Native American English Research Articles

The role of L1-dialect in L2 production

Abstract This study compared the productions of American English (AE) vowels /i/, /u/, /ɛ/, /ɔ/, /ɪ/, /æ/, /ʊ/, /ʌ/, and /ɑ/ between speakers of two Chinese dialects, the Leshan dialect (LSd) and the Xining dialect (XNd). The participants were native speakers of XNd (n = 120) and LSd (n = 120) with advanced English proficiency. Their vowel productions were compared with those of 22 native AE speakers. The results showed that (1) XNd and LSd participants significantly differed in F1 and/or F2 from AE participants when producing /ɪ/, /æ/, /ʌ/, and /ʊ/ and /ɪ/, /ɑ/, /ɔ/, and /ʌ/, respectively; (2) compared with AE participants, XNd participants had significantly longer durations of /ɪ/, /ʊ/, /ʌ/, /ɛ/, and /æ/, and LSd participants had significantly longer durations of /ɪ/, /ʌ/, and /ɛ/. Overall, the vowels that differed in production from that of native speakers were absent in both the L1 dialects and L1 of participants.

More foreign-accented but more comprehensible: Attrition and amelioration of L1 speech in proficient L2 learners.

There is an increasing interest in cross-linguistic influences of the second language (L2) on the first (L1), but its communicative impact remains to be elucidated. This study investigates how L2 learners' L1 pronunciation is perceived as foreign-accented and (in) comprehensible as a function of their L2 learning experience and proficiency levels. Read speech of 154 L1 Japanese learners of L2 English in the J-AESOP corpus was examined, where approximately one-third of them had lived in English-speaking countries and the rest had never lived outside of Japan. Their L1 speech was rated by another group of native Japanese listeners for accentedness and comprehensibility (from October 25, 2022 to August 20, 2023), while their L2 speech was previously rated by native American English listeners for nativelikeness or proficiency. The speakers' vowel acoustics were also examined. More proficient L2 speakers were perceived as more foreign-accented in their L1, but only if they had lived overseas; their length of residence abroad predicted the degree of perceived accentedness. In contrast, more proficient L2 speakers were consistently perceived as more comprehensible in the L1, regardless of prior overseas experience. Acoustic analyses indicated that perceived accentedness is associated with a clockwise chain shift of all vowel categories in the vowel space. It was also revealed that the dispersion, rather than compactness, of vowel production contributed to perceived comprehensibility, although the degree of L1 vowel dispersion did not predict L2 proficiency. The overall results suggest two main conclusions. First, perceptible L1 foreign accent likely results from L1 disuse rather than L2 interference, thereby L1 pronunciation differs from native norms at a system-wide rather than category-specific level. Second, L2 learning has a positive influence on perceived L1 comprehensibility, rather than individuals with clearer and more comprehensible L1 speech being inherently better L2 learners.

Estimates of speech efficiency in monolingual and bilingual speakers of English.

Introduction The Speech Efficiency Score (SES) serves as an acoustic metric for assessing fluency in conversational speech within the temporal domain. This study leverages SES to investigate conversational speech efficiency among native speakers of American English (AE) compared to speakers of Mandarin-accented English (MAE). Methods SES, speaking rate, articulation rate, and vocabulary diversity were measured and compared between two groups: native AE speakers and MAE speakers. The study utilized conversational speech samples collected from both groups to analyze these metrics. Results Findings indicate a disparity in speaking rate and articulation rate between the AE and MAE groups, with the AE group exhibiting significantly faster speech. However, no significant differences were observed in SES and vocabulary diversity between the two groups. Conclusion The results are discussed in the context of the interplay between speaking rate, speech fluency, and vocabulary diversity. These findings shed light on the maintenance of speech efficiency among bilingual speakers, suggesting that despite differences in speaking rate and articulation rate, SES and vocabulary diversity remain comparable between native AE speakers and MAE speakers. .

