Production Of Stop Consonants Research Articles

베트남인의 한국어 폐쇄음 산출에 대한 한국인의 지각 연구

The purpose of this paper is to investigate the perception patterns of Koreans regarding the production of Korean stop consonants by Vietnamese Korean language learners. For this purpose, an experiment was conducted on Koreans' perception of Vietnamese learners’ production of Korean stop consonants.
 The results of the experiment show that when the presentation sound is located at the beginning of the word, the correct answer rate was ‘/ㅌ/ 89%) > /ㅋ/(88%) > /ㅍ/=/ㅂ/(84%) > /ㄱ/=/ㄸ/(74%) ) > /ㄷ/(72%) > /ㅃ/(65%) > /ㄲ/(61%)', and in the case of word-medial onset consonants, ’/ㅍ/, /ㅋ/(91%) > /ㅌ /(88%) > /ㄷ/(68%) > /ㅂ/(61%) > /ㄸ/(60%) > /ㄲ/(51%) > /ㅃ/(46%) > /ㄱ/(40%)’. Except for the case of /ㄸ/ in word-initial and /ㄱ/ in word-medial, accuracy was found to be high in the order of aspirated consonants > plain consonants > tense consonants for both word-initial and word-medial positions. The percentage of correct responses in the word-initial environment was higher than that in the word-medial environment, and this was revealed more clearly through matrix analysis. In both word-initial and word-medial environments, when the target sound was ‘plain’, it was confused with ‘tense’, when it was ‘tense’ it was confused with ‘aspirated’, and when it was ‘aspirated’ it was confused with ‘plain’. Looking at the correct rate for each following vowel, except for the word-medial plain consonant (/ㅣ/ > /ㅜ/ > /ㅏ/), in all other cases, the correct rate was high in the order of /ㅣ/ > /ㅏ/ > /ㅜ/. This result shows that the correct response rate for the following vowels decreases as the vowels move from the front vowels to the back vowels.

Acoustic Variability of /ptk/ and /bdɡ/ in Spanish: A Pilot Study

Propelled by existing research on stop consonant variability in Spanish, this pilot study provides a preliminary acoustic analysis of stop consonant lenition exhibited by speakers of six different varieties of Spanish in Latin America and Spain to explore the gradient acoustic variability in the production of /ptk/ and /bdɡ/ among speakers of different Spanish varieties. Using the acoustic correlate of relative intensity, this analysis considers the effect of various linguistic factors (phoneme, lexical stress, point of articulation, sonority) as well as the extralinguistic factor of Spanish variety on the production of stop consonants in initial, intervocalic position. Results display a higher degree of weakening among speakers of Peninsular and Insular varieties of Spanish compared with those of Latin-American varieties such as Colombian, Mexican, and Peruvian. These exploratory data support the gradient nature of consonant lenition and provide a baseline for future research on stop consonant variability across the Spanish-speaking world.

Stop Consonant Production in Children with Cleft Palate After Palatoplasty.

: The current study examined stop consonant production in children with cleft lip and/or palate (CP ± L) 2-6 months following palatal surgery. : Prospective comparative study. : Multisite institutional. : Participants included 113 children with repaired CP ± L (mean age = 16 months) who were participating in the multicenter CORNET study. Parents of participants were asked to record approximately two hours of their child's vocalizations/words at home using a Language ENvironmental Analysis (LENATM) recorder. Four ten-minute audio-recorded samples of vocalizations were extracted from the original recording for each participant and analyzed for presence of oral stop consonants. A minimum of 100 vocalizations were required for analysis. : Preliminary findings indicate that at least one oral stop was evident in the consonant inventory for 95 of the 113 children (84%) at the time of their post-surgery 16-month recording, and 80 of these children (71%) were producing two or more different stops. Approximately 50% of the children (57/113) produced the three voiced stops, and eight of the children (7%) were producing all six stop consonants. : The findings of this study suggest that the majority of children with repaired CP ± L from English-speaking homes are producing oral stops within six months following palatal surgery. Similar to same-age children without CL ± P, voiced stops were more frequently evident in the children's inventories than voiceless stops. In contrast to findings of previous reports suggesting place of articulation differences, a somewhat comparable percentage of children in this study produced voiced bilabial, alveolar, and velar stops.

