vii) and because they ‘represent a multifaceted cross section of current work on the phonetics-phonology interface’ (xix). The majority of the papers focus on Romance languages, but many will nonetheless be of interest to phoneticians and laboratory phonologists working on other languages. The volume includes papers from leading experts in the field as well as junior scientists and is intended for experienced researchers. The thirteen papers are organized into four parts and are preceded by the editors’ introduction, which gives a critical overview of the past and current state of research and frames the following chapters in a very detailed and useful way. In particular, the editors highlight how the papers address the book’s ‘goal of deepening our understanding of the phonetics-phonology interface’ (xix) and suggest broader implications that are not always apparent in the individual papers. The first part is on ‘First and second language acquisition’ and opens with a review chapter by Catherine T. Best entitled ‘Devil or angel in the details? Perceiving phonetic variation as information [End Page 247] about phonological structure’. The author reviews earlier research in which variation was typically viewed as noise that needs to be factored out in order to unveil the abstract phonological structure; she then convincingly argues in favor of the role of phonetic variation in the acquisition of phonological structure. Best draws upon growing evidence suggesting that language learners of all ages benefit from variation in production and thus in perception when shaping their first and second language (L2) phonologies. With their study on ‘Effects of Spanish use on the production of Catalan vowels by early Spanish-Catalan bilinguals’, Joan Carles Mora, James L. Keidel, and James E. Flege contribute to two issues in L2 research, namely language dominance and age of bilingualism. They show that production of and exposure to Catalan and Spanish shape the ways in which the Catalan mid-vowel contrasts are maintained or merged—potentially leading to a change. Variation is again mentioned as an important factor but is not addressed directly in the otherwise careful acoustic analysis. In ‘Cues to dialectal discrimination in early infancy: A look at prosodic, rhythmic and segmental properties in utterances from two Catalan dialects’, Marta Ortega-Llebaria and Laura Bosch compare durational (i.e. rhythmic) measures with the distribution of vowels in unstressed syllables, which differs in the two dialects. The aim was to disentangle possible acoustic effects that may have helped five-month-olds in a previous pilot study to discriminate eastern from western Catalan dialects. The findings point to vocalic rather than rhythmic differences. The paper might have made reference to the wealth of literature that is critical of rhythmic measures (as, for example, addressed by Nava and Goldstein in this volume) and that has demonstrated the difficulty of grouping languages (and even more so dialects) according to simple rhythm typologies (e.g. Grabe & Low 2002, Arvaniti 2009). Given that many dialects differ foremost in vocalic features (e.g. English varieties), it is indeed worthwhile to further investigate the extent to which young infants pick up on these cues. In ‘Phonology versus phonetics in loanword adaptations: A reassessment of English vowels in French’, Sharon Peperkamp investigates French listeners’ perception of American English vowels presented within the original context (flanked by labial consonants) or in isolation. The author compares the results to on-line adaptations of French speakers to the same CVC stimuli that were obtained in a previous study. Different responses to spliced (where listeners could not compensate for coarticulatory effects) vs. unspliced vowels (where...

Stressed vowel assimilation to palatal consonants in early Romance

This study is an investigation of the phonetic causes of stressed mid and low vowel raising and diphthongization before single palatal consonants and [jC] sequences in the Early Romance languages, as for example [a] raising in Spanish leche derived from Latin [ˈlakte] ‘milk’. The initial hypothesis put to test is that the chances that vowel assimilation applies should increase with the prominence of the anticipatory consonant-to-vowel effects in tongue dorsum raising and fronting and in the second formant (F2) frequency. In accordance with this prediction, vowel assimilatory processes were found to operate most often before [j] + dentoalveolar sequences and single palatals involving maximal dorsal contact in the case of [a] (and to some extent for [ɛ ɔ] as well), and before single palatals rather than before consonant sequences with [j] in the case of [o]. Moreover, assimilation was more prone to affect [ɛ a ɔ o] than the mid high front vowel [e]. The phonetic account of vowel raising and diphthongization reported in the present study complements other explanatory proposals based on chronological and etymological factors. It also supports the notion that the categorization of segmental coarticulatory effects as assimilatory increase with coarticulation size, and that the diachronic vowel changes in question occurred at a time when palatal consonants were in the process of gaining stability.

Towards a definition of an Egyptian Greek variety

In this paper I study the possibility of an Egyptian Greek variety that — on the phonological level — developed from the 2 nd century CE onward, and which has so far not been defined as an independent language variety. Some preliminary remarks on this have been made, based on the great amount of features present in Greek in Egypt potentially stemming from the contact with Egyptian. Greek texts from Egypt display a substantial amount of nonstandard variation on all linguistic levels. In this paper I investigate the phonological level, concentrating on vowel orthography. Preliminary results of my study indicate Coptic phonological influence in, for example, the allophonic distribution of unstressed vowels, the tendency for consonant-to-vowel coarticulatory effects, and transfer of the Egyptian stress system. Parallel material can be found in the nonstandard usage of Greek loanwords in Coptic, which are used as a comparison for the Greek nonstandard writing forms. In order to be able to differentiate between Coptic impact and Greek internal phonological variation in the analysis of the phonetic variants, Coptic phoneme qualities are compared to the nonstandard renderings of Arabic loanwords in Coptic which display the same phenomena as the Greek ones.

“Identical” vowels in L1 and L2? Criteria and implications for L2 phonetics teaching and learning

Researchers in the field of the teaching and learning of phonetics agree that learners of a foreign/second language (L2) acquire identical vowels by positive transfer from their first language (L1). This statement prompted us to examine whether the French and Czech languages, differing in the size of their vowel inventories, possess any identical vowels that could thus be omitted from French as a Foreign Language (FFL) phonetic curricula intended for Czech learners. The quantification of the vowels’ phonetic similarity is based on the comparison of their (1) phonetic symbols, (2) formant values (F-patterns), and (3) perceptual characteristics. The combined results show that strictly identical vowels between the two languages do not exist, but some French vowels can be defined as highly similar to some Czech vowels. Different coarticulatory effects of vowels produced in isolation and in labial, dental and palato-velar symmetrical environments point to a very strong influence of phonetic contexts on vowel similarity. Indeed, no French vowel is highly similar to any Czech vowel in all of the contexts studied. The findings suggest that phonetic exercises designed for Czech learners should focus on allophonic variations of all French vowels.