Exploring auditory recognition: Native Japanese listeners' perception of frequent and infrequent English words in noise with varied phonological neighborhood densities

Native Japanese listeners identified English words embedded in noise (SNR + 6dB) produced by native American English and Japanese speakers. The identical word list used in our previous study (Nozawa and Wayland 2023) was employed. Listeners responded by typing the words they heard. The findings revealed no discernible impacts of phonological neighborhood density, possibly due to the small vocabulary size limiting competition from other words. However, frequent words exhibited greater precision in recognition compared to infrequent words. Despite the introduction of noise, the overall accuracy of responses did not experience a substantial impact. Nevertheless, specific words like “class” and “club,” initially nearly perfect in accuracy without noise, dropped to 0% accuracy. Most errors included phoneme substitution rather than phoneme addition or deletion, and in / CVC/ words, the onset consonant was identified substantially better than the vowel and the coda consonant. Initial consonant clusters, such as /br/, / kl/, and /pl/, were frequently perceived as /l/ or /r/, leading to the initial stops or fricatives being missed. Errors encompassed the substitution of phonemes with others that are not typically perceptually assimilated into the same native language (L1) categories, which would not be revealed through predefined multiple-choice identification or discrimination tasks.

Cross-cultural adaptation of the Iranian Voice Quality of Life Profile into Brazilian Portuguese.

To cross-culturally adapt the Voice Quality of Life Profile (IVQLP) into Brazilian Portuguese (BP). The cross-cultural adaptation process was performed in five stages: translation of the IVQLP into BP by three native BP experts fluent in American English; preparation of a consensus version; back-translation by a native American English expert fluent in BP; analysis by a committee of five experts and preparation of the final version of the instrument in BP, which was named IVQLP-Br; and pre-testing. The IVQLP-Br aims to assess the impacts of the voice more comprehensively, encompassing various areas of an individual's life. It has 43 items and a five-level response key. For the pre-test, the alternative "not applicable" was added as a response option. Thirty-six adults with self-reported risk of dysphonia participated in the pre-test. In the translation stage, ten items were modified, and during the back-translation, 15 items required adjustments. No questions required reformulation after the application of the IVQLP-Br in the target population, because the option "not applicable" appeared in 12 responses without statistical significance. The version of the IVQLP translated into BP, named the IVQLP-Br, exhibited cross-cultural equivalence and was administrable for a more detailed analysis of the impact of the voice in different domains of an individual's life. After validation, the IVQLP-Br will be able to contribute both to clinical practice and to research with BP speakers.

Acoustic characteristics of non-native Lombard speech in the DELNN corpus

Lombard speech, speech produced in noise, has been extensively studied in native speakers, while non-native Lombard speech research is limited. This article presents the first corpus of non-native Lombard speech, the Dutch English Lombard Native Non-Native corpus, which includes plain and Lombard read speech from native American-English, non-native English (native Dutch), and native Dutch women. The location of contrastive focus is systematically varied in the sentences. We investigated how intensity, spectral center of gravity, word duration, and VOT varies in the corpus as a function of plain versus Lombard speech and whether it is modulated by the speaker’s nativeness and of the language. We did not find differences in how the native and non-native English speakers adapted their English speech in noise, indicating that the Dutch non-native speakers produced Lombard speech similarly to the native English. The comparison of the native Dutch and non-native English sentences produced by the same participants nevertheless suggests that, for all acoustic measurements except word duration, the Dutch speakers adapted their Lombard speech differently in native Dutch than in non-native English. Combined, this would indicate that, when speaking English, Dutch speakers adapt their way of speaking in noise to the way native English speakers do.

Is secondary stress phonetically real for second-language learners? Evidence from Japanese-accented English

Speakers of a non-stress language such as Japanese often have difficulty producing lexical stress distinctions in languages such as English. Distinguishing primary-stressed versus unstressed syllables may be difficult, but distinctions involving secondary stress may be even more challenging. Some studies report that Japanese learners of English (JE) do not distinguish secondary-stressed and unstressed syllables in terms of vowel duration and quality whereas native American English speakers (AE) do. However, the data are limited and inconclusive. To resolve this issue, the present study asked AE and two groups of JE differing in English proficiency to produce 83 English words that exhibit stress shift, e.g., phótogràph-phòtográphic-photógraphy and conducted acoustic analysis of vowels in corresponding positions, which have the same consonantal context but differ in stress level. Preliminary results indicate that JE frequently produce devoiced vowels in unstressed syllables, particularly in phonetic environments similar to where devoicing occurs in Japanese. Devoicing, however, does not seem to occur in secondary-stressed syllables, suggesting that JE might distinguish secondary-stressed and unstressed syllables with respect to devoicing. Results from duration and formant analysis will also be reported and discussed in relation to theories of native-language influences on second-language speech learning. [Work supported by JSPS.]

