Early speech perception in Mandarin-speaking children at one-year post cochlear implantation

Tone perception development in Mandarin-speaking children with cochlear implants

OBJECTIVE

The purpose of this study was to examine the longer-term effects of cochlear implant (CI) use on tone perception by evaluating improvement in Mandarin tone recognition in children with CIs 2 and 3 years post CI activation, and to explore the effects of implant age, chronological age and duration of CI use on the development of tone perception.

METHODS

Tone perception was assessed in 29 bilateral profound hearing impaired children (mean chronological age = 4.6 years, SD = 0.7 years) with unilateral CIs at 24 and 36 months after CI activation using the tone perception subtest in the Mandarin Early Speech Perception (MESP-T) test.

RESULTS

Children's tone recognition for tone pairs and individual tones improved significantly between 2 and 3 years post CI use, showing an increase in average tone recognition score from 73.2% to 81.8%, which was significantly higher than chance level (i.e. 50%). There was no significant correlation between tone recognition ability and either implant age or chronological age at two evaluation points. Further analysis revealed that the tone recognition score for tone pair 2-3 was significantly lower than that for other tone pairs except for tone pair 2-4.

CONCLUSIONS

Longer CI experience can significantly improve tone recognition ability in CI children between 2 and 3 years post CI activation.

Characteristics of Early Expressive Vocabulary in Mandarin-Speaking Children With Cochlear Implants

PURPOSE

The aim of this study is to evaluate whether Mandarin-speaking children with cochlear implants (CIs) demonstrated early lexical composition similar to their hearing peers who were at the same vocabulary level and the extent to which children with CIs were sensitive to linguistic and conceptual properties when developing early lexicon.

METHOD

Participants were 77 Mandarin-speaking children with CIs who received CIs before 30 months of age. Their expressive vocabulary was documented using the Infant Checklist of the Early Vocabulary Inventory for Mandarin Chinese 9 or 12 months after CI activation. Percent social words, common nouns, predicates (verbs, adjectives), and closed-class words in total vocabulary were computed for children at different vocabulary levels. Common nouns and verbs were further coded for their word class (noun, verb), word frequency, word length, and imageability to predict how likely a given noun or verb would be produced by children with CIs.

RESULTS

Like children with typical hearing, social words were the most dominant category when vocabulary size in children with CIs was smaller than 20 words; common nouns became the most dominant category when the vocabulary size reached 21 words. The difference in percent common nouns and percent predicates (i.e., noun bias) was similar in children with CIs and their hearing peers. In addition, verbs, common words, monosyllabic words, and more imageable words were more likely to be produced by children with CIs than their counterparts.

CONCLUSIONS

Mandarin children with CIs showed language-specific patterns in early lexical composition like their hearing peers. They were able to use multiple linguistic and conceptual cues when approaching early expressive vocabulary despite perceptual and processing constraints.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21357723.

Sociodemographic disparities in pediatric cochlear implantation outcomes: A systematic review

OBJECTIVES

To determine the impact of sociodemographic factors on post-operative performance outcomes among PCI recipients across the world.

METHODS

A qualitative systematic review of PubMed, Scopus, Web of Science, and Embase was undertaken for studies analyzing the association of sociodemographic factors with measures of PCI outcomes published before July 18, 2021. Study quality assessment tools from the National Institutes of Health (NIH) were used to assess for risk of bias.

RESULTS

Out of 887 unique abstracts initially retrieved, 45 papers were included in the final qualitative systematic review. Sociodemographic disparities in PCI outcomes from 4702 PCI recipients were studied in 19 countries, with 14 studies conducted in the United States of America, published within the years of 1999 to 2021. Parental education and socioeconomic status (e.g. income) were the most investigated disparities in PCI outcomes with 24 and 17 identified studies, respectively.

CONCLUSION

Socioeconomic status was a consistently reported determinant of PCI outcomes in the USA and elsewhere, and parental education, the most reported disparity, consistently impacted outcomes in countries outside the USA. This study is limited by our inability to perform a meta-analysis given the lack of standardization across measures of sociodemographic variables and assessment measures for PCI outcomes. Future studies should address the literature gap on racial and ethnic disparities among PCI outcomes and use standardized measures for sociodemographic variables and PCI outcomes to facilitate meta-analyses on the topic. Targeting the mechanisms of these disparities may mitigate the impact of the sociodemographic factors on PCI outcomes.

A Review of Speech Perception of Mandarin-Speaking Children With Cochlear Implantation

Objective: This paper reviewed the literature on the development of and factors affecting speech perception of Mandarin-speaking children with cochlear implantation (CI). We also summarized speech outcome measures in standard Mandarin for evaluating auditory and speech perception of children with CI.

Method: A comprehensive search of Google Scholar and PubMed was conducted from March to June 2021. Search terms used were speech perception/lexical tone recognition/auditory perception AND cochlear implant AND Mandarin/Chinese.

Conclusion: Unilateral CI recipients demonstrated continuous improvements in auditory and speech perception for several years post-activation. Younger age at implantation and longer duration of CI use contribute to better speech perception. Having undergone a hearing aid trial before implantation and having caregivers whose educational level is higher may lead to better performance. While the findings that support the use of CI to improve speech perception continue to grow, much research is needed to validate the use of unilateral and bilateral implantation. Evidence to date, however, revealed bimodal benefits over CI-only conditions in lexical tone recognition and sentence perception in noise. Due to scarcity of research, conclusions on the benefits of bilateral CIs compared to unilateral CI or bimodal CI use cannot be drawn. Therefore, future research on bimodal and bilateral CIs is needed to guide evidence-based clinical practice.

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.

Effects of Fundamental Frequency Contours on Sentence Recognition in Mandarin-Speaking Children With Cochlear Implants

Purpose Fundamental frequency (F0) is the primary acoustic cue for lexical tone perception in tonal languages but is processed in a limited way in cochlear implant (CI) systems. The aim of this study was to evaluate the importance of F0 contours in sentence recognition in Mandarin-speaking children with CIs and find out whether it is similar to/different from that in age-matched normal-hearing (NH) peers. Method Age-appropriate sentences, with F0 contours manipulated to be either natural or flattened, were randomly presented to preschool children with CIs and their age-matched peers with NH under three test conditions: in quiet, in white noise, and with competing sentences at 0 dB signal-to-noise ratio. Results The neutralization of F0 contours resulted in a significant reduction in sentence recognition. While this was seen only in noise conditions among NH children, it was observed throughout all test conditions among children with CIs. Moreover, the F0 contour-induced accuracy reduction ratios (i.e., the reduction in sentence recognition resulting from the neutralization of F0 contours compared to the normal F0 condition) were significantly greater in children with CIs than in NH children in all test conditions. Conclusions F0 contours play a major role in sentence recognition in both quiet and noise among pediatric implantees, and the contribution of the F0 contour is even more salient than that in age-matched NH children. These results also suggest that there may be differences between children with CIs and NH children in how F0 contours are processed.

Analysis of the developmental trajectory and influencing factors of auditory and speech functions after cochlear implantation in Mandarin Chinese speaking children

Background: The auditory and speech development of the children with cochlear implants (CIs) are influenced by many factors.Objective: To study the developmental trajectory and influencing factors of auditory and speech functions for the Mandarin Chinese speaking children with CIs.Material and methods: The children with CIs undergoing rehabilitation in the same institution from June 2016 to June 2019 were followed up. Their closed monosyllables and disyllables recognition rate, closed average language age, categories of auditory performance (CAP) and speech intelligibility rating (SIR) were evaluated at 0, 1, 3, 6, 12 and 24 months of rehabilitation. The results were analyzed by SPSS 23.0.Results: 49 children were followed up for 1 year, 29 children for 2 years. The evaluated indicators of auditory and speech functions were improved with the prolongation of rehabilitation and influenced by the age of cochlear implantation, the use of hearing aids before surgery, guardian's educational degree, the relationship between guardian and child.Conclusions and significance: The auditory and speech functions of the children with CIs were improved significantly with the prolongation of rehabilitation and influenced by many factors, which can help us to predict the effect of CI more accurately and develop an individualized rehabilitation program.

Trajectory of auditory and language development in the early stages of pre-lingual children post cochlear implantation: A longitudinal follow up study

OBJECTIVES

The aim of this longitudinal follow-up study was to explore the trajectories of early auditory and language development in Mandarin speaking children younger than 3 years of age following switch-on of their cochlear implants (CIs).

METHODS

Early auditory and language development was measured longitudinally using the Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS), which is a commonly used tool for assessing early prelingual auditory development (EPLAD) in children, and the subtest (Words and Gestures, