Labial Coarticulation Research Articles

Effects of the landline telephone filter and linguistic context on speaker-dependent variability in /s/

Previous research has demonstrated that vowel formants situated near the lower limit of the bandwidth show effects of the telephone filter (Künzel 2001; Byrne and Foulkes 2004). In this work, the effects of the landline telephone filter are examined for one consonant, namely fricative /s/. Although this speech sound is expected to show large effects of narrowband telephone filters due to its high-frequency spectral characteristics, previous work on Dutch telephone speech showed that, despite its compromised acoustics, /s/ still contains considerable amounts of speaker information (Smorenburg & Heeren, 2021). Using English data that were simultaneously recorded as broadband and telephone speech, this work shows large effects of the telephone filter on both the acoustics and linear discriminant analysis (LDA) speaker classification. Linguistic effects were only observable in studio recordings and generally did not have an effect on the speaker classification with one exception: when the following context is labial, LDA speaker-classification accuracy was higher, indicating idiosyncrasies in anticipatory labial coarticulation.

The distribution of speaker information in Dutch fricatives /s/ and /x/ from telephone dialogues.

Although previous work has shown that some speech sounds are more speaker-specific than others, not much is known about the speaker information of the same segment in different linguistic contexts. The present study, therefore, investigated whether Dutch fricatives /s/ and /x/ from telephone dialogues contain differential speaker information as a function of syllabic position and labial co-articulation. These linguistic effects, established in earlier work on read broadband speech, were first investigated. Using a corpus of Dutch telephone speech, results showed that the telephone bandwidth captures the expected effects of perseverative and anticipatory labialization for dorsal fricative /x/, for which spectral peaks fall within the telephone band, but not for coronal fricative /s/, for which the spectral peak falls outside the telephone band. Multinomial logistic regression shows that /s/ contains slightly more speaker information than /x/ in telephone speech and that speaker information is distributed across the speech signal in a systematic way; even though differences in classification accuracy were small, codas and tokens with labial neighbors yielded higher scores than onsets and tokens with non-labial neighbors for both /s/ and /x/. These findings indicate that speaker information in the same speech sound is not the same across linguistic contexts.

Diglossia and change from below in Eastern Cham

AbstractDiglossia canonically refers to language situations with unequal attitudes towards a formal ‘H’ variety, connected to writing, and a colloquial ‘L’ variety, connected to everyday speech. This paper claims that variation that arises as a marker of diglossia can become dissociated from it and persist in the L variety, if it is sufficiently orthogonal to the writing system. With a sociolinguistic survey (n = 30), this paper examines five variables that were markers of quasi-diglossia in Eastern Cham in previous decades. Three of the variables continue to be stereotypes or shibboleths of diglossia, while the other two no longer exhibit any correlation with diglossia: the spirantization ofrand the labial coarticulation ofŋ. The latter were changes from below that decoupled from diglossia, because they were sufficiently opaque to Cham script.

The perception of anticipatory labial coarticulation by blind listeners in noise: A comparison with sighted listeners in audio-only, visual-only and audiovisual conditions

This study investigates the time course of the perception of the /i-y/ contrast by French-speaking blind listeners using a gating paradigm. The performances of the blind listeners in discrimination and identification are compared with the range of performances exhibited by sighted perceivers when stimuli are presented auditorily, visually and audiovisually, whether in acoustically non degraded or in noisy conditions. Results provide evidence in favor of partial compensation for visual deprivation in speech perception. Blind listeners outperformed sighted participants in discriminating between auditorily-presented gated stimuli, particularly in noisy conditions. But this small advantage allowed them to compensate only partially for their inability to exploit visual information in order to process coarticulated speech as quickly and efficiently as sighted controls.

Effects of Congenital Visual Deprivation on the Auditory Perception of Anticipatory Labial Coarticulation

Objective: It has been shown previously that congenitally blind francophone adults had higher auditory discrimination scores than sighted adults. It is unclear, however, if, compared to their sighted peers, blind speakers display an increased ability to detect anticipatory acoustic cues. In this paper, this ability is investigated in both speaker groups. Methods: Using the gating paradigm, /izi/ and /izy/ sequences were truncated to include a variable duration of the vowel. The sequences were used as stimuli in an auditory identification test. Seventeen congenitally blind adults (9 females and 8 males) and 17 sighted controls were recruited. Their task was to identify the second vowel of the sequence. Results: Results show that all participants could reliably identify the rounded vowel prior to its acoustic onset, but steeper identification slopes were found for sighted listeners than for blind listeners. Conclusion: The difference in identification slopes likely suggests that sighted speakers display finer abilities to perceptually follow the decreasing values of the frication noise, compared to blind speakers.