¿Pollo o Bollo? Acquisition of Voicing Contrast by Chinese Learners of L3 Spanish

The study examines cross-linguistic influence (CLI) and voice onset time (VOT) in the production of Spanish stop consonants by native speakers of Mandarin Chinese who have learned English as their second language (L2). Six Chinese nationals studying Spanish in the United States at beginning levels and an advanced-level control were recorded reading words in their L1, L2, and L3. Results indicate a general lack of prevoicing in the speakers’ production of the Spanish voiced stops. At the same time, their Spanish VOT values show great variation, with the majority of speakers having combined CLI from L1 and L2 on their L3 VOT. Results are discussed in relation to individual variation and learning context.

Phonetic feature size in second language acquisition: Examining VOT in voiceless and voiced stops

Featural approaches to second language phonetic acquisition posit that the development of new phonetic norms relies on sub-phonemic features, expressed through a constellation of articulatory gestures and their corresponding acoustic cues, which may be shared across multiple phonemes. Within featural approaches, largely supported by research in speech perception, debate remains as to the fundamental scope or ‘size’ of featural units. The current study examines potential featural relationships between voiceless and voiced stop consonants, as expressed through the voice onset time cue. Native English-speaking learners of Spanish received targeted training on Spanish voiceless stop consonant production through a visual feedback paradigm. Analysis focused on the change in voice onset time, for both voiceless (i.e. trained) and voiced (i.e. non-trained) phonemes, across the pretest, posttest, and delayed posttest. The results demonstrated a significant improvement (i.e. reduction) in voice onset time for voiceless stops, which were subject to the training paradigm. In contrast, there was no significant change in the non-trained voiced stop consonants. These results suggest a limited featural relationship, with independent voice onset time (VOT) cues for voiceless and voices phonemes. Possible underlying mechanisms that limit feature generalization in second language (L2) phonetic production, including gestural considerations and acoustic similarity, are discussed.

Role of Regional Language Background and Speech Styles on the Production of Voice Onset Time (VOT) in English among Indonesian Multilinguals

This paper seeks to contribute to the nature of cross-linguistic transfer in the production of English Voice Onset Time (VOT) by adult multilingual speakers in Indonesia in view of how different regional home languages and speech settings shape the phonetic realizations. Three adult multilinguals participated in this pilot project. They are all learners of English as the third language (L3) at the Department of English of a state university in Malang, Indonesia who acquire different regional home languages – Javanese, Sundanese, and Madurese – as the first language (L1) and speak Indonesian as the second language (L2). The participants’ production of bilabial stop consonants of English /p/ and /b/ were elicited from two different speech settings; a careful speech via text readings (monologue and dialogue) and wordlist reading, and a spontaneous speech through natural conversation among participants. 21 tokens from each participant were then analyzed acoustically in Praat. The findings show that the bilingual speaker with L1 Sundanese consistently produced the shortest VOT values of both /p/ and /b/. The Javanese speaker produced the intermediate lag, whereas the Madurese speaker produced the longest aspiration interval. It is shown that the Sundanese language provides the strongest transfer effect, while Madurese gives the least effect. In light of cross-linguistic transfer, however, the overall VOT productions clearly put forth evidence of L1 phonological transfer. The production of non-native bilabial stop VOTs of English is largely due to the absence of this phonetic property in Javanese and Sundanese while Madurese shows marginal similarities. The findings also demonstrate that speech styles play only a marginal role in determining the production of VOTs that the VOTs of /p/ and /b/ in careful speech is found to be slightly longer than in the spontaneous settings. This study makes an original contribution to the area of phonological acquisition in adult speakers by giving attention to the understudied languages of Indonesia in order to more fully understand the interaction of different language systems in multilingual language acquisition and development.

