Vowel Sequences Research Articles

Pronunciation Patterns and Challenges of the Japanese Long Vowel (Chouon) /ei/ Among Indonesian Students

This study examines the pronunciation patterns of the Japanese vowel sequence /ei/ among 62 students from six universities across six provinces in Indonesia. In Japanese, the vowel sequence /ei/ is commonly neutralized to /e:/. According to Takayama (1992), this neutralization is incomplete in formal or careful speech, where /ei/ is pronounced distinctly as /ei/. Hashimoto (2006) observed that speakers alternate between /ei/ and /e:/, particularly at the ends of sentences. This research explores how Indonesian students, who typically pronounce words according to their written forms, produce the vowel sequence /ei/ in both the initial and final positions of familiar Japanese words. This study was conducted between January to June 2024. Participants were tasked with identifying instances where native Japanese speakers used the long vowel /ei/ in sentences. They then recorded their pronunciations of these words in various positions. The recordings were analyzed using PRAAT software. Results show that native Japanese speakers typically pronounce /ei/ as a long /e:/ with an average duration of 0.173 seconds. In comparison, Indonesian learners pronounced /ei/ in "reizouko" with an average duration of 0.204 seconds and in "yotei" with 0.148 seconds, indicating a tendency for longer pronunciation at the beginning of words. The longest recorded duration was 0.49 seconds, and the shortest was 0.04 seconds, possibly due to hesitation. Furthermore, learners tended to simplify the /ei/ sound, especially at the start or end of sentences. This study highlights the need for targeted pronunciation instruction and additional practice time in Japanese language curricula to address these specific phonetic challenges.

Korean vowel harmony has weak phonotactic support and has limited productivity

Abstract Chong (2017) claims that a derived environment process is productive to the extent that it is supported by phonotactics. The present study tests this claim by comparing variable patterns observed in Korean vowel harmony of suffix alternation with vowel co-occurrence restrictions in the lexicon. A corpus study replicated findings of previous studies that the harmony in suffix alternation is losing productivity, conditioned by the quality of the stem vowel, the number of intervening consonants between the vowels and the stem class. Phonotactic generalisations in vowel sequences matched such tendencies in the alternation in that harmony was feeble in phonotactics and that some of the factors that modulate the harmony in alternation were found to affect the harmony in phonotactics as well. The findings generally support Chong’s claim that lack of phonotactic support for an alternation makes it harder to learn.

Pupil diameter as an indicator of sound pair familiarity after statistically structured auditory sequence

Inspired by recent findings in the visual domain, we investigated whether the stimulus-evoked pupil dilation reflects temporal statistical regularities in sequences of auditory stimuli. We conducted two preregistered pupillometry experiments (experiment 1, n = 30, 21 females; experiment 2, n = 31, 22 females). In both experiments, human participants listened to sequences of spoken vowels in two conditions. In the first condition, the stimuli were presented in a random order and, in the second condition, the same stimuli were presented in a sequence structured in pairs. The second experiment replicated the first experiment with a modified timing and number of stimuli presented and without participants being informed about any sequence structure. The sound-evoked pupil dilation during a subsequent familiarity task indicated that participants learned the auditory vowel pairs of the structured condition. However, pupil diameter during the structured sequence did not differ according to the statistical regularity of the pair structure. This contrasts with similar visual studies, emphasizing the susceptibility of pupil effects during statistically structured sequences to experimental design settings in the auditory domain. In sum, our findings suggest that pupil diameter may serve as an indicator of sound pair familiarity but does not invariably respond to task-irrelevant transition probabilities of auditory sequences.

Comparing accuracy in voice-based assessments of biological speaker traits across speech types

Nonverbal acoustic parameters of the human voice provide cues to a vocaliser’s sex, age, and body size that are relevant in human social and sexual communication, and also increasingly so for computer-based voice recognition and synthesis technologies. While studies have shown some capacity in human listeners to gauge these biological traits from unseen speakers, it remains unknown whether speech complexity improves accuracy. Here, in over 200 vocalisers and 1500 listeners of both sexes, we test whether voice-based assessments of sex, age, height and weight vary from isolated vowels and words, to sequences of vowels and words, to full sentences or paragraphs. We show that while listeners judge sex and especially age more accurately as speech complexity increases, accuracy remains high across speech types, even for a single vowel sound. In contrast, the actual heights and weights of vocalisers explain comparatively less variance in listener’s assessments of body size, which do not vary systematically by speech type. Our results thus show that while more complex speech can improve listeners’ biological assessments, the gain is ecologically small, as listeners already show an impressive capacity to gauge speaker traits from extremely short bouts of standardised speech, likely owing to within-speaker stability in underlying nonverbal vocal parameters such as voice pitch. We discuss the methodological, technological, and social implications of these results.