An acoustic and articulatory study of anticipatory labial coarticulation

The acoustic and articulatory aspects of anticipatory labial coarticulation were examined. One female native speaker of American English read a list containing ten repetitions of nonsense V1CV2 sequences where V1 was always [i], C was one of [s], [sh], [z], [yog], and V2 was one of [i], [u], or [a]. The movement of upper and lower lip and jaw were recorded using the strain gauge apparatus developed by Barlow and colleagues, and the acoustic signal was also recorded. Short term spectra were taken of the fricative noise at the beginning and at intervals spaced at 0.25, 0.50, and 0.75 of the duration of the fricative. Two spectral peaks were identified at each point. It was predicted that the frequencies of those peaks would be affected by the nature of the following vowel and that the coarse spectral track would show a downward movement when the following vowel was [u]. Neither of these predictions obtained. This result is in agreement with the EMG data of Gelfer et al. [ 2443–2445 (1989)] but not with the acoustic data of, among others. Sereno et al. [ 512–519 (1987)]. Results from a second speaker and from the analysis of the lip movement data will also be presented.

Temporal measures of anticipatory labial coarticulation for the vowel/u/: within- and cross-subject variability.

The timing of upper lip protrusion movements and accompanying acoustic events was examined for multiple repetitions of word pairs such as "lee coot" and "leaked coot" by four speakers of American English. The duration of the intervocalic consonant string was manipulated by using various combinations of /s/, /t/, /k/, /h/, and /#/. Pairwise comparisons were made of consonant string duration (acoustic /i/ offset to acoustic /u/ onset) with durations of: protrusion movement beginning to acoustic /u/ onset, maximum acceleration of the movement to acoustic /u/ onset, and acoustic /u/ onset to movement end. There were some consonant-specific protrusion effects, primarily on the movement beginning event for /s/. Inferences from measures of the maximum acceleration and movement end events for the non-/s/ subset suggested the simultaneous and variable expression of three competing constraints: (1) end the protrusion movement during the voiced part of the /u/; (2) use a preferred movement duration; and (3) begin the /u/-related protrusion movement when permitted by relaxation of the perceptually motivated constraint that the preceding /i/ be unrounded. The subjects differed in the degree of expression of each constraint, but the results generally indicate that anticipatory coarticulation of lip protrusion is influenced both by acoustic-phonetic context dependencies and dynamical properties of movements. Because of the extensive variation in the data and the small number of subjects, these ideas are tentative; additional work is needed to explore them further.

Anticipatory Coarticulation in the Speech of Adults and Young Children

Three experiments investigated anticipatory lingual and labial coarticulation in the [sV] productions of children and adults. Acoustic, perceptual, and video data were used to trace the development of intrasyllabic coarticulation in the speech of adults and children (ages 3, 5, and 8 years). Although children show greater variability in their articulatory patterns than adults, the data do not support claims that young children produce a greater degree of intrasyllabic coarticulation than older children or adults. Rather, the acoustic and video data suggest that young children and adults produce similar patterns of anticipatory coarticulation, and the perceptual data indicate that coarticulatory cues in the speech of 3-year-old children are less perceptible than those of the other age groups.

Anticipatory labial coarticulation in the speech of German-speaking anterior aphasic subjects: Acoustic analyses

Acoustic correlates of anticipatory labial coarticulation were measured in the speech of two anterior aphasic and two normal control speakers, for whom detailed kinematic data had been previously obtained (Katz et al. 1990). German-spcaking adult subjects produced sentences containing target words contrasting in post-consonantal vowel rounding ([gəli:gə]/[gəly:gə] and [gəle:zə]/[gəlø:zə]). Anticipatory labialization was assessed by measuring frequency shift in the F2 peaks of [ə spectra, and in the F2 transitions of [1] spectra. The results showed that patterns of anticipatory labial coarticulation in the aphasic speakers' speech resembled those of the two normal speakers. Implications are drawn for models of speech production, and for methodological issues in coarticulation research.

Acoustic analyses and perceptual data on anticipatory labial coarticulation in adults and children.

The present study investigated anticipatory labial coarticulation in the speech of adults and children. CV syllables, composed of [s], [t], and [d] before [i] and [u], were produced by four adult speakers and eight child speakers aged 3-7 years. Each stimulus was computer edited to include only the aperiodic portion of fricative-vowel and stop-vowel syllables. LPC spectra were then computed for each excised segment. Analyses of the effect of the following vowel on the spectral peak associated with the second formant frequency and on the characteristic spectral prominence for each consonant were performed. Perceptual data were obtained by presenting the aperiodic consonantal segments to subjects who were instructed to identify the following vowel as [i] or [u]. Both the acoustic and the perceptual data show strong coarticulatory effects for the adults and comparable, although less consistent, coarticulation in the speech stimuli of the children. The results are discussed in terms of the articulatory and perceptual aspects of coarticulation in language learning.