Revisiting Perception–Production Relationships: Exploring a New Approach to Investigate Perception as a Time‐Varying Predictor

AbstractModels of L2 pronunciation learning have hypothesized that accurate speech perception promotes accurate speech production. This claim can be evaluated longitudinally by examining the extent to which changes in stop consonant perception predict changes in stop consonant production. Taking a time‐sensitive view of the perception–production link, this study used longitudinal data to analyze perception as a time‐varying predictor of production accuracy. Mixed‐effects models were fit to oddity, delayed word repetition, and picture description tasks to examine how participants’ perception and production changed over time. Oddity task perception data were then decomposed into their between‐ and within‐subjects components and integrated into the delayed repetition and picture description production models. Surprisingly, only the between‐subjects predictors reached significance, and the strength of the perception–production link varied across production tasks and target phones. The methods used have implications for future research on perception–production links.

Vowel Onset Point Based Screening of Misarticulated Stops in Cleft Lip and Palate Speech

The presence of velopharyngeal dysfunction, dental occlusion, and mislearned articulation in individuals with cleft lip and palate (CLP) results in the production of misarticulated stop consonants. The present work considers vowel onset points (VOPs) as the anchor points, around which the consonant-vowel (CV) transition regions are segmented to analyze the difference between normal and misarticulated stops. VOPs are located using an epoch-synchronously computed feature called maximum weighted inner product. Spectro-temporal dynamics of CV transitions anchored around VOP are analyzed using two-dimensional discrete cosine transform (2D-DCT) coefficients, where 2D-DCT coefficients are derived from single pole filter (SPF) based time-frequency representation. The SPF-based 2D-DCT coefficients are used to train a support vector machine for the classification of normal and misarticulated stops, where the class of misarticulated stops includes weak, nasalized, palatal, velar, pharyngeal, glottal, and devoicing errors produced by CLP speakers. The performance of the proposed VOP detection algorithm is evaluated on a database containing CV units of normal and misarticulated stops, and the results are compared with the state-of-the-art VOP detection methods. The classification results obtained for the proposed SPF-based 2D-DCT coefficients are compared with the short-time Fourier transform-based 2D-DCT coefficients and Mel-frequency cepstral coefficients. Further, the performance of the proposed system is compared with the hidden Markov model-based goodness of pronunciation approach.

Voice onset time variation in natural southern speech

Sociophonetic research has traditionally emphasized vowels and only recently begun to examine consonants. The emerging literature on consonants has found systematic regional variation in consonant production (Jacewicz et al., 2009; Eddington and Turner, 2017). These studies have focused on present-day speakers producing lab-recorded speech and thus provide little historical or naturalistic insight to consonant variation. One way that the production of stop consonants varies is in voice onset time (VOT). In this study, we utilize the Digital Archive of Southern Speech (DASS) (Kretzschmar et al., 2013), a collection of 64 sociolinguistic interviews recorded between 1968 and 1983, to explore consonant variation in an unscripted historical setting. DASS was force-aligned using the Montreal Forced Aligner (McAuliffe et al., 2017), and the VOT of pre-vocalic, word-initial stop consonants in three-minute audio clips from each speaker was measured using AutoVOT (Keshet et al., 2014). VOT was normalized by dividing duration by speaking rate, and this normalized measurement was included as the dependent variable in a mixed effects model. As expected, stress, voicelessness, and a dorsal place of articulation were significant predictors. Our preliminary analysis reveals significant regional and age differences, adding evidence for speaker-specific variation of VOT as a result of sociophonetic variables.