Anti-hiatus tendencies in Spanish: rate of occurrence and phonetic identification

Abstract Spanish normative grammar considers any two-vowel combination of /e/, /a/, and /o/ as a hiatus, accepting that they can be pronounced as a diphthong in lower basilects and/or informal registers. This article analyzes speeches of educated speakers, performing an acoustic analysis of 60 segmental and suprasegmental features in 493 vowel sequences. Linear mixed-effects models suggest that two-vowel sequences of /e/, /a/, and /o/ are pronounced as diphthongs in 77.27 % of cases; suprasegmental features (especially duration) are the most reliable cues to distinguish a hiatus from a diphthong in Spanish. These results call for a re-examination of diphthong classification in Spanish.

Neural alpha oscillations index context-driven perception of ambiguous vowel sequences

Perception of bistable stimuli is influenced by prior context. In some cases, the interpretation matches with how the preceding stimulus was perceived; in others, it tends to be the opposite of the previous stimulus percept. We measured high-density electroencephalography (EEG) while participants were presented with a sequence of vowels that varied in formant transition, promoting the perception of one or two auditory streams followed by an ambiguous bistable sequence. For the bistable sequence, participants were more likely to report hearing the opposite percept of the one heard immediately before. This auditory contrast effect coincided with changes in alpha power localized in the left angular gyrus and left sensorimotor and right sensorimotor/supramarginal areas. The latter correlated with participants' perception. These results suggest that the contrast effect for a bistable sequence of vowels may be related to neural adaptation in posterior auditory areas, which influences participants' perceptual construal level of ambiguous stimuli.

Utilizing acoustic methods to investigate word-boundary vowel sequences in one Arabic-Spanish contact situation

In the modern world, the globalized nature of both Arabic and Spanish has led to distinct contact situations in different countries. This investigation focuses on word-boundary vowel sequences, which are typically realized as hiatuses or diphthongs in native Spanish speakers. By contrast, native Arabic speakers will not utilize diphthongs across word boundaries, instead preferring to lengthen one vowel or produce a glottal stop (Mohamed 2020).This investigation examines how these distinct strategies are reconciled in the contact situation of Moroccan immigrants to Spain by utilizing acoustic methods to identify and qualify the bilingual approach to word-boundary vowel sequences. This investigation compares monolingual Spanish speakers (n = 3) to two groups of L1 Arabic (Arabic-dominant and Spanish-dominant, n = 7) in Alicante, Spain. Participants completed a language survey, a reading task, and a sociolinguistic interview. All linguistic tasks were recorded and analyzed acoustically on Praat (Boersma & Weenink 2023) utilizing the waveform and spectrogram to identify the strategies utilized to resolve the phonological boundaries. Results from Spanish-dominant bilinguals differ from previous studies in Puerto Rico (Mohamed, 2020), suggesting that this language contact situation differs in Spain and opening up new avenues for study in this area.

Temporal acoustic properties of the sibilant fricative /s/ for the differential diagnosis of dysarthria and apraxia of speech in Spanish speakers

ABSTRACT Dysarthria and Apraxia of Speech (AoS) are motor speech disorders in which neurological lesions differentially affect motor control, possibly leading to noticeable differences in articulation and consequently sound production. Among the sounds requiring greater motor capacity because of its articulatory complexity is the voiceless alveolar sibilant fricative /s/. The aim of this study was to identify acoustic variables able to distinguish between dysarthria and AoS, and between these disorders and normal speech in Spanish speakers. The production of this fricative was acoustically examined in 28 individuals with motor neurological disorders (20 with dysarthria, 8 with AoS) and in 28 neurologically healthy persons. Participants repeated 12 monosyllabic words containing the fricative plus one of the five Spanish vowels. The variables measured were absolute durations of the fricative, vowel, and fricative+vowel sequence, along with the vowel-to-fricative duration ratio. Findings indicate that duration of the fricative can distinguish between controls and speakers with dysarthria, but not between controls and speakers with AoS. Measures related to vowel duration served to distinguish between speakers with dysarthria and speakers with AoS and between each of them and controls. Further, speakers with dysarthria and those with AoS differed from each other and from controls in terms of articulatory variability; speakers with dysarthria showing most variability. In the latter participants, articulatory variability was higher for unrounded segments, vowels and fricatives, while in speakers with AoS this variability was higher for rounded segments. These observations are discussed within a framework of motor control models.

