Non-native English Listeners Research Articles

Audiovisual perception of interrupted speech by nonnative listeners.

The purpose of the present study was to examine the influence of visual cues in audiovisual perception of interrupted speech by nonnative English listeners and to identify the role of working memory, long-term memory retrieval, and vocabulary knowledge in audiovisual perception by nonnative listeners. The participants included 31 Mandarin-speaking English learners between 19 and 41 years of age. The perceptual stimuli were noise-filled periodically interrupted AzBio and QuickSIN sentences with or without visual cues that showed a male speaker uttering the sentences. In addition to sentence recognition, the listeners completed a semantic fluency task, verbal (operation span) and visuospatial (symmetry span) working memory tasks, and two vocabulary knowledge tests (Vocabulary Level Test and Lexical Test for Advanced Learners of English). The results revealed significantly better speech recognition in the audio-visual condition than the audio-only condition, but the magnitude of visual benefit was substantially attenuated for sentences that had limited semantic context. The listeners' vocabulary size in English played a key role in the restoration of missing speech information and audiovisual integration in the perception of interrupted speech. Meanwhile, the listeners' verbal working memory capacity played an important role in audiovisual integration especially for the difficult stimuli with limited semantic context.

Effect of room acoustics on speech intelligibility under noise between native and non-native listeners

The current study investigates the effect of room acoustics on the perception of speech between native and non-native listeners of English. The study particularly focuses on how the benefit of spatial release from masking (SRM) is affected by room acoustics for the different listener groups. The result of subjective listening test shows that SRM is observed both from native and non-native listeners, however the drop in the speech intelligibility is more significant in the non-native listeners when the sound sources are located farther away from the listener.

Non-native listeners perceiving foreign accentedness of English speech: new evidence from Chinese and Spanish listeners

As an international language, English is an important tool for people of different native languages to communicate with each other. Many empirical studies, proving that foreign accents are prevalent in L2 learners’ oral English, involved native speakers as raters of foreign accents. This study compared the rating patterns of listeners from Chinese, Spanish and English language backgrounds with different English proficiencies for foreign accents in English speech and investigated the acoustical cues used by these listeners. Results showed that Chinese listeners, sharing language backgrounds with talkers, tended to be more tolerant for the Chinese accent in English speech. Spanish listeners had a stricter criterion for mild Chinese accents, proving that the influence of listeners’ L1 on their perception of foreign accents can be different for different degrees of accents. The effects of listeners’ L2 proficiency was found for Chinese listeners’ perception of accents and the number of acoustic predictors used by non-native English listeners. The study provides more evidence about the mechanism of native and non-native listeners’ perception of foreign accent and offers implications for the recruitment of raters for the assessment of oral English.

Intelligibility of Noise-Adapted and Clear Speech in Energetic and Informational Maskers for Native and Nonnative Listeners.

This study explored clear speech (CS) and noise-adapted speech (NAS) intelligibility benefits for native and nonnative English listeners. It also examined how the two speaking style adaptations interact with maskers that vary from purely energetic to largely informational at different signal-to-noise ratios (SNRs). Materials consisted of 40 sentences produced by 10 young adult talkers in a conversational and a clear speaking style under two conditions: (a) in quiet and (b) in response to speech-shaped noise (SSN) played over headphones (NAS). Young adult native (Experiment 1) and nonnative (Experiment 2) English listeners heard target sentences presented in two-talker (2T) babble, six-talker (6T) babble, or SSN and at an "easier" and a "harder" SNR. When talkers produced CS and NAS, word recognition accuracy was significantly improved for both listener groups. The largest intelligibility benefit was obtained for the CS produced in response to noise (CS+NAS). Overall accuracy was highest in 2T babble. Accuracy was higher in SSN than in 6T babble for nonnative listeners at both levels of listening difficulty but only at a more difficult SNR for native listeners. Listeners benefited from CS and NAS most in the presence of SSN and least in 2T babble. When SNRs were the same for the two listener groups, native listeners outperformed nonnative listeners in almost all listening conditions, but nonnative listeners benefited more from CS and NAS in 6T babble than native listeners did. Combined speaking style enhancements, CS+NAS, provided the largest intelligibility increases for native and nonnative listeners in all listening conditions. The results add to the body of evidence supporting speech-oriented, behavioral therapy techniques for maximizing speech intelligibility in everyday listening situations.