Prediction of listener perception of place-of-articulation in reduced speech

Previous research on stop consonant production found that less than 60% of the stops sampled from a connected speech corpus contained a clearly defined hold duration followed by a plosive release [Crystal and House, JASA(1988)]. How listeners perceive reduced, voiced stop consonant variants is not well understood. The purpose of the current study was to investigate whether an acoustic cue called a relative formant deflection pattern was capable of predicting listeners’ perceptions of these approximant-like, voiced stop consonants variants. A new methodology motivated by a computational model of speech production was used to extract relative formant deflection patterns from excised VCV segments from a reduced speech database. Participants listened to a total of 56 excised VCV stimuli containing approximant-like, voice stop consonant variants and performed a force choice test (i.e., /b-d-g/). The agreement between the perceptions predicted by the relative formant deflection patterns and listeners’ behavioral performance was compared. The expected relative formant deflection pattern correctly predicted listeners' primary response for percent /b/ and /g/ identifications, but not for listeners’ percent /d/ identifications. The implications of these results on a possible invariant acoustic correlate for listeners’ perceptions of place-of-articulation information will be discussed.

Within-category variation in production of Hindi and English stop consonants

This paper addresses the broad question of how phonological structure affects phonetic production using within-category variation of multiple phonetic cues in Hindi and English stop consonants. The intuitive hypothesis, formalized in Dispersion Theory (Lindblom, 1986) is that languages that have more phonological contrasts along a single phonetic dimension should have relatively less within-category variation along that dimension. Hindi (four stop contrasts per place of articulation) speakers are therefore predicted to exhibit less within-category variation in production relative to English (two contrasts per place) speakers. This was observed in the results of Hauser (2016) who examined VOT variation of voiceless aspirated stops in these languages. The present study builds on those results and examines F0 as a second cue to the voicing contrast. The F0 results do not conform to the prediction that Hindi speakers should exhibit less variation. There was no difference in F0 variation between the Hindi and English speakers, yet there were significant differences in the amount of within-category F0 variation among the individual Hindi speakers (Levene’s Test p < 0.001). It is argued that this is because F0 acts as a secondary cue to the voicing contrast. Speakers can exhibit greater and individualized levels of variability in F0 without adding perceptual confusion because the primary cue (VOT) remains distinct.

Voicing contrast of stop consonant production in the speech of individuals with Parkinson disease ON and OFF dopaminergic medication

ABSTRACTThe aims of this study were to: 1) compare voicing contrast in speakers with Parkinson disease (PD) and healthy controls by comparing the separation of voice onset time (VOT) distributions of voiced and voiceless stop consonants and 2) to determine whether the administration of dopaminergic medication affected VOT separation in speakers with PD. Data from a previous study by Fisher and Goberman (2010) were used to compare the VOT measures obtained from a group of speakers with PD with both ON and OFF medication, and a group of healthy controls. Supplementing the previous findings, the current analysis revealed that individuals with PD exhibited significantly less contrast between voiced and voiceless VOT than that observed in healthy speakers. Medication administration did not affect VOT contrast as no differences in VOT separation were observed between the ON and OFF medication states.

Production of stop consonants in 3-to-6-year-old Mandarin-speaking children

The present study compared the temporal measurements of stop consonants in 29 3-to-6-year-old Mandarin-speaking children and 12 Mandarin-speaking adults. Each participant produced 18 Mandarin disyllabic words which contained six stops /p, pʰ, t, tʰ, k, kʰ/ each followed by three vowels /a, i, u/, respectively. All stop consonants were located at the word-initial position in the first syllable. The temporal measurements of VOT, overall burst duration, average duration per burst, the number of burst and VOT-lag duration were obtained. The results showed that Mandarin-speaking children in this age range produced all six stops, especially aspirated stops, with longer VOT means than the adults. The older children produced even longer VOTs than the younger children, which evidenced the overshooting pattern of VOT values in children. Although adult-like short-lag VOTs for unaspirated stops were achieved in all children, the long-lag VOTs for aspirated stops were widespread in the younger group and gradually developed to a concentrated distribution in the older children. Further examination of the burst and VOT-lag revealed that these children tended to produce shorter average duration per burst and longer VOT-lag than the adults for both unaspirated and aspirated stops. These results indicate that children in this age range may not have developed adult-like laryngeal-oral timing pattern and airflow control for stop production.