A comparative study of English vowel shifts and vowel space area among Korean Americans in three dialect regions

AbstractRecent sociophonetic research has focused on the ways in which race and ethnicity influence language as well as how language is used to construct racial and ethnic identity. Comparisons of the speech of members of one ethnic group across different regions are still uncommon. In this study, fifty-one native American English speakers of Korean descent, hailing from three different dialect areas of the United States (Los Angeles County and Orange County, California; Harris County, Texas; and Gwinnett County, Georgia), were recorded speaking English in casual interviews. Their speech was analyzed for characteristics of local sound patterns in each region, including the Short Front Vowel Shift (California Vowel Shift) and the Southern Vowel Shift, as well as overall Vowel Space Area. All three groups showed evidence of the Short Front Vowel Shift, and none demonstrated the Southern Vowel Shift. The Californian speakers had the smallest vowel spaces, while the Georgian speakers had the largest. We relate these findings to the ways Korean Americans in Texas and California understand their ethnic identity vis-à-vis a kind of metropolitan or urban speech style in a highly multicultural environment, while, in comparison, Korean Americans in Georgia may use vowel space to highlight their orientation toward or away from local mainstream (white) cultural identity.

Clear speech improves word segmentation in quiet and in noise: Evidence from visual-world eye-tracking

Listener-oriented hyperarticulated clear speech facilitates linguistic processing and cognitive functioning associated with speech perception under various listening conditions. Using the visual-world eye-tracking paradigm, we investigated whether clear speech also aids speech segmentation, or the discovery of word boundaries, and examined the dynamic time course of its effect. Native American English speakers (N = 77) heard sentences in which the target word (e.g., ham) was temporarily ambiguous with a longer unintended competitor (e.g., hamster) across a word boundary (e.g., She saw the ham starting…) while viewing images depicting the target, competitor, and unrelated distractors. Clear and conversational sentences were presented in quiet or in speech-shaped noise at +3 dB signal-to-noise ratio. Analysis of eye fixations to the images over time revealed that compared with conversational speech, clear speech facilitated the disambiguation of the target from the competitor even before the disambiguation point was reached. The facilitation was found in both listening conditions but was relatively delayed in noise. These findings suggest that speaking clearly improves word segmentation and reduces lexical competition especially in optimal listening conditions. The speech segmentation facilitation may partly underlie the clear speech benefits observed for other signal-dependent and relatively signal-independent linguistic and cognitive processes.

Production and Perception of Single and Double Consonant Letters in English Words by Korean Learners of English

This study investigates how Korean students produce and perceive single and double consonant letters in English words. To this end, twenty-eight Korean learners of English participated in the production and perception tests of English consonants /p, b, s, d, k, g/ with single and double letters. The participants were first asked to produce English words with the target consonants spelled with a single or a double letter. Then, the same participants were asked to choose the same words they heard among the two productions of each native American English speaker’ production: the original production and artificially lengthened production of the target consonant sound. The percentages of the correct production and perception for the target consonant sounds with single consonant letters and double consonant letters were calculated to compare the accuracy of single and double letters. The study results demonstrate three factors influencing the production and perception of English single and double consonant letters. First, the Korean participants’ performance of the double letters was significantly worse than the performance of the single letters for both perception and production. This clearly shows that orthographic forms affect the learners’ production and perception of English words. Second, modality effect was attested such that the participants’ perception of the English single and double letters was significantly worse than the production of the same targets. Third, the participants showed worse performance for the voiceless targets than for the voiced targets both in perception and production, thus showing voicing effect. Further, the participants’ production of the voiceless targets was significantly worse than the production of the voiced targets. Finally, pedagogical suggestions were provided.