Clusters and series consonants of the Kaur language (phonological analysis)

The phonotactic system is one of the interesting phonological systems to explain because it is the system that regulates the existence, abilities, and inability of phoneme combinations of a language. To that end, this article describes the Kaur language phonotactic system which includes (1) the cluster phonotactic system and (2) the consonant series phonotactic system. The data in this study were sourced from six key informants who were domiciled in Kaur Regency (Bengkulu Province) with the criteria of being between 50-65 years old, native Kaur tribe, never left their native area, mastered Kaur language and culture well, and communicative. Data was collected through interviews and recording devices. Data were analyzed to determine the cluster and consonant series with the help of a speech analyzer. The results showed that in Kaur language (KL) there are 14 clusters (/pl/, /bl/, /gl/, /mp/, /mb/, /nt/, /nd/, /st/, /ɲc/, /ɲɟ/, /ɲcl/, /ŋk/, /ŋg/, /ŋgl/) and 21 series: /mp, mb, nt, nd, ns, ɲc, ɲɟ, ŋk, ŋg, ŋs, ʕb, ʕt, ʕd, ʕc, ʕk, ʕs, sk, st, ʔm, ʔ-ʕ, ʔ-mp/. In KL there is a unique consonant vowel sequence (homorgan consonant series). There are three rules if-then to explain the cluster of KL and five rules if-then to explain the series of KL consonants. KL has a unique phonotactic system so that this study contributes to the development of KL.

Time-frequency analyses of repetition suppression and change detection in children with neurofibromatosis type 1

Children with neurofibromatosis type 1 (NF1) are at increased risk of developing cognitive problems, including attention deficits and learning difficulties. Alterations in brain response to repetition and change have been evidenced in other genetic conditions associated with cognitive dysfunctions. Whether the integrity of these fundamental neural responses is compromised in school-aged children with NF1 is still unknown.In this study, we examined the repetition suppression (RS) and change detection responses in children with NF1 (n = 36) and neurotypical controls (n = 41) aged from 4 to 13 years old, using a simple sequence of vowels. We performed time–frequency analyses to compare spectral power and phase synchronization between groups, in the theta, alpha and beta frequency bands. Correlational analyses were performed between the neural responses and the level of intellectual functioning, as well as with behavioral symptoms of comorbid neurodevelopmental disorders measured through parental questionnaires.Children with NF1 showed preserved RS, but increased spectral power in the change detection response. Correlational analyses performed with measures of change detection revealed a negative association between the alpha-band spectral power and symptoms of inattention and hyperactivity. These findings suggest atypical neural response to change in children with NF1. Further studies should be conducted to clarify the interaction with comorbid neurodevelopmental disorders and the possible role of altered inhibitory mechanisms in this enhanced neural response.

The effect of rhythm on selective listening in multiple-source environments for young and older adults

Understanding continuous speech with competing background sounds is challenging, particularly for older adults. One stimulus property that may aid listeners understanding of to-be-attended (target) material is temporal regularity (rhythm). In the context of speech-in-noise understanding, McAuley and colleagues recently showed a target rhythm effect whereby recognition of target speech was better when natural speech rhythm of a target talker was intact than when it was temporally altered. The current study replicates the target rhythm effect using a synthetic vowel sequence paradigm in young adults (Experiment 1) and then uses this paradigm to investigate potential age-related changes in the effect of rhythm on recognition (Experiment 2). Listeners identified the last three vowels of temporally regular (isochronous) and irregular (anisochronous) synthetic vowel sequences in quiet and with a competing background sequence of vowel-like harmonic tone complexes presented at various tempos. The results replicated the target rhythm effect whereby temporal regularity in the vowel sequences improved identification accuracy of young listeners compared to irregular vowel sequences. The magnitude of the effect was not found to be influenced by background tempo, but faster background tempos led to greater vowel identification accuracy independent of regularity. Older listeners also demonstrated a target rhythm effect but received less benefit from the temporal regularity of the target sequences than did young listeners. This study highlights the importance of rhythm for understanding age-related differences in selective listening in complex environments and provides a novel paradigm for investigating effects of rhythm on perception.