Non-native English listeners' adaptation to native English speakers.

Listeners often have difficulty understanding unfamiliar speech (e.g., non-native speech), but they are able to adapt to or improve their ability to understand unfamiliar speech. However, it is unclear whether non-native listeners demonstrate adaptation to novel native English speech broadly with relatively limited exposure. Thus, this study examines non-native English listeners' adaptation to native English speakers and whether talker variability affects adaptation. Results suggest that while greater variability initially disrupts non-native English listeners' perception of native English speakers, listeners are able to rapidly adapt to novel speakers and exposure to greater variability could result in cross-talker generalization.

Perceptual restoration of locally time-reversed speech: Non-native listeners\u2019 performance in their L2 vs. L1

Nonnative listeners are generally not as good as native listeners in perceptually restoring degraded speech and understand what was being said. The current study investigates how nonnative listeners of English (namely, native Japanese speakers who learned English as a second language) perceptually restore temporally distorted speech in their L2 English as compared with native English listeners (L1 English) reported in Ishida et al. (Cognition, 151, 68–75, 2016), and as compared with the listeners’ native tongue (L1 Japanese). In the experiment, listeners listened to locally time-reversed words and pseudowords in their L2 English and L1 Japanese where every 10, 30, 50, 70, 90, or 110 ms of speech signal was flipped in time—these stimuli contained either many fricatives or stops. The results suggested that the intelligibility of locally time-reversed words and pseudowords deteriorated as the length of reversed segments increased in both listeners’ L2 English and L1 Japanese, while listeners understood locally time-reversed speech more in their L1 Japanese. In addition, lexical context supported perceptual restoration in both listeners’ L1 Japanese and L2 English, while phonemic constituents affected perceptual restoration significantly only in listeners’ L1. On the other hand, locally time-reversed words and pseudowords in L1 Japanese were much more intelligible than those in L1 English reported in Ishida et al. It is possible that the intelligibility of temporally distorted lexical items depends on the structure of basic linguistic units in each language, and the Japanese language might have a unique characteristic because of its CV and V structure.

Neural tracking of the speech envelope is differentially modulated by attention and language experience

The ability to selectively attend to a speech signal amid competing sounds is a significant challenge, especially for listeners trying to comprehend non-native speech. Attention is critical to direct neural processing resources to the most essential information. Here, neural tracking of the speech envelope of an English story narrative and cortical auditory evoked potentials (CAEPs) to non-speech stimuli were simultaneously assayed in native and non-native listeners of English. Although native listeners exhibited higher narrative comprehension accuracy, non-native listeners exhibited enhanced neural tracking of the speech envelope and heightened CAEP magnitudes. These results support an emerging view that although attention to a target speech signal enhances neural tracking of the speech envelope, this mechanism itself may not confer speech comprehension advantages. Our findings suggest that non-native listeners may engage neural attentional processes that enhance low-level acoustic features, regardless if the target signal contains speech or non-speech information.

An Automated Speech-in-Noise Test for Remote Testing: Development and Preliminary Evaluation.

Purpose The aim of this study was to develop and evaluate a novel, automated speech-in-noise test viable for widespread in situ and remote screening. Method Vowel-consonant-vowel sounds in a multiple-choice consonant discrimination task were used. Recordings from a professional male native English speaker were used. A novel adaptive staircase procedure was developed, based on the estimated intelligibility of stimuli rather than on theoretical binomial models. Test performance was assessed in a population of 26 young adults (YAs) with normal hearing and in 72 unscreened adults (UAs), including native and nonnative English listeners. Results The proposed test provided accurate estimates of the speech recognition threshold (SRT) compared to a conventional adaptive procedure. Consistent outcomes were observed in YAs in test/retest and in controlled/uncontrolled conditions and in UAs in native and nonnative listeners. The SRT increased with increasing age, hearing loss, and self-reported hearing handicap in UAs. Test duration was similar in YAs and UAs irrespective of age and hearing loss. The test-retest repeatability of SRTs was high (Pearson correlation coefficient = .84), and the pass/fail outcomes of the test were reliable in repeated measures (Cohen's κ = .8). The test was accurate in identifying ears with pure-tone thresholds > 25 dB HL (accuracy = 0.82). Conclusion This study demonstrated the viability of the proposed test in subjects of varying language in terms of accuracy, reliability, and short test time. Further research is needed to validate the test in a larger population across a wider range of languages and hearing loss and to identify optimal classification criteria for screening purposes.

