Journal of Phonetics最新文献

The diachronic change by which coarticulatory nasalization increases in VN (vowel-nasal) sequences has been modelled as an earlier alignment of the velum combined with oral gesture weakening of N. The model was tested by comparing American (USE) and Standard Southern British English (BRE) based on the assumption that this diachronic change is more advanced in USE. Real-time MRI data was collected from 16 USE and 27 BRE adult speakers producing monosyllables with coda /Vn, Vnd, Vnz/. For USE, nasalization was greater in V, less in N, and there was greater tongue tip lenition than for BRE. The dialects showed a similar stability of the velum gesture and a trade-off between vowel nasalization and tongue tip lenition. Velum alignment was not earlier in USE. Instead, a closer approximation of the time of the tongue tip peak velocity towards the tongue tip maximum for USE caused a shift in the acoustic boundary within VN towards N, giving the illusion that the velum gesture has an earlier alignment in USE. It is suggested that coda reduction which targets the tongue tip more than the velum is a principal physiological mechanism responsible for the onset of diachronic vowel nasalization.

We provide a phonetic examination of intrusive vowels in Sgi Bara [jil]. These vowels are inserted in predictable places, and their quality (either [i], [ɨ], or [u]) is also predictable, so they are not considered phonemic. We demonstrate that they differ from phonemic vowels in their duration, being shorter; and in their articulation, being more peripheral; but not in their intensity. We then demonstrate how this phonetic understanding of the difference between intrusive and phonemic vowels can be used to answer phonological questions about Sgi Bara. We offer two case studies: phonologically ambiguous sequences of high vowels, and frequent two-word combinations that may be univerbating. The results confirm the existence of a distinction between intrusive and phonemic vowels.

Experiment 1 investigates whether individual differences in sensitivity to acoustic cues in L1 category perception measured by the Visual Analogue Scaling (VAS) task could explain individual variability in L2 phonological contrast learning [research question (RQ1)]. f0 is a solid cue for Korean three-way stop contrasts (i.e., lenis-aspirated stop distinction) but not for English voicing contrasts. Results showed that naïve English learners of Korean with more gradient performance in the VAS task, which was used as a proxy of f0 cue sensitivity in L1, had an advantage in L2 contrast learning. More gradient learners showed more nativelike f0 utilization during and after the High Variability Phonetic Training (HVPT), suggesting the transfer of L1 acoustic cue sensitivity to L2 learning. Experiment 2 examines whether the cue-attention switching training with L1 stimuli provided before HVPT sessions could aid learners by reallocating their attention away from the L2-irrelevant to the L2-relevant acoustic dimension (RQ2). Results demonstrated the effectiveness of the cue-attention switching training with L1 stimuli, especially to learners with less sensitivity to f0 in the VAS task. This study emphasizes the importance of considering individual differences in L2 training and shows the possibility of utilizing the VAS task as a pretraining assessment to predict the acquisition of L2 phonological contrasts and L2 cue-weighting strategies.

Relative to one’s default (casual) speech, clear speech contains acoustic modifications that are often perceptually beneficial. Clear speech encompasses many different styles, yet most work only compares clear and casual speech as a binary. Furthermore, the term “clear speech” is often unclear − despite variation in elicitation instructions across studies (e.g., speak clearly, imagine an L2-listener or someone with hearing loss, etc.), the generic term “clear speech” is used when interpreting results, under the tacit assumption that clear speech is monolithic. The current study examined the acoustics and intelligibility of casual speech and two clear styles (hard-of-hearing-directed and non-native-directed speech). We find: (1) the clear styles are acoustically distinct (non-native-directed speech is slower with lower mean intensity and f0); (2) the clear styles are perceptually distinct (only hard-of-hearing-directed speech enhances intelligibility); (3) no differences in intelligibility benefits are observed between L1 and L2-listeners. These results underscore the importance of considering the intended interlocutor in speaking style elicitation, leading to a discussion about the issues that arise when reference to “clear speech” lacks clarity. It is suggested that to be more clear about clear speech, greater caution should be taken when interpreting results about speaking style variation.

The pitch accent system of Mainstream American English (MAE) is one of the most well-studied phenomena within the Autosegmental-Metrical (AM) approach to intonation. In this work we present an explicit model grounded in dynamical theory that predicts both qualitative phonological and quantitative phonetic generalizations about the MAE system. While the traditional AM account separates a phonological model of the structure of the accents from the F0 algorithm that interprets the phonological specification, we propose a unified dynamical model that encompasses both. The proposed model is introduced incrementally, one dynamical term at a time, to arrive at the minimal model needed to account for observed empirical generalizations, avoiding unnecessary complexity. The quantitative and qualitative properties of the MAE system that inform the dynamical model are based on an analysis of a large database of productions of the four most well-studied pitch accents of American English: three rising accents (H*, L+H*, L*+H) and a low-falling accent (L*). The dynamic model highlights the importance of velocity-based measures of F0, not typically invoked in intonational research, as key to understanding F0 differences among pitch accent categories. Although the focus of this work is on the MAE pitch accent system, suggestions are made for how the unified phonetic-phonological dynamical framework presented can be further developed to account for other pitch-based phenomena in a variety of languages.

This paper investigates the relationship between vowel production and age using speech data from 109 Chinese L1 speakers (61 females and 48 males) covering an age range of 20 to 80 years. Acoustical estimation of vocal tract length (VTL) as well as multiple acoustic metrics are analyzed with generalized additive mixed models (GAMM). The results indicate that: (1) After controlling for VTL, $F_0$ and duration, vowels show a centralization trend with increasing age, with a more significant effect observed in female speakers; (2) VTL does not significantly change with age; (3) The patterns observed in vowel distinctiveness and duration may present evidence contradicting the notion of vowel lengthening as a compensatory mechanism; (4) The patterns of age-related changes in different measurements and different genders are diverse. The U-shaped change patterns are found in the male speakers and the age around 50 may serve as a turning point. Based on these findings, we have explored some possible reasons for inconsistent conclusions in previous studies. The physiological aging phenomena of vowel production and potential compensatory mechanisms on motor control abilities, as well as other possible influencing factors, are also discussed.

Previous studies have examined whether speakers initiate longer utterances with higher F0. Evidence for such effects is mixed and is mostly based on point estimates of F0 at the beginning of the utterance. Moreover, it is unknown whether utterance length can influence F0 control solely at utterance onset or also during the utterance. We conducted a sentence production task to investigate how control of pitch register – F0 ceiling, floor, and span – is influenced by utterance length. Specifically, we test whether speakers adjust register both in relation to an initially planned utterance length – proactive F0 control – and in response to changes in utterance length that occur after response onset – reactive F0 control. Target sentences in the experiment had one, two, or three subject noun phrases, which were cued with visual stimuli. An experimental manipulation was tested in which some visual stimuli were delayed until after participants initiated the utterance. Evidence for both proactive and reactive control of register was observed. Participants adopted a higher register ceiling and broader span in longer utterances. Furthermore, they decreased the amount of ceiling compression upon encountering delayed stimuli. The findings suggest the presence of a mechanism in which speakers continuously estimate the remaining length of the utterance and use that information to adjust pitch register.

Recent research showed selectivity of perceptual learning in speech to linguistic variables and non-linguistic variables. With regard to the latter Keetels et al. (2016) reported that perceptual learning for one spatial location does not fully generalize to another. This spatial selectivity has been suggested to indicate that learning may target non-linguistic representations. We test whether spatial selectivity is a general property of perceptual learning or whether it is related to specific design choices, such as using a single nonword throughout the study. Therefore, we aimed to replicate spatial selectivity with a paradigm that makes use of a larger set of word and nonword stimuli. However, in three experiments, one in-person and two web-based, no effect of spatial selectivity was observed. A Bayesian analysis suggests that the null hypothesis is better supported by the data than the alternative hypothesis based on the previously reported effect size. Repercussions for the debate about pre-lexical representations in speech processing are discussed.

Relatively little research has been conducted on the effect of hearing an unfamiliar native English accent. This paper tests listeners with varying levels of familiarity with the Glaswegian linguistic environment, presenting them with naturalistic minimal pairs such as hut/hurt – produced by speakers raised in Glasgow – in two-alternative-forced-choice tasks. The results of Experiment 1 show a benefit of long-term familiarity in discriminating minimal pairs with derhoticised /r/, a phonetically eroded form of postvocalic /r/ in working class Glaswegian. Native Glaswegian listeners displayed high sensitivity to difference (d’), and low response bias (c) towards hearing either rhotic or non-rhotic words, indicating accurate perception. Unfamiliar listeners were less sensitive to stimulus difference, and were biased towards hearing plain vowels, demonstrating their unfamiliarity with Glaswegian /r/. Non-rhotic English listeners with a moderate level of experience with Glaswegian showed an effect of ‘perceptual hypercorrection’, i.e. over-reporting /r/ presence. Experiment 2 found that, following a short period of exposure, English listeners with very little experience with Glaswegian also started to show hypercorrection, suggesting rapid adaptation to novel phonetic detail. These results may be explained by some general principles underlying exemplar and hybrid theories, and contribute to the ongoing research into the complex nature of Scottish /r/.

This study investigates cross-linguistic influence of a second language (L2) on the first language (L1) perception in two distinct bilingual populations: Korean heritage speakers (n = 30) and long-term immigrants (n = 26) in the USA, compared to Korean-immersed speakers in South Korea (n = 30). By leveraging the differences in language-specific cue primacy in stop consonants between Korean and English, the present study examined L2 (English) influence in participants’ perceptual cue weighting and discrimination of Korean laryngeal categories through a three-alternative forced-choice identification task and a speeded AX discrimination paradigm. The results indicated divergent patterns of cross-linguistic influence for the two bilingual groups. While heritage speakers showed a decreased reliance on the onset f0 cue, suggesting an assimilatory effect of English, long-term immigrants relied more heavily on this cue than Korean-immersed speakers, suggesting dissimilation with English. Furthermore, in discriminating Korean stops based on f0 differences, heritage speakers demonstrated decreased accuracy while long-term immigrants outperformed Korean-immersed speakers. In addition, individual weighting of f0 in the identification task was found to be predictive of discriminatory performance. Overall, the findings underscore the importance of L1 input and experience in determining the nature of cross-linguistic influence in L1 speech perception.