Speaker and production characteristics of posterior nasal fricatives

Posterior nasal fricatives (PNF) are unusual articulations produced by children both with and without velopharyngeal (VP) anomalies to replace oral fricatives. PNFs are produced by occluding the oral cavity and forcing airflow through a partially closed VP port to create turbulent noise. Often, extra noises occur due to displacement of mucous and/or tissue flutter. The headset of the nasometer was used to record the separate oral and nasal acoustic signals from 18 children who produced PNFs. They ranged in age from 4 to 15 years, 11 were males, and 11 had some form of cleft palate. Examination of the oral acoustic waveforms revealed that all children produced a stop gesture during intended fricative targets—typically a lingual-alveolar or palatal articulation. Sixteen of the children produced a clear flutter (raspberry-like) noise as evidenced by quasi-periodic components in the nasal spectra. All children used PNFs to replace /s/, 13 (72%) to replace /z/, 12 (67%) to replace /tʃ/, and 6 (33%) to replace /ʃ/ and /dʒ/. Most of the children had known histories of conductive hearing loss. Most of the children with cleft palate had adequate VP closure during stop consonant production. Possible causes of PNFs are discussed.

Infant-directed speech in English and Spanish: Assessments of monolingual and bilingual caregiver VOT

It has been shown that monolingual caregivers exaggerate acoustic speech cues in infant-directed speech (IDS), but less is known about the characteristics of IDS in late second-language (L2) bilingual caregivers. Furthermore, there is inconsistency in the literature regarding voice onset time (VOT) of stop consonants in IDS. The present study explores VOT of English and Spanish stops in English monolingual and Spanish-dominant bilingual caregivers, in infant- versus adult-directed speech registers. Both monolinguals and bilinguals exaggerate VOT in IDS; however, different patterns are noted across consonant type and language context. Also, bilinguals produced English stops with Spanish-like and English-like properties, depending upon their L2-proficiency. The characteristics of late-L2 Spanish–English bilingual IDS may create a complex phonetic environment for infants, which may in turn affect the perception and later production of stop consonants in dual language-learning infants.

Spectral Coefficient Analyses of Word-Initial Stop Consonant Productions Suggest Similar Anticipatory Coarticulation for Stuttering and Nonstuttering Adults.

A longstanding hypothesis about the sensorimotor mechanisms underlying stuttering suggests that stuttered speech dysfluencies result from a lack of coarticulation. Formant-based measures of either the stuttered or fluent speech of children and adults who stutter have generally failed to obtain compelling evidence in support of the hypothesis that these individuals differ in the timing or degree of coarticulation. Here, we used a sensitive acoustic technique-spectral coefficient analyses-that allowed us to compare stuttering and nonstuttering speakers with regard to vowel-dependent anticipatory influences as early as the onset burst of a preceding voiceless stop consonant. Eight adults who stutter and eight matched adults who do not stutter produced C1VC2 words, and the first four spectral coefficients were calculated for one analysis window centered on the burst of C1 and two subsequent windows covering the beginning of the aspiration phase. Findings confirmed that the combined use of four spectral coefficients is an effective method for detecting the anticipatory influence of a vowel on the initial burst of a preceding voiceless stop consonant. However, the observed patterns of anticipatory coarticulation showed no statistically significant differences, or trends toward such differences, between the stuttering and nonstuttering groups. Combining the present results for fluent speech in one given phonetic context with prior findings from both stuttered and fluent speech in a variety of other contexts, we conclude that there is currently no support for the hypothesis that the fluent speech of individuals who stutter is characterized by limited coarticulation.