Acoustic analyses and perceptual data on anticipatory labial coarticulation in adults and children

The present study investigated anticipatory labial coarticulation in the speech of adults and children. CV syllables, [s], [t], and [d] before [i] and [u], were produced by an adult male speaker and a female child speaker age 3 years 6 months. Each syllable was computer‐edited to include only the noise‐excited portion of fricative‐vowel stimuli and only the aperiodic portion of stop‐vowel stimuli. LPC spectra were computed for each excised segment. Analyses of the effect of the following vowel on the spectral peak associated with the second formant frequency and on the characteristic spectral prominence for each consonant were performed. Perceptual data were obtained by presenting the aperiodic consonantal segments to subjects who were instructed to identify in a forced choice paradigm the following vowel [i] or [u]. Both the acoustic and perceptual data show strong coarticulatory effects for adults and the absence of such coarticulations in the speech stimuli of the child. The results are discussed in terms of the articulatory and perceptual aspects of coarticulation in language learning.

Anticipatory labial coarticulation: experimental, biological, and linguistic variables.

The research reported here represents an attempt to resolve the differences between two views of anticipatory labial coarticulation. One of these views contends that a speaker begins labial movement toward a rounded vowel in direct relation to the amount of time available, while the other view posits an onset of movement that is temporally locked to the rounded vowel. Electromyographic signals were sampled from four muscles associated with labial movement while, simultaneously, movements of the upper lip in the anterior-posterior and vertical dimensions were recorded. Four native speakers of American English and five native speakers of Swedish served as subjects. Results suggested that (1) there are a number of purely biological and experimental variables which can intrude upon research of this type, and (2) there are also language-specific differences in the production of rounded vowels which suggest that Swedish and American English speakers have learned different motor-programming goals. This second observation is discussed in terms of acoustic/perceptual needs of the speakers of a language.

Labial coarticulation in some French VCV sequences measured by electromyographic and cinematographic techniques

The purpose of this study is to know anticipatory and carryover labial coarticulatory effects during the production of certain french vowel‐sibilant‐vowel sequences. These effects are defined on EMG activity correlated with lip gesture estimated from a film. EMG data are attained from orbicularis oris inferior, mentalis, depressor labii inferioris, levator labii superioris alaeque nasi of two subjects through the use of paint‐on electrodes. Three groups of syllables are defined. Not very protruded syllables [∫i, ȝi, ∫e, ȝe] are characterized by an anticipatory and carryover labial coarticulation with activity of mentalis and orbicularis oris inferior corresponding to protrusion, only if preconsonantal vowel is (−lab]. As concern protruded syllables [sy, zy, so, zo] in a [−lab]preconsonantal context, the influence [+lab] of vowel begins during the production of sibilant with mentalis activity and protrusion. In a [+lab]preconsonantal context, mentalis activity and protrusion decrease slightly during the pr...

Effects of consonantal context on vowel lipreading

In this study physical measurements of talkers' lips during production of CVC monosyllables were correlated with perceptual confusions among the utterances during lipreading. Five talkers were videotaped producing a large set of CVC's with /f,v,w,r,p,b,t,d,h,g/ as consonants and /i,ɪ,a,ᴜ,u/ as vowels. Tracings were made from the tape and intelligibility of lipreading was determined by normal and hearing-impaired viewers. It was found that in contexts with minimal labial coarticulation the variance in vowel confusions was almost completely explained by static measurements of lip height and width at the point of maximal vowel constriction. In bilabial, rounded, and labio-dental contexts, however, it was found that (a) overall intelligibility of the vowel was reduced, (b) lip height and width predicted a high percentage of the perceptual confusions among the vowels, but vowel duration and lip trajectory improved the prediction in some cases, and (c) considerable variation existed among talkers and the intelligibility of individual talkers could be predicted by a small set of measurements of the lips during vowel production. [Work supported by Department of Clinical Investigation, WRAMC.]

Temporal aspects of speech production: anticipatory labial coarticulation.

This research attempts to define the temporal extent of anticipatory labial coarticulation and the effect on rounding onset of a stressed nonround vowel temporally prior to the rounded vowel. The results suggest that the onset on the labial rounding gesture is controlled in relation to the temporal extent of the nonlabial duration preceding the rounded vowel and that the onset of activity for the rounded vowel is somehow related to the stress of the preceding nonround vowel. These results argue against the classic articulatory syllable model as well as against a concept of the onset of rounding being temporally locked to the rounded vowel. They can be argued to support a look-ahead or scanning model.

Anticipatory labial coarficulation: Extent and influencing variables

This research is designed to investigate the temporal extent of anticipatory (right‐to‐left) co articulation as well as the variables which may influence it. Previous research in this and in other laboratories has suggested that anticipatory coarticulation in lip rounding extends for as much as six consonants or 600 ms prior to a rounded vowel. Some recent work, however, has suggested a more limited extent of such coarticulation. The present work is an attempt to resolve this issue and thus shed some light on cognitive representation and input units for the motor control processes of speech generation. Additionally a number of variables have been proposed to influence the precise location of the anticipatory boundary of labial coarticulation; for example front versus back tongue position for the rounded vowel, stress of the rounded vowel preceding the consonant string. In the present experiment these and other variables are controlled and their effect on the onset of coarticulation is described.