Same vowels but different contrasts: Mandarin listeners’ perception of English /ei/-/iː/ in unfamiliar phonotactic contexts

The study presented here examines how adult L2 listeners’ L1 phonotactics interferes with L2 vowel perception in different consonantal contexts. We examined Mandarin listeners’ perception of the English /ei/-/iː/ vowel contrast in three onset consonantal contexts, /p f w/, which represent different phonotactic scenarios with respect to the permissibility of Mandarin phonology. L1 Mandarin listeners (N = 42) completed a series of three tasks: a categorisation task, a vowel identification task, and an AXB discrimination task. The results show that English /ei/-/iː/ are perceived as highly contrastive in the /p/ context because both /pei/ and /piː/ constitute a licit sequence in Mandarin phonology. However, participants experience substantial /ei/-/iː/ category confusion in the /f/ and /w/ contexts, where Mandarin listeners repair perceptually by modifying the vowel quality in illicit (unattested) consonant–vowel sequences, i.e., */fiː/ → /fei/ and */wiː/ → /wei/. Further exploratory analyses indicate that L2 listeners’ vowel perception in unfamiliar phonotactic contexts is associated with their target language experience, typically indicated by their L2 vocabulary size. The findings thus suggest that the acquisition of novel phonotactic regularities is tied to increased experience with the L2 lexicon.

Vowel Serialization: A Derivation Contextualized Phenomenon in Yorùbá Morphology

The paper argues against the linguistic contextualisation of vowel serialization as basic phenomenon in the appraisal of Yorùbá concatenation morphology. Its findings are based on lexical derivation hypothesis of the lexical morphology theory to be able to account for the phonology and etymology of specified examples of vowel sequence in the language. Primary and secondary data were collected and subjected to analysis. Two sequence of vowel serialization as a morpho-phonological process in the word formation are identified: the VVCV, VCVV and CVV sequence. Vowel serialization frequently occurs consequent on the deletion of the first intervocalic segment and assimilation process between V1 and V2 in Yorùbá VVCV word sequence. Ideophonic words like gbòò, fòò, sàà, wàà and so on also undergo the similar processes. Also, functors such as kì í, má à, and tí ì comprise two seperate syntactic units each which mark two different functional categories in the language. Therefore, they are to be written seperately. Keywords: Vowel sequence, transformation, Yorubá, lexical morphology, syllabic structures

The phonological status of Swedish au and eu: Proposals, evidence, evaluation

AbstractMost modern studies of Swedish phonology take the view that the underlying vowel inventory of Central Standard Swedish comprises nine, rather than seventeen or eighteen, mutually contrasting vowel phonemes. A residual problem of a classic phonological type concerns the borrowed entities, rendered in traditional Swedish orthography as au and eu, whose ‘status in the vowel system is unclear’ (Riad 2014:42). The present paper scrutinizes earlier and current phonological interpretations of these entities, adduces evidence for and against each proposal, and concludes that the case for treating them as phonemic diphthongs /V͡V/, as /VC/-sequences, or as monosyllabic /VV̯/-sequences is weak and that they should in the first place be viewed as underlying heterosyllabic vowel sequences /VV/, subject to a special phonological stipulation valid for a borrowed sub-domain of the lexicon. Typologically, Central Standard Swedish should continue to be subsumed under the category of languages that lack phonological diphthongs.