An acoustically-driven vocal tract model for stop consonant production

The purpose of this study was to further develop a multi-tier model of the vocal tract area function in which the modulations of shape to produce speech are generated by the product of a vowel substrate and a consonant superposition function. The new approach consists of specifying input parameters for a target consonant as a set of directional changes in the resonance frequencies of the vowel substrate. Using calculations of acoustic sensitivity functions, these “resonance deflection patterns” are transformed into time-varying deformations of the vocal tract shape without any direct specification of location or extent of the consonant constriction along the vocal tract. The configuration of the constrictions and expansions that are generated by this process were shown to be physiologically-realistic and produce speech sounds that are easily identifiable as the target consonants. This model is a useful enhancement for area function-based synthesis and can serve as a tool for understanding how the vocal tract is shaped by a talker during speech production.

Inter-generational transmission in a minority language setting: Stop consonant production by Bangladeshi heritage children and adults

Aims and objectives:The purpose of this study was to gain a better understanding of speech development across successive generations of heritage language users, examining how cross-linguistic, developmental and socio-cultural factors affect stop consonant production.Design:To this end, we recorded Sylheti and English stop productions of two sets of Bangladeshi heritage families: (1) first-generation adult migrants from Bangladesh and their (second-generation) UK-born children, and (2) second-generation UK-born adult heritage language users and their (third-generation) UK-born children.Data and analysis:The data were analysed auditorily, using whole-word transcription, and acoustically, examining voice onset time. Comparisons were then made in both languages across the four groups of participants, and cross-linguistically.Findings:The results revealed non-native productions of English stops by the first-generation migrants but largely target-like patterns by the remaining sets of participants. The Sylheti stops exhibited incremental changes across successive generations of speakers, with the third-generation children’s productions showing the greatest influence from English.Originality:This is one of few studies to examine both the host and heritage language in an ethnic minority setting, and the first to demonstrate substantial differences in heritage language accent between age-matched second- and third-generation children. The study shows that current theories of bilingual speech learning do not go far enough in explaining how speech develops in heritage language settings.Implications:These findings have important implications for the maintenance, transmission and long-term survival of heritage languages, and show that investigations need to go beyond second-generation speakers, in particular in communities that do not see a steady influx of new migrants.

Velar–vowel coarticulation in a virtual target model of stop production

Velar–vowel coarticulation in English, resulting in so-called velar fronting in front vowel contexts, was studied using ultrasound imaging of the tongue during /k/ onsets of monosyllabic words with no coda or a labial coda. Ten native English speakers were recorded and analyzed. A variety of coarticulation patterns that often appear to contain small differences in typical closure location for similar vowels was found. An account of the coarticulation pattern is provided using a virtual target model of stop consonant production where there are two /k/ allophones in English, one for front vowels and one for non-front vowels. Small differences in closure location along the palate between productions within each context are the result of the trajectory of movement of the tongue from the vowel to vowel through the virtual target beyond the limit of the palate. The overall pattern is thus seen as a combination of a large planned allophonic difference between consonant closure targets and smaller phonetic differences for each particular vowel quality that are the result of coarticulation.

Acoustic modeling of the perception of place information in incomplete stops

Previous research on stop consonant production found that less than 60% of the stops sampled from a connected speech corpus contained a clearly defined hold duration followed by a plosive release [Crystal & House, JASA 1988]. How listeners perceive the remaining portion of incomplete stop consonants is not well understood. The purpose of the current study was to investigate whether relative formant deflection patterns, a potential model of acoustic invariance proposed by Story and Bunton (2010), is capable of predicting listeners’ perceptions of acoustically continuous, voiced stop consonants lacking a canonical hold duration. Listeners were randomly presented a total of 60 voiced stop-consonant VCV stimuli, each 100 ms in duration, synthesized using a computational model of speech production. Stimuli were created using a continuum of 20 equal step constrictions along the length of the vocal tract in three vowel-to-vowel contexts [see Story & Bunton, JSLHR 2010]. Participants listened to the stimuli and performed a forced choice test (i.e., /b-d-g/). The phonetic boundaries predicted by the relative formant deflection patterns and phonetic boundaries obtained by the forced choice test were compared to determine the ability of the acoustic model to predict participants’ perceptions. The acoustic and perceptual results are reported. [Work supported by NIH R01-DC011275.]