The effect of clear speech and masking noise on listening effort in native and non-native listeners

Listening effort increases when perceiving speech masked by noise and when listeners are non-native speakers of the target language (Zekveld and Kramer, 2014; Borghini and Hazan, 2018). Listener-oriented clear speech (CS) improves word recognition in noise and recognition memory (Keerstock and Smiljanic, 2018). It is unclear, however, whether the CS benefit can be explained by reduced listening effort during processing of easier-to-understand speech. The goal of this study was to examine the effect of CS on listening effort associated with degraded listening conditions differing in the source of difficulty and underlying cognitive mechanism: energetic masking, informational masking, and non-native listening. Native and non-native English listeners performed a word recognition in noise task and a visual response task, i.e., pressing keys to indicate the orientation of an arrow on the screen, first separately and then simultaneously. In the word recognition task, listeners repeated back sentences produced in CS and conversational speech and mixed with speech-shaped noise and 2-talker babble. The presentation will discuss analyses aimed at uncovering how hyper-articulated CS and masker type influence listening effort for native and non-native listeners as measured by objective and subjective dual-task cost.

The effects of Hong Kong L2 English speakers’ phonological features on listeners’ cognitive and affective perceptions

AbstractThis study explores the most perceivable phonological features of Hong Kong (HK) L2 English speakers and how they affect the perception of HK L2 English speech from the perspective of both native and non-native English listeners. Conversational interviews were conducted to collect speech data from 20 HK speakers of English and 10 native speakers of English in the United Kingdom. Phonological features of 20 HK speakers of English were analyzed at both segmental and suprasegmental levels. Forty listeners with different language backgrounds were recruited to listen and rate the speech samples of the 20 HK speakers of English in terms of the cognitive perception of foreign accentedness and comprehensibility and affective perception of likability and acceptability. This study identifies the phonological variables that contribute significantly to listeners’ perception of accentedness, comprehensibility, likability, acceptability, and overall impression of HK speakers’ English speech.

Sentence recognition for native and non-native English listeners in quiet and babble: Effects of contextual cues.

The purpose of this study was to investigate the difference between English-native (EN) listeners and Chinese-native (CN) listeners using contextual cues to perceive speech in quiet and four-talker babble in English. Three types of sentences served as speech stimuli: high (semantic and syntactic cues), low (syntactic cues), and zero predictability. Results showed that CN listeners primarily relied on semantic information when perceiving speech, whereas EN listeners used both semantic and syntactic cues more equally. Moreover, the four-talker babble enlarged the group difference similarly across the three types of sentences, indicating that non-native listeners' greater-than-native difficulty in noise depended on speech materials.

Talker-familiarity benefit in non-native recognition memory and word identification: The role of listening conditions and proficiency.

Native listeners benefit from talker familiarity in recognition memory and word identification, especially in adverse listening conditions. The present study addresses the talker familiarity benefit in non-native listening, and the role of listening conditions and listeners' lexical proficiency in the emergence of this benefit. Dutch non-native listeners of English were trained to identify four English talkers over 4 days. Talker familiarity benefit in recognition memory was investigated using a recognition memory task with "old" and "new" words produced by familiar and unfamiliar talkers presented either in the clear or in noise. Talker familiarity benefit in word identification was investigated by comparing non-native listeners' performances on the first and the last day in identifying words in different noise levels, produced by either a trained (included in the voice recognition training) or by an untrained talker (not included in the voice recognition training). Non-native listeners demonstrated a talker familiarity benefit in recognition memory, which was modulated by listening conditions and proficiency in the non-native language. No talker familiarity benefit was found in word identification. These results suggest that, similar to native listening, both linguistic and indexical (talker-specific) information influence non-native speech perception. However, this is dependent on the task and type of speech recognition process involved.