Ingo’s Register Treadmill

Ingo's Register Treadmill Ingo Titze (bio) VOICE RESEARCH AND TECHNOLOGY A register treadmill was proposed eight years ago as a diagnostic exercise for exposing involuntary register shifts in the D4 to A4 pitch range.1 The basic concept was to create pitch and vowel progressions that would elicit maximum crossings of harmonics with supraglottal resonances (formants) of the vocal tract. It is well known that sudden increases or decreases in harmonic amplitudes in proximity of a resonance can cause a timbral change that can be considered an acoustic registration.2 In particular, strengthening or weakening the second harmonic with the first formant can be responsible for such a register shift. A pentavowel sequence, combined with a pentatonic scale, was proposed such that source frequencies move in opposite direction to resonance frequencies. This produces multiple harmonic-resonance crossovers. This article is a follow-up to expand the treadmill to include a wider pitch range and sex differences in formant frequencies. While allophonic variations of formants F1 and F2 are large across individuals and languages, a smoothed penta-vowel sequence has been chosen here. Each sequence begins with a wide mouth shape and ends with a narrow mouth shape. Formant frequencies for females have been chosen to be 20 % higher than for males. All formant frequencies are listed below for two vowel sequences. High Vowel Sequence [æ] [ɛ] [e] [ɪ] [i] Male F1 670 550 420 350 280 Female F1 860 660 504 420 320 Male F2 1800 1900 2000 2200 2300 Female F2 2160 2280 2400 2640 2760 Low Vowel Sequence [a] [Ɔ] [o] [Ʊ] [u] Male F1 850 500 360 300 300 Female F1 1020 600 431 360 370 Male F2 1610 800 640 610 595 Female F2 1932 960 768 732 714 In the treadmill, F1 is descending while fo is ascending to produce a maximum number of harmonic/formant crossings. Figure 1 shows the graphic display for a D4–A4 up and down pentatonic scale (solid lines), combined with the low vowel formant frequencies (dashed lines). Note that there are [End Page 197] Click for larger view View full resolution Figure 1. Treadmill for the D4–A4 pentatonic scale produced on low vowels; (a) male sequence and (b) female sequence. five crossings on the ascending scale for both males and females. For males, the crossings are: fo crosses F1 near the [o] vowel; 2fo crosses F1 near the [Ɔ] vowel 2fo crosses F2 near the [o] vowel 3fo crosses F2 near the [Ɔ] vowel 4fo crosses F2 near the [Ɔ] vowel. Note the importance of the [Ɔ] and [o] vowels in males in this region of the pitch range. For females, the same five crossings occur, but on slightly more closed-mouth vowels due to higher overall formant frequencies. For example, fo crosses F1 closer to the [Ʊ] vowel than the [o] vowel. Figure 2 shows the treadmill for the high vowel sequence. The pentatonic scale is kept the same, D4–A4. There are now only two major crossings: fo crosses F1 between [e] and [I] in males and between [I] and [i] in females; 2fo crosses F2 between [æ] and [ɛ] in males and between [ɛ] and [e] in females None of the first 4 harmonics cross the second formant F2. Thus, in this region of the pitch range (D4–A4), acoustic registration in high vowels is carried primarily by the first two harmonics. The fifth and higher harmonics are not plotted. They will interact with F2 and higher formants, particularly if fo is raised. Figures 3 and 4 show the treadmills when the pentatonic scale is raised to the G4–D5 range. Usually one progresses in half-steps to this higher level. Most of the high pitch range for males and female belters is then covered. Figure 3 shows the low vowel sequence. The bright [a] vowel is now included in the crossings, but the general picture has not changed much from the A4–D4 scale. Of special...

When consonants resemble vowels: investigating protracted phonological development in Akan

ABSTRACT This paper addresses the phonology of an Akan-speaking child aged 5;3 with Protracted Phonological Development. His phonological system had many strengths, with most consonants accurate at least some of the time and with many long words, but with weaknesses that lead to a very low Whole Word Match. In addition to some difficulty with consonant and vowel sequences (leading to assimilation), there are issues relative to complex consonants that contain vowel features (consonants with secondary articulations, the labiopalatal glide, and /r/) and with syllabic consonants (nasals and /r/) that lead to deletion, epenthesis, and some extensive changes in output. One complex place of articulation (alveolopalatal) is well-established and frequently overgeneralized in the output. We present a non-linear analysis of his speech production and a plan for intervention targeting his difficulties.