Effects of Final Stop Release and Vowel Insertion on Nasalization in English Speech by Korean EFL Speakers

This study aims to investigate how Korean nasalization processes influence English speech by Korean EFL (English as Foreign Language) speakers as L1 interference. Specifically, the study focuses on the effects of final stop release and vowel insertion on nasalization. 24 speakers participated in the experiment. Among them, four speakers were Native American English speakers and 20 were Korean EFL speakers. The Korean-speaking participants were divided into two groups of ten according to their English proficiency; a group with high-intermediate English proficiency and a group with low English proficiency. Through this study, the following points were noted. First, the realization of final stop release and vowel insertion influences the realization of nasalization processes in English speech by Korean EFL speakers. The higher the frequency of final stop release and vowel insertion, the lower the frequency of the realization of nasalization processes when analyzed by prosodic domains and voicing and place of the final stops. Second, it was found that the effects of final stop release and vowel insertion on nasalization processes are more noticeable in the group with lower English proficiency than the group with higher English proficiency. These findings suggest that Korean nasalization processes influence English speech by Korean EFL speakers as L1 interference and the realization of Korean nasalization is closely related to the realization of final stop release and vowel insertion.

Gender and speech fluency in Mandarin and English news interviews

Speech fluency affects the effectiveness of speech communications. Previous research has been mostly looking at the fluency performances in L2 and in atypical population. This paper investigates the fluency pattern in news anchor’s natural interview speech, which represents the upper limit of native language fluency, and examines the effect of gender on fluency. We collected a gender-balanced corpus of audio clips of publicly accessible news programs by six native Mandarin speaking news anchors and six native American English news anchors. The total length of interview used in the analysis was 20 min for each language. This study examined six temporal and non-temporal measurements of fluency: temporal measures included speech rate, mean length of run (MLR), mean length of utterance (MLU), and mean length of pauses (MLP); non-temporal disfluency measures included syllable count and disfluency rate. The results showed that male Mandarin speakers had significantly lower MLR, lower MLU, and higher disfluency rates than female Mandarin speakers; no significant gender difference was found in MLP. The English data did not show any gender difference in any measurement. The results indicated that female Mandarin speakers spoke more fluently than male Mandarin speakers, while male English speakers and female speakers were equally fluent.

Behavioral Pattern Analysis between Bilingual and Monolingual Listeners’ Natural Speech Perception on Foreign-Accented English Language Using Different Machine Learning Approaches

Speech perception in an adverse background/noisy environment is a complex and challenging human process, which is made even more complicated in foreign-accented language for bilingual and monolingual individuals. Listeners who have difficulties in hearing are affected most by such a situation. Despite considerable efforts, the increase in speech intelligibility in noise remains elusive. Considering this opportunity, this study investigates Bengali–English bilinguals and native American English monolinguals’ behavioral patterns on foreign-accented English language considering bubble noise, gaussian or white noise, and quiet sound level. Twelve regular hearing participants (Six Bengali–English bilinguals and Six Native American English monolinguals) joined in this study. Statistical computation shows that speech with different noise has a significant effect (p = 0.009) on listening for both bilingual and monolingual under different sound levels (e.g., 55 dB, 65 dB, and 75 dB). Here, six different machine learning approaches (Logistic Regression (LR), Linear Discriminant Analysis (LDA), K-nearest neighbors (KNN), Naïve Bayes (NB), Classification and regression trees (CART), and Support vector machine (SVM)) are tested and evaluated to differentiate between bilingual and monolingual individuals from their behavioral patterns in both noisy and quiet environments. Results show that most optimal performances were observed using LDA by successfully differentiating between bilingual and monolingual 60% of the time. A deep neural network-based model is proposed to improve this measure further and achieved an accuracy of nearly 100% in successfully differentiating between bilingual and monolingual individuals.

Second Language Experience Facilitates Sentence Recognition in Temporally-Modulated Noise for Non-native Listeners.

Non-native listeners deal with adverse listening conditions in their daily life much harder than native listeners. However, previous work in our laboratories found that native Chinese listeners with native English exposure may improve the use of temporal fluctuations of noise for English vowel identification. The purpose of this study was to investigate whether Chinese listeners can generalize the use of temporal cues for the English sentence recognition in noise. Institute of Electrical and Electronics Engineers (IEEE) sentence recognition in quiet condition, stationary noise, and temporally-modulated noise were measured for native American English listeners (EN), native Chinese listeners in the United States (CNU), and native Chinese listeners in China (CNC). Results showed that in general, EN listeners outperformed the two groups of CN listeners in quiet and noise, while CNU listeners had better scores of sentence recognition than CNC listeners. Moreover, the native English exposure helped CNU listeners use high-level linguistic cues more effectively and take more advantage of temporal fluctuations of noise to process English sentence in severely degraded listening conditions [i.e., the signal-to-noise ratio (SNR) of −12 dB] than CNC listeners. These results suggest a significant effect of language experience on the auditory processing of both speech and noise.

