Speech Production Accuracy and Variability in Monolingual and Bilingual Children With Cochlear Implants: A Comparison to Their Peers With Normal Hearing

The Effects of Home Language Use on Spanish Speech Measures in Bilingual Children With Hearing Loss Who Use Cochlear Implants and Their Peers With Normal Hearing

PURPOSE

The purpose of this study was to investigate how the amount of home language use between the primary caregiver and bilingual Spanish- and English-speaking children with hearing loss who use cochlear implants (CIs) versus their bilingual age-matched peers with normal hearing (NH) can impact speech outcomes in the home language.

METHOD

Thirty-four bilingual Spanish- and English-speaking children (17 CI users and 17 with NH) between the ages of 5;3 and 7;9 (years;months) participated in this study. Independent variables were the amount of home language use with the primary caregiver and hearing status, and dependent variables were vowels and consonants correctly produced and occurrence of selected phonological processes. The amount of home language use was ascertained from surveys, and the dependent measures were based on a single-word picture elicitation task.

RESULTS

Bilingual children with CIs who are exposed to Spanish for more than 80% of the time via their primary caregiver performed better on Spanish segmental accuracy measures than those who are exposed to Spanish from only 20% to 50% of the time, specifically on vowels (partial η2 = .31) and consonants (partial η2 = .025). Children with NH outperformed children with CIs on all accuracy measures in Spanish.

CONCLUSIONS

Preliminary results suggest the importance of language exposure through interactions with the primary caregiver for speech development in bilingual children. Future studies should investigate strategies to facilitate home language development in bilingual children with CIs, enabling them to reach their full potential.

Speech production skills of bilingual children using cochlear implants

Evidence is lacking on the impact of bilingualism on the speech skills of children with cochlear implants (CIs). This study described the speech production of children with CIs acquiring French and one or more additional spoken languages. Four groups of children aged 4-11 were included: bilinguals (n = 15) and monolinguals (n = 14) with CIs and bilinguals (n = 14) and monolinguals (n = 20) with typical hearing. Data were collected about the percentage of consonant correct (PCC) and vowel correct (PVC) produced in French and intelligibility in all languages they spoke. Bilingual and monolingual children with CIs had comparable speech accuracy in French, but the pattern differed, impacting PCC for bilinguals and PVC for monolinguals. Most children with CIs had accurate and intelligible speech in French, but few bilingual children with CIs were highly intelligible in their home language. Therefore, bilingualism did not impede the speech production outcomes of bilingual children with CIs in the language of the wider community.

Factors affecting consonant production accuracy in children with cochlear implants: Expressive vocabulary and maternal education

BACKGROUND

Despite the ability of cochlear implants (CIs) to provide children with access to speech, there is considerable variability in spoken language outcomes. Research aimed at identifying factors influencing speech production accuracy is needed.

AIMS

To characterize the consonant production accuracy of children with cochlear implants (CWCI) and an age-matched group of children with typical hearing (CWTH) and to explore several factors that potentially affect the ability of both groups to accurately produce consonants.

METHODS & PROCEDURES

We administered the Bankson-Bernthal Test of Phonology (BBTOP) to a group of 25 CWCI (mean age = 4;9, SD = 1;6, range = 3;2-8;5) implanted prior to 30 months of age with a mean duration of implant usage of 3;6 and an age-matched group of 25 CWTH (mean age = 5;0, SD = 1;6, range = 3;1-8;6). The recorded results were transcribed, and the accuracy of the target consonants was determined. Expressive vocabulary size estimates were obtained from a language sample using the number of different words (NDW). A parent questionnaire provided information about maternal education, duration of CIs experience and other demographic characteristics of each child.

OUTCOMES & RESULTS

The CWCI group demonstrated some similarities to, and some differences from, their hearing peers. The CWCI demonstrated poorer consonant production accuracy overall and in various phonetic categories and word positions. However, both groups produced initial consonants more accurately than final consonants. Whilst CWCI had poorer production accuracy than CWTH for all phonetic categories (stops, nasals, fricatives, affricates, liquids and glides and consonant clusters), both groups exhibited similar error patterns across categories. For CWCI, the factors most related to consonant production accuracy when considered individually were expressive vocabulary size, followed by duration of CI experience, chronological age, maternal education and gender. The combination of maternal education and vocabulary size resulted in the best model of consonant production accuracy for this group. For the CWTH, chronological age followed by vocabulary size were most related to consonant production accuracy. No combination of factors yielded an improved model for the CWTH.

