Effects of Language History on Sentence Recognition in Noise or Two-Talker Speech: Monolingual, Early Bilingual, and Late Bilingual Speakers of English

The relationship between speech in noise perception and auditory working memory capacity in monolingual and bilingual adults

OBJECTIVE

Speech-in-noise perception is dependent on the interaction between sensory and cognitive processes. One factor that can relate to both processes is bilingualism. This study aimed to determine the correlation between auditory-working-memory and speech-in-noise in Persian monolinguals and Kurdish-Persian bilinguals.

DESIGN

Speech-in-noise tests (sentences-in-noise and syllables-in-noise) and auditory-working-memory tests (forward and backward digit span, and n-back) were performed.

STUDY SAMPLE

Participants were 48 Kurdish-Persian bilinguals with a mean age of 24 (±4) years and 48 Persian monolinguals with a mean age of 25 (±2) years with normal hearing.

RESULTS

Both language groups scored within normal limits in all memory and speech-in-noise tests. However, bilinguals performed significantly worse than monolinguals on all auditory-working-memory tests and the sentences-in-noise test. Monolinguals outperformed bilinguals in sentences-in-noise test (∼1.5 dB difference) and all auditory-working-memory tests (∼1 digit difference). The two groups did not significantly differ in syllables-in-noise test. Both groups had a significant correlation between working memory capacity and sentences-in-noise test. However, no significant correlation was found between syllables-in-noise and working memory capacity at any SNR.

CONCLUSIONS

Cognitive factors such as auditory working memory appear to correlate with speech-in-noise perception ability (at least at the sentence level) in monolingual and bilinguals young adults.

Exploring audiovisual speech perception in monolingual and bilingual children in Uzbekistan

This study aimed to investigate the development of audiovisual speech perception in monolingual Uzbek-speaking and bilingual Uzbek-Russian-speaking children, focusing on the impact of language experience on audiovisual speech perception and the role of visual phonetic (i.e., mouth movements corresponding to phonetic/lexical information) and temporal (i.e., timing of speech signals) cues. A total of 321 children aged 4 to 10 years in Tashkent, Uzbekistan, discriminated /ba/ and /da/ syllables across three conditions: auditory-only, audiovisual phonetic (i.e., sound accompanied by mouth movements), and audiovisual temporal (i.e., sound onset/offset accompanied by mouth opening/closing). Effects of modality (audiovisual phonetic, audiovisual temporal, or audio-only cues), age, group (monolingual or bilingual), and their interactions were tested using a Bayesian regression model. Overall, older participants performed better than younger participants. Participants performed better in the audiovisual phonetic modality compared with the auditory modality. However, no significant difference between monolingual and bilingual children was observed across all modalities. This finding stands in contrast to earlier studies. We attribute the contrasting findings of our study and the existing literature to the cross-linguistic similarity of the language pairs involved. When the languages spoken by bilinguals exhibit substantial linguistic similarity, there may be an increased necessity to disambiguate speech signals, leading to a greater reliance on audiovisual cues. The limited phonological similarity between Uzbek and Russian might have minimized bilinguals' need to rely on visual speech cues, contributing to the lack of group differences in our study.

The Involvement of Listening Effort in Explaining Bilingual Listening Under Adverse Listening Conditions

The current review examines listening effort to uncover how it is implicated in bilingual performance under adverse listening conditions. Various measures of listening effort, including physiological, behavioral, and subjective measures, have been employed to examine listening effort in bilingual children and adults. Adverse listening conditions, stemming from environmental factors, as well as factors related to the speaker or listener, have been examined. The existing literature, although relatively limited to date, points to increased listening effort among bilinguals in their nondominant second language (L2) compared to their dominant first language (L1) and relative to monolinguals. Interestingly, increased effort is often observed even when speech intelligibility remains unaffected. These findings emphasize the importance of considering listening effort alongside speech intelligibility. Building upon the insights gained from the current review, we propose that various factors may modulate the observed effects. These include the particular measure selected to examine listening effort, the characteristics of the adverse condition, as well as factors related to the particular linguistic background of the bilingual speaker. Critically, further research is needed to better understand the impact of these factors on listening effort. The review outlines avenues for future research that would promote a comprehensive understanding of listening effort in bilingual individuals.

Masked-Speech Recognition for Linguistically Diverse Populations: A Focused Review and Suggestions for the Future

PURPOSE

Twenty years ago, von Hapsburg and Peña (2002) wrote a tutorial that reviewed the literature on speech audiometry and bilingualism and outlined valuable recommendations to increase the rigor of the evidence base. This review article returns to that seminal tutorial to reflect on how that advice was applied over the last 20 years and to provide updated recommendations for future inquiry.

METHOD

We conducted a focused review of the literature on masked-speech recognition for bilingual children and adults. First, we evaluated how studies published since 2002 described bilingual participants. Second, we reviewed the literature on native language masked-speech recognition. Third, we discussed theoretically motivated experimental work. Fourth, we outlined how recent research in bilingual speech recognition can be used to improve clinical practice.

RESULTS

Research conducted since 2002 commonly describes bilingual samples in terms of their language status, competency, and history. Bilingualism was not consistently associated with poor masked-speech recognition. For example, bilinguals who were exposed to English prior to age 7 years and who were dominant in English performed comparably to monolinguals for masked-sentence recognition tasks. To the best of our knowledge, there are no data to document the masked-speech recognition ability of these bilinguals in their other language compared to a second monolingual group, which is an important next step. Nonetheless, individual factors that commonly vary within bilingual populations were associated with masked-speech recognition and included language dominance, competency, and age of acquisition. We identified methodological issues in sampling strategies that could, in part, be responsible for inconsistent findings between studies. For instance, disparities in socioeconomic status (SES) between recruited bilingual and monolingual groups could cause confounding bias within the research design.

CONCLUSIONS

Dimensions of the bilingual linguistic profile should be considered in clinical practice to inform counseling and (re)habilitation strategies since susceptibility to masking is elevated in at least one language for most bilinguals. Future research should continue to report language status, competency, and history but should also report language stability and demand for use data. In addition, potential confounds (e.g., SES, educational attainment) when making group comparisons between monolinguals and bilinguals must be considered.

Speaker-listener neural coupling reveals a right-lateralized mechanism for non-native speech-in-noise comprehension

While the increasingly globalized world has brought more and more demands for non-native language communication, the prevalence of background noise in everyday life poses a great challenge to non-native speech comprehension. The present study employed an interbrain approach based on functional near-infrared spectroscopy (fNIRS) to explore how people adapt to comprehend non-native speech information in noise. A group of Korean participants who acquired Chinese as their non-native language was invited to listen to Chinese narratives at 4 noise levels (no noise, 2 dB, -6 dB, and - 9 dB). These narratives were real-life stories spoken by native Chinese speakers. Processing of the non-native speech was associated with significant fNIRS-based listener-speaker neural couplings mainly over the right hemisphere at both the listener's and the speaker's sides. More importantly, the neural couplings from the listener's right superior temporal gyrus, the right middle temporal gyrus, as well as the right postcentral gyrus were found to be positively correlated with their individual comprehension performance at the strongest noise level (-9 dB). These results provide interbrain evidence in support of the right-lateralized mechanism for non-native speech processing and suggest that both an auditory-based and a sensorimotor-based mechanism contributed to the non-native speech-in-noise comprehension.

Online Simulation Education for Audiometry Training

PURPOSE

The purpose of this clinical focus article was to describe a new online simulation program for pure-tone audiometry.

METHOD

Fictional but realistic patient profiles and testing environments were created to teach students about hearing screening protocols and pure-tone audiology. The diversity of the demographics of the United States is represented throughout the program. The web app was created using HTML/JS/CSS with a Flask server backend and MySQL database.

RESULTS

The program allows students to learn the process of conducting a hearing screening and measuring audiometric thresholds using a web-based virtual clinical audiometer. The virtual audiometer includes standard audiometer features and allows for instruction based on standard guidelines. The diversity of the patients within the simulation program allows for discussions of diversity to be woven throughout the curriculum.

CONCLUSIONS

The new simulation program is designed for use as a clinical training tool enabling undergraduate and graduate students to actively participate in hearing screening testing and pure-tone audiometry using any web browser. The program is also designed with the intent to improve pedagogical outcomes at the undergraduate and graduate level for communication sciences and disorders education for pure-tone audiometry by providing instructors with content that focuses on the diversity that is represented in the demographics of the United States.

A Simplified Approach to Quantifying a Child's Bilingual Language Experience

Purpose Bilingual children's linguistic experience can vary markedly from child to child. For appropriate audiological assessment and intervention, audiologists need accurate and efficient ways to describe and understand a bilingual child's dynamic linguistic experience. This report documents an approach for quantitatively capturing a child's language exposure and usage in a time-efficient manner. Method A well-known pediatric bilingual language survey was administered to 83 parents of bilingual children, obtaining information about the child's exposure to (input) and usage of (output) Spanish and English for seventeen 1-hr intervals during a typical weekday and weekend day. Results A factor analysis indicated that capturing linguistic exposure and usage over three grouped-time intervals during a typical weekday and weekend day accounted for ≥ 74% of the total variance of the linguistic information captured with the full-length survey. Conclusions Although further confirmation is required, these results suggest that collecting language exposure and usage data from parents of bilingual children for three grouped-time intervals provides similar information as a comprehensive hour-by-hour approach. A time-efficient method of capturing the dynamic bilingual linguistic experience of a child would benefit pediatric audiologists and speech-language pathologists alike.

Masked English Speech Recognition Performance in Younger and Older Spanish-English Bilingual and English Monolingual Children

Purpose The purpose of this study was to compare masked English speech recognition thresholds between Spanish-English bilingual and English monolingual children and to evaluate effects of age, maternal education, and English receptive language abilities on individual differences in masked speech recognition. Method Forty-three Spanish-English bilingual children and 42 English monolingual children completed an English sentence recognition task in 2 masker conditions: (a) speech-shaped noise and (b) 2-talker English speech. Two age groups of children, younger (5-6 years) and older (9-10 years), were tested. The predictors of masked speech recognition performance were evaluated using 2 mixed-effects regression models. In the 1st model, fixed effects were age group (younger children vs. older children), language group (bilingual vs. monolingual), and masker type (speech-shaped noise vs. 2-talker speech). In the 2nd model, the fixed effects of receptive English vocabulary scores and maternal education level were also included. Results Younger children performed more poorly than older children, but no significant difference in masked speech recognition was observed between bilingual and monolingual children for either age group when English proficiency and maternal education were also included in the model. English language abilities fell within age-appropriate norms for both groups, but individual children with larger receptive vocabularies in English tended to show better recognition; this effect was stronger for younger children than for older children. Speech reception thresholds for all children were lower in the speech-shaped noise masker than in the 2-talker speech masker. Conclusions Regardless of age, similar masked speech recognition was observed for Spanish-English bilingual and English monolingual children tested in this study when receptive English language abilities were accounted for. Receptive English vocabulary scores were associated with better masked speech recognition performance for both bilinguals and monolinguals, with a stronger relationship observed for younger children than older children. Further investigation involving a Spanish-dominant bilingual sample is warranted given the high English language proficiency of children included in this study.