Ejective production mechanisms in English

Ejective realization of stops seems to be increasing in many varieties of English, which has triggered a new debate on the basic mechanism of ejective production. While traditionally the glottalic initiation mechanism of ejectives is thought to require a closed glottis and active larynx raising, this has been questioned for the emergent English ejectives, and a pulmonic airstream mechanism has been suggested. In order to shed light on the possible production mechanism of English ejectives, we present rtMRI data acquired at 50fps from a corpus of 27 native British English and 18 native American English speakers. Auditory analysis of 20 BE-speakers from the corpus confirms that 26% of all word-final stops in target words are realized as ejectives. Our results so far agree with previous observations about the conditioning factors favoring ejective production. Ejectives occur predominantly in stressed position as allophones of word-final velar, less frequently of labial and coronal stops. Surprisingly, also phonemically voiced stops may be realized as ejectives. Importantly, the rtMRI data will allow us to measure larynx height and to observe the extent of active larynx movement involved in the initiation process in English ejectives. [Work supported by ERC Horizon 2020 grant Interaccent to J. Harrington.]

Recognising foreign-accented speech of varying intelligibility and linguistic complexity: insights from older listeners with or without hearing loss

Objective The goal of this study was to assess recognition of foreign-accented speech of varying intelligibility and linguistic complexity in older adults. It is important to understand the factors that influence the recognition of this commonly encountered type of speech, in a population that remains understudied in this regard. Design A repeated measures design was used. Listeners repeated back linguistically simple and complex sentences heard in noise. The sentences were produced by three talkers of varying intelligibility: one native American English, one foreign-accented talker of high intelligibility and one foreign-accented talker of low intelligibility. Percentage word recognition in sentences was measured. Study sample Twenty-five older listeners with a range of hearing thresholds participated. Results We found a robust interaction between talker intelligibility and linguistic complexity. Recognition accuracy was higher for simple versus complex sentences, but only for the native and high intelligibility foreign-accented talkers. This pattern was present after effects of working memory capacity and hearing acuity were taken into consideration. Conclusion Older listeners exhibit qualitatively different speech processing strategies for low versus high intelligibility foreign-accented talkers. Differences in recognition accuracy for words presented in simple versus in complex sentence contexts only emerged for speech over a threshold of intelligibility.

Concessive Connectors though and however in Writing of Native and Non-Native Speakers of English

This paper focuses on connectors though and however in Serbian EFL writing. The logical relationship established by the two connectors is concessive, the concept of concessiveness ranging from the very transparent cases, referred to as the strong ‘contrary-to-expectations’ implicature, to less transparent ones, referred to as the weak ‘contrary-to-expectations’ implicature. Besides, the two lexemes, though and however, can be used in other functional roles in the contemporary language; while though is more frequently used as a conjunction than as a connector, however is more frequently used as a connector than as an adverb.The research followed Contrastive Interlanguage Analysis (Granger, 2015). The data includes the three corpora of argumentative essays: a non-native one, ICLE-SE, belonging to the International Corpus of Learner English (ICLE, Université catholique de Louvain, Belgium), and two native ones, British English and American English subsets of the Louvain Corpus of Native English Essays (LOCNESS-BE and LOCNESS-AE, respectively). The research is mainly qualitative.The results have shown that though is almost never used as a connector in the non-native corpus—only 1.7% of the total number of uses occupy this functional role. In the native corpora, conversely, every second or third use is as a connector. The case of however is different. Although it is almost exclusively used as a connector in all the three corpora, there are striking differences in its uses. The initial position is strongly favoured by non-native writers, unlike native writers, who use the medial and the final positions considerably more frequently. Apart from the striking differences, there is also a similarity in the three corpora: there are cases of however directly following the so-called ‘run-on’ comma, which is seen as non-grammatical in the referential descriptive grammars.Finally, we conclude that logical connectors though and however are challenging for both descriptive linguistics and applied domains. It is quite expected, then, that they are a very demanding part of the language learning process, as the research has shown. It is suggested that the research results should be complemented by the classical contrastive analysis, focusing on the two connectors and their equivalents in Serbian.

Analysis of vowel production in Mandarin/Hindi/American- accented English for accent recognition systems

With globalization and emerging voice-activated systems, accent recognition systems have gained more importance. Foreign-accented English shows different acoustical characteristics from native English pronunciation. It varies based on native language of speakers. This work investigated the similarities and differences between spectral and time-domain characteristics of vowel production for English /hvd/ words spoken by native Mandarin, Hindi, and American English speakers. Fundamental frequency, the first four formants, mel-cepstral coefficients, linear predictive coefficients, harmonicity, spectral centroid, spectral spread, tonality, spectral flatness, pitch range coefficients, and zero crossings rate were examined for male and female speakers of English. One-way ANOVA was performed to find the significant correlations. Lindblom’s perceptual distance of the corner vowels was calculated for further analysis. Our preliminary findings indicated that the vowel spaces of the male L2 speakers were smaller than the male L1 speakers’ vowel space. The F1-F2 space of the corner vowel /ɑ/ presented the most variance among L1 and L2 speakers. The vowel space of the female Hindi-accented English was found to be nearly triangular shaped. For the vowels /i/ and /ɪ/, Mandarin- and Hindi-accented English showed similar characteristics. Short-time energy had significant means between L1 and L2 speakers (p < 0.001) for the vowels /i/ as in ‘heed’ and /ɪ/ as in ‘hid’. Higher F1 frequencies were calculated for the vowels /ӕ/ as in ‘had’, /ε/ as in ‘head’ and /ʌ/ as in ‘hud’ spoken by Mandarin-accented speakers. Time-domain based features provided noteworthy differences between the female L1 and L2 speakers of English. The baseline classification system showed that spectral features had higher impacts on recognizing Mandarin- and Hindi-accented English.

Acoustic cues and linguistic experience as factors in regional dialect classification.

Listeners are able to classify talkers by regional dialect of their native language when provided with even short speech samples. However, the way in which American English listeners use segmental and prosodic information to make such decisions is largely unknown. This study used a free classification task to assess native American English listeners' ability to group together talkers from six major dialect regions of American English. Listeners residing in Ohio and Texas were provided with a sentence-long (experiment 1) or paragraph-long (experiment 2) speech sample produced by talkers from each of the six regions presented in one of three conditions: unmodified, monotonized (i.e., flattened F0), and low-pass filtered (i.e., spectral information above 400 Hz removed). In both experiments, listeners in the unmodified and monotonized conditions made more accurate groupings, reflecting their reliance on segmental properties for classifying regional variation. Accuracy was highest for Northern and Western talkers (experiment 1) and Mid-Atlantic talkers (experiment 2). Listeners with experience with multiple dialects as a result of geographic mobility did not show increased accuracy, suggesting a complex relationship between linguistic experience and the perception of available acoustic cues to socioindexical variation.

What Makes Spanish-Accented English Sound Spanish-Accented? Acoustic Measures and Listener Cues

This study aimed to understand which acoustic parameters of Spanish-accented English are correlated with listeners’ perception of Spanish-accentedness. Temporal differences were analyzed in multisyllabic target words spoken in sentences by 22 Spanish speakers of English and five native speakers of American English (AE). Recordings were presented to AE listeners who judged the degree of accentedness on a 9-point scale. Spearman rank order correlation showed that the listeners’ ratings of degree of accentedness in sentences correlated strongly (r= +0.82) with those in words. Listeners’ ratings of accentedness correlated in varying degrees with various temporal measures, namely Overall word durations (+0.04 to +0.56), Stressed/unstressed vowel duration ratios (–0.01 to +0.35), Voice Onset Time of stops (+0.26 to +0.36), and, closure duration (+0.29 to +0.59). Results suggest that Spanish-accented English is characterized by systematic temporal differences from native AE, and that these temporal differences contribute to the perception of accentedness. Implications of findings in improving theoretical understanding and applied practices are discussed.