CONCLUSIONS & IMPLICATIONS

Whilst group differences in production accuracy between the CWCI and CWTH were found, the pattern of errors was similar for the two groups of children, suggesting that the children are at earlier stages of overall consonant production development. Although duration of CI experience was a significant covariate in a single-variable model of consonant production accuracy for CWCI, the best multivariate model of consonant production accuracy for these children was based on the combination of expressive vocabulary size and maternal education.

WHAT THIS PAPER ADDS

What is already known on the subject Research has shown that a range of factors is associated with consonant production accuracy by CWCIs, including factors such as the age at implant, duration of implant use, gender, other language skills and maternal education. Despite numerous studies that have examined speech sound production in these children, most have explored a limited number of factors that might explain the variability in scores obtained. Research that examines the potential role of a range of child-related and environmental factors in the same children is needed to determine the predictive role of these factors in speech production outcomes. What this paper adds to the existing knowledge Whilst the consonant production accuracy was lower for the CWCIs than for their typically hearing peers, there were some similarities suggesting that these children are experiencing similar, but delayed, acquisition of consonant production skills to that of their hearing peers. Whilst several factors are predictive of consonant production accuracy in children with implants, vocabulary diversity and maternal education, an indirect measure of socio-economic status, were the best combined predictors of consonant production accuracy. What are the potential or actual clinical implications of this work? Understanding the factors that shape individual differences in CWCI speech production is important for effective clinical decision-making and intervention planning. The present findings point to two potentially important factors related to speech sound production beyond the duration of robust hearing in CWCI, namely, a lexical diversity and maternal education. This suggests that intervention is likely most efficient that addresses both vocabulary development and speech sound development together. The current findings further suggest the importance of parental involvement and commitment to spoken language development and the importance of receiving early and consistent intervention aimed both at skill development and parental efficacy.

Measuring speech intelligibility with deaf and hard-of-hearing children: A systematic review

There is great variability in the ways in which the speech intelligibility of d/Deaf and hard-of-hearing (DHH) children who use spoken language as part, or all, of their communication system is measured. This systematic review examined the measures and methods that have been used when examining the speech intelligibility of children who are DHH and the characteristics of these measures and methods. A systematic database search was conducted of CENTRAL; CINAHL; Cochrane; ERIC; Joanna Briggs; Linguistics, Language and Behavior Abstracts; Medline; Scopus; and Web of Science databases, as well as supplemental searches. A total of 204 included studies reported the use of many different measures/methods which measured segmental aspects of speech, with the most common being Allen et al.'s (2001, The reliability of a rating scale for measuring speech intelligibility following pediatric cochlear implantation. Otology and Neurotology, 22(5), 631-633. https://doi.org/10.1097/00129492-200109000-00012) Speech Intelligibility Rating scale. Many studies included insufficient details to determine the measure that was used. Future research should utilize methods/measures with known psychometric validity, provide clear descriptions of the methods/measures used, and consider using more than one measure to account for limitations inherent in different methods of measuring the speech intelligibility of children who are DHH, and consider and discuss the rationale for the measure/method chosen.

Phonemic and pitch variability in bilingual preschoolers: A comparison of Jamaican Creole and English

PURPOSE

The purpose of this study was to investigate the cross-linguistic influences of Jamaican Creole (JC) and English on phonemic and vocal development in bilingual JC-English-speaking preschoolers.

METHOD

Sixteen typically developing children (12 females, M = 4 years; 4 months) completed the Diagnostic Evaluation of Articulation in Phonology Word Inconsistency Assessment subtest in JC and in English. Acoustic measures of voice onset time (VOT), VOT variability (VOT SD), mean fundamental frequency (fo), and fo variability (fo SD) were extracted from each target word. Prevoicing was noted. Mixed models and regression models were analysed to understand the patterns of acoustic measures in each language, and the relationship between phonemic and vocal variability, respectively.

RESULT

Analyses showed a significant effect of language on fo SD, wherein SD was greater in English than JC. JC spoken (percentage) was a significant positive predictor of VOT SD for voiced (short lag) productions. There was no relationship between phonemic and vocal variability measures.

CONCLUSION

Greater fo SD in English may be due to linguistic fo differences and speaking environment. Variability for voiced VOT is likely due to the continued maturation of vocal and articulatory control when children are developing adult-like productions, though longitudinal studies are needed.

Learning a Sign Language Does Not Hinder Acquisition of a Spoken Language

PURPOSE

The purpose of this study is to determine whether and how learning American Sign Language (ASL) is associated with spoken English skills in a sample of ASL-English bilingual deaf and hard of hearing (DHH) children.

METHOD

This cross-sectional study of vocabulary size included 56 DHH children between 8 and 60 months of age who were learning both ASL and spoken English and had hearing parents. English and ASL vocabulary were independently assessed via parent report checklists.

RESULTS

ASL vocabulary size positively correlated with spoken English vocabulary size. Spoken English vocabulary sizes in the ASL-English bilingual DHH children in the present sample were comparable to those in previous reports of monolingual DHH children who were learning only English. ASL-English bilingual DHH children had total vocabularies (combining ASL and English) that were equivalent to same-age hearing monolingual children. Children with large ASL vocabularies were more likely to have spoken English vocabularies in the average range based on norms for hearing monolingual children.

CONCLUSIONS

Contrary to predictions often cited in the literature, acquisition of sign language does not harm spoken vocabulary acquisition. This retrospective, correlational study cannot determine whether there is a causal relationship between sign language and spoken language vocabulary acquisition, but if a causal relationship exists, the evidence here suggests that the effect would be positive. Bilingual DHH children have age-expected vocabularies when considering the entirety of their language skills. We found no evidence to support recommendations that families with DHH children avoid learning sign language. Rather, our findings show that children with early ASL exposure can develop age-appropriate vocabulary skills in both ASL and spoken English.

Speech Error Variability and Phonological Awareness in Preschoolers

PURPOSE

The purpose of this article was to investigate the relationship between speech error variability and phonological awareness.

METHOD

This article begins with a narrative review of the theoretical interpretation of speech error variability. The post hoc exploratory analysis of the relationship between speech error variability and phonological awareness included 40 children: 20 with typical speech and language and 20 with speech sound disorder and typical language. Groups were matched on gender, age, maternal education, receptive and expressive vocabulary, nonverbal intelligence, and expressive morphosyntax. Multiple regression was used to identify the best fit model for the relationship between vocabulary, speech errors, and phonological awareness.

RESULTS

Segmental variability was associated with poor phonological awareness in preschool-aged children.

CONCLUSION

Children with high levels of segmental variability have poor phonological awareness, likely due to unstable phonological representations.

Intraword Variability in Children With Auditory Brainstem Implants: A Longitudinal Comparison With Children With Cochlear Implants

PURPOSE

Intraword variability designates the phenomenon that a particular target word is produced variably by a child at one point in the child's development. In this study, the amount of intraword variability is studied longitudinally in children with auditory brainstem implants (ABIs). Auditory brainstem implantation is a relative recent technique in pediatric hearing restoration. Therefore, little is known about the phonological development of these children's speech.

METHOD

The intraword variability is investigated in three children with ABI, in comparison to children with cochlear implants, matched on lexical development. Intraword variability is measured using relative entropy in order to take into account the frequency distribution in children's productions.

RESULT

Results showed considerable variation between the three children with ABI. Still, all children had higher levels of intraword variability in their spontaneous speech productions as compared to children with cochlear implants.

CONCLUSION

It seems that children with ABI are lagging behind their phonological development in reference to children with cochlear implants.

Home language maintenance in bilingual children with normal hearing and with hearing loss who use cochlear implants

We investigated home language (Spanish) maintenance in Spanish- and English-speaking bilingual children with normal hearing (NH) and their peers with hearing loss (HL) who used cochlear implants (CIs) at two time points about 7 months apart. Twenty-two bilingual children (11 with NH and 11 with CIs) between the ages of 4;6 and 7;11 participated in the study, who were matched as closely as possible on chronological age, time elapsed between the first and the second sample, gender, and age of exposure to their languages across groups. We compared group performance on the Preschool Language Scales - 5^th edition (PLS-5) and the Word Intelligibility Picture Identification at each time point as well as home language maintenance calculated based on item responses on the PLS-5. Our results indicated differences on all measures at both time points between the performance of children with NH and their peers with HL who used CIs in that the former group outperformed the latter. We also found that bilingual children with NH maintained their home language at a higher level than their peers with HL who used CIs. Further, the data also showed that despite the group differences, both groups displayed maintenance of their home language and that individual variability was more prevalent in the CI group. We conclude that home language maintenance is not only possible, but it should be encouraged for both bilingual children with NH and their peers with HL who used CIs.