Triggering and spreading of lateral tongue posture

Lateral bracing is a tongue posture that is pervasively maintained during speech across languages (Liu et al., in press), released only for a few English sounds ([l] and occasional low vowels; Gick et al., 2017). While bracing is required for many (e.g., coronal) sounds, it is unclear why bracing is maintained during non-lingual sounds (e.g., labial/glottal consonants). Specifically, it is unknown whether bracing is maintained during non-lingual sounds because it is a pervasive default posture for speech (i.e., turned “on” unless actively suppressed, e.g., for /l/) or whether an unbraced posture can be maintained during extended periods. We collected coronal cross-section ultrasound imaging of the dorsal tongue while participants said “hubba-bubba” (a four-syllable sequence of non-lingual consonants and low vowels) in two contexts: surrounded by mandatorily braced sounds (e.g., /s/) versus unbraced sounds (e.g., /l/). Preliminary results show that the lateral tongue stayed in a lowered position throughout “hubba-bubba” when surrounded by unbraced sounds compared to braced sounds. Results suggest the lateral tongue may be held in one of at least two distinct postures whose activation is controlled by “trigger” events. [Work supported by NIH and NSERC.]

Cortical activity evoked by voice pitch changes: A combined fNIRS and EEG study

Functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG) data were simultaneously obtained from normal-hearing listeners presented with continuous natural vowel sequences to study the interrelation of the haemodynamic and electrophysiological cortical responses evoked by voice pitch changes. fNIRS topographies and distributed ERP source reconstructions both indicated additional activity in the right superior temporal cortex if the prosodic contours varied between successive vowels, rather than being the same throughout the sequences. The source-level ERPs furthermore revealed two temporally and spatially separable adaptation processes in superior temporal cortex: Firstly, the early P1 component was bilaterally attenuated when vowels with the same prosodic contours were presented repeatedly, reflecting sensory adaptation. Secondly, the later P2 and sustained potential components were smaller in the right hemisphere during sequences without prosodic changes, which is taken to represent an attention-based adaptation effect. The present results demonstrate the convergence of both methods and demonstrate which ERPs underlie the right-lateralised activity in superior temporal cortex evoked in response to pitch changes that has been observed in many neuroimaging studies.

A direct comparison of voice pitch processing in acoustic and electric hearing

In single-sided deafness patients fitted with a cochlear implant (CI) in the affected ear and preserved normal hearing in the other ear, acoustic and electric hearing can be directly compared without the need for an external control group. Although poor pitch perception is a crucial limitation when listening through CIs, it remains unclear how exactly the cortical processing of pitch information differs between acoustic and electric hearing. Hence, we separately presented both ears of 20 of these patients with vowel sequences in which the pitch contours were either repetitive or variable, while simultaneously recording functional near-infrared spectroscopy (fNIRS) and EEG data. Overall, the results showed smaller and delayed auditory cortex activity in electric hearing, particularly for the P2 event-related potential component, which appears to reflect the processing of voice pitch information. Both the fNIRS data and EEG source reconstructions furthermore showed that vowel sequences with variable pitch contours evoked additional activity in posterior right auditory cortex in electric but not acoustic hearing. This surprising discrepancy demonstrates, firstly, that the acoustic detail transmitted by CIs is sufficient to distinguish between speech sounds that only vary regarding their pitch information. Secondly, the absence of a condition difference when stimulating the normal-hearing ears suggests a saturation of cortical activity levels following unilateral deafness. Taken together, these results provide strong evidence in favour of using CIs in this patient group.

The emergence of interior vowels and heterosyllabic vowel sequences in Ngwi (Bantu B861, DRC)

In this article, we offer a historical account of the development of two phonemic ‘interior’ vowels, [ə] and [ɤ], and heterosyllabic vowel sequences in Ngwi, a virtually undescribed West-Coastal Bantu language spoken in the western part of the Democratic Republic of the Congo. While interior vowels phonologized due to the loss of their conditioning environment, most heterosyllabic vowel sequences come from the fission of an erstwhile palatal on-glide diphthong, itself originating in a long [–high] vowel. This origin is exactly the opposite of what has been reported for other language families such as Romance, where certain heterosyllabic vowel sequences of the *iV type evolved into diphthongs. The Ngwi data also show that phonemic interior vowels exist in languages of the Niger-Congo phylum where they had not been reported before. The historical development of heterosyllabic vowel sequences in Ngwi might have parallels in several other Bantu languages from the wider Congo rainforest area, where phonetic and phonological documentation is still embryonic.