Cross-linguistic Influences on Sentence Accent Detection in Background Noise.

This paper investigates whether sentence accent detection in a non-native language is dependent on (relative) similarity between prosodic cues to accent between the non-native and the native language, and whether cross-linguistic differences in the use of local and more widely distributed (i.e., non-local) cues to sentence accent detection lead to differential effects of the presence of background noise on sentence accent detection in a non-native language. We compared Dutch, Finnish, and French non-native listeners of English, whose cueing and use of prosodic prominence is gradually further removed from English, and compared their results on a phoneme monitoring task in different levels of noise and a quiet condition to those of native listeners. Overall phoneme detection performance was high for the native and the non-native listeners, but deteriorated to the same extent in the presence of background noise. Crucially, relative similarity between the prosodic cues to sentence accent of one’s native language compared to that of a non-native language does not determine the ability to perceive and use sentence accent for speech perception in that non-native language. Moreover, proficiency in the non-native language is not a straightforward predictor of sentence accent perception performance, although high proficiency in a non-native language can seemingly overcome certain differences at the prosodic level between the native and non-native language. Instead, performance is determined by the extent to which listeners rely on local cues (English and Dutch) versus cues that are more distributed (Finnish and French), as more distributed cues survive the presence of background noise better.

Recall of clearly spoken sentences

Recognition memory (i.e., identifying items as old or new) is higher for sentences spoken clearly than for sentences spoken casually. The clear speech benefit on recognition memory was observed for both native and non-native English listeners. The current study investigated the effect of clear speech on sentence recall, a more complex and effortful type of declarative memory that requires processing at phonological, lexical-semantic, morphosyntactic, and syntactic levels. Thirty native and 30 non-native English listeners heard 72 meaningful sentences (e.g., “The grandfather drank the dark coffee”) produced in conversational and clear speaking styles by a female native English speaker. Participants were presented with 12 sentences blocked by speaking style, and instructed to memorize them. After each block of 12 sentences, participants wrote down what they remembered. Blocks were counterbalanced for speaking style. Responses were scored by number of keywords correctly recalled (verbatim memory) and sentence-level comprehension (gist memory). Preliminary results show enhanced verbatim memory for clear speech (i.e., higher rate of key words correctly recalled for sentences produced in clear speech) for both listener groups suggesting that hyper-articulated clear speech provides cognitive release and aids retention of surface form.

The direct and indirect effects of the phonotactic constraints in the listener’s native language on the comprehension of reduced and unreduced word pronunciation variants in a foreign language

This study investigates how the comprehension of casual speech in foreign languages is affected by the phonotactic constraints in the listener’s native language. Non-native listeners of English with different native languages heard short English phrases produced by native speakers of English or Spanish and they indicated whether these phrases included can or can’t. Native Mandarin listeners especially tended to interpret can’t as can. We interpret this result as a direct effect of the ban on word-final /nt/ in Mandarin. Both the native Mandarin and the native Spanish listeners did not take full advantage of the subsegmental information in the speech signal cueing reduced can’t. This finding is probably an indirect effect of the phonotactic constraints in their native languages: these listeners have difficulties interpreting the subsegmental cues because these cues do not occur or have different functions in their native languages. Dutch resembles English in the phonotactic constraints relevant to the comprehension of can’t, and native Dutch listeners showed similar patterns in their comprehension of native and non-native English to native English listeners. This result supports our conclusion that the major patterns in the comprehension results are driven by the phonotactic constraints in the listeners’ native languages.

Linguistic dimensions of second language accent and comprehensibility

The current study investigated the effect of listener status (native, nonnative) and language background (French, Mandarin) on global ratings of second language speech. Twenty-six nonnative English listeners representing the two language backgrounds (n = 13 each) rated the comprehensibility and accentedness of 40 French speakers of English. These same speakers were previously rated by native listeners and coded for 19 linguistic measures of speech (e.g., segmental errors, word stress errors, grammar accuracy) in Trofimovich and Isaacs (2012). Analyses indicated no difference in global ratings between nonnative and native listeners, or between the two nonnative listener groups. Similarly, no major differences in the linguistic dimensions associated with each group’s ratings existed. However, analyses of verbal reports for a subset of nonnative listeners (n = 5 per group) demonstrated that each group attributed their ratings to somewhat different linguistic cues.

English

Prosody has been emphasised in second language (L2) pedagogy as a strong contribution to successful intercultural communication. As English and Chinese are typologically different languages (Chinese is a syllable-timed language while English a stress-timed language), many differences in stress and rhythmic patterns trouble Chinese learners of English. This study analy s es acoustic speech samples for 13 prosodic features collected from 16 Chinese L2 learners and examines the relative importance of various prosody features on language attitudes that native and non-native English listeners hold towards Chinese-accented speech . The results revealed that Chinese speakers have a relatively slow speech rate and produce more stressed words in their English speech compared with native English speakers. W hen listeners heard long and inappropriate silent pauses in the speech, the integrity rating of the speakers decreased. The speech rate contributed significantly to both attractiveness rating and competence rating. That is , listeners evaluated speakers as more competent and attractive if the latter spoke faster. Keywords : L2 fluency; rhythmic patterns; foreign accent; pronunciation learning; language attitudes DOI: http://doi.org/10.17576/3L-2016-2202-07

Honking is just noise (or just about): The effect of energetic masking on recognition memory for spoken words

Previous research indicates that listeners encode both linguistic and indexical specifications of the speech signal in memory. Recent evidence suggests that non-linguistic sounds co-occurring with spoken words are also incorporated in our lexical memory. We argue that this “sound-specificity effect” might not be due so much to a word-sound association as to the different acoustic glimpses of the words that the associated sounds create. In several recognition-memory experiments, we paired spoken words with one of two car honk sounds and varied the level of energetic masking from exposure to test. We did not observe a drop in recognition accuracy for previously heard words when the paired sound changed as long as energetic masking was controlled. However, when we manipulated the temporal overlap between words and honking to create an energetic masking contrast, accuracy dropped. The finding suggests that listeners encode irrelevant non-speech information in memory, but only in certain contexts. Calling for an expansion of the mental lexicon to include non-speech auditory information might be premature. Current work is investigating the effect in non-native listeners of English, and whether maskers that are more integral to the words and hence more difficult to segregate lead to a more robust effect.

“Listen and Understand What I Am Saying”: Church-Listening As a Challenge for Non-Native Listeners of English in the United Kingdom

This article uses computer-assisted analysis to study the listening environment provided by Bible readings and preaching during church services. It focuses on the vocabulary size needed to comprehend 95% and 98% of the running words of the input (lexical coverage levels indicating comprehension in connection with listening) and on the place of infrequent vocabulary in liturgical discourse. The finding that 4,000 words and 7,000 words, respectively, are needed to reach the target levels for lexical coverage suggests that non-native listeners with vocabularies of just a few thousand words may be seriously challenged by church listening.

Effects of room acoustics on subjective workload assessment while performing dual tasks

This investigation examines the subjective workload assessments of individuals using the NASA Task Load Index (TLX), as they performed speech comprehension tests under assorted room acoustic conditions. This study was motivated due to the increasing diversity in US classrooms. Both native and non-native English listeners participated, using speech comprehension test materials produced by native English speakers in the first phase and by native Mandarin Chinese speakers in the second phase. The speech materials were disseminated in an immersive listening environment to each listener under 15 acoustic conditions, from combinations of background noise level (three levels from RC-30, 40, and 50) and reverberation time (five levels from 0.4 to 1.2 seconds). During each condition, participants completed assorted speech comprehension tasks while also tracing a moving dot for an adaptive rotor pursuit task. At the end of each acoustic condition, listeners were asked to assess the perceived workload by completing the six-item NASA TLX survey, e.g., mental demand, perceived performance, effort, and frustration. Results indicate that (1) listeners’ workload assessments degraded as the acoustic conditions became more adverse, and (2) the decrement in subjective assessment was greater for non-native listeners.