Speech production in Mandarin-speaking children with cochlear implants: a systematic review

OBJECTIVE

This study aimed to systematically review and critically appraise the literature describing the phonetic characteristics and accuracy of the consonants, vowels and tones produced by Mandarin-speaking children with cochlear implants (CIs).

DESIGN

The protocol in this review was designed in conformity with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. EBSCOhost, PubMed, Scopus, PsycINFO, ProQuest Central databases were searched for relevant articles which met the inclusion criteria.

STUDY SAMPLE

A total of 18 journal papers were included in this review.

RESULTS

The results revealed that Mandarin-speaking children with CIs perform consistently more poorly in their production of consonants, in particular on fricatives, have a smaller and less well-defined vowel space, and exhibit greater difficulties in tone realisation, notably T2 and T3, when compared to their normal-hearing (NH) peers. The results from acoustic and accuracy analyses are negatively correlated with CI implantation age, but largely positively correlated with hearing age.

CONCLUSIONS

Findings of this review highlight the factors that influence consonant, vowel and tone production in Mandarin-speaking children with CIs, thereby providing critical information for clinicians and researchers working with this population.

Intraword Variability in French-Speaking Monolingual and Bilingual Children

Purpose This study examines intraword variability in 40 typically developing French-speaking monolingual and bilingual children, aged 2;6-4;8 (years;months). Specifically, it measures rate of intraword variability and investigates which factors best account for it. They include child-specific ones such as age, expressive vocabulary, gender, bilingual status, and speech sound production ability, and word-specific factors, such as phonological complexity (including number of syllables), phonological neighborhood density (PND), and word frequency. Method A variability test was developed, consisting of 25 words, which differed in terms of phonological complexity, PND, and word frequency. Children produced three exemplars of each word during a single session, and productions of words were coded as variable or not variable. In addition, children were administered an expressive vocabulary test and two tests tapping speech motor ability (oral motor assessment and diadochokinetic test). Speech sound ability was also assessed by measuring percent consonants correct on all words produced by the children during the session. Data were entered into a binomial logistic regression. Results Average intraword variability was 29% across all children. Several factors were found to predict intraword variability including age, gender, bilingual status, speech sound production ability, phonological complexity, and PND. Conclusions Intraword variability was found to be lower in French than what has been reported in English, consistent with phonological differences between French and English. Our findings support those of other investigators in indicating that the factors influencing intraword variability are multiple and reflect sources at various levels in the speech processing system.

Delayed Speech Perception and Production after Cochlear Implantation in Bilingual Children from Non-Native Families

The aim of the study was to evaluate the outcomes of cochlear implantation (CI) in a group of immigrant deaf children living in a foreign language family, following up to 3 years of a personalized habilitation program compared to age-matched Italian CI recipients. Tests of speech perception ability such as the IT-MAIS, the LiP, the CAP, and speech production such as the MUSS have been used before CI and then after 6 months, 1 year, 2 years, and 3 years. Nonparametrical tests were chosen for comparison. Eight bilingual CI recipients were included in the study and matched to 11 Italian CI recipients. The difference between chronological age at implantation, age at diagnosis, hearing age, and verbal age in the two groups of children was not significant. Comparison of the auditory perceptive and linguistic abilities between the two groups showed significant differences only in preoperative MAIS and postoperative CAP (1 to 3 years). In agreement with other studies, we achieved good performances from bilingual children with CI and our personal experience confirm the attitude of promoting bilingualism throughout the rehabilitation process.

Variability across repeated productions in bilingual children speaking Jamaican Creole and English

PURPOSE

Previous work suggests that variability across repeated productions of the same word may be useful in diagnosing speech sound disorder (SSD) in bilingual children. However, there is debate over what level of variability in transcribed productions should be considered typical even in monolingual speech development. High variability in the input represents a factor that could promote increased production variability in bilinguals. For this reason, the current study examines transcription-based token-to-token variability in bilingual children speaking Jamaican Creole (JC) and English.

METHOD

Twenty-five bilingual children aged 3;4-5;1 and twenty-five monolingual children aged 2;9-4;1 from a previous study were recorded producing eleven items in three repetitions.

RESULT

Contrary to our hypothesis, bilingual children showed similar rates of token-to-token variability compared to the monolingual children. In a separate analysis of bilingual data across languages, bilingual children were more variable in JC compared to English productions.

CONCLUSION

The difference between language contexts suggests that creole languages, which exist on a usage continuum, may be associated with increased variability in production. Our findings suggest that token-to-token production variability may be of similar clinical utility for bilingual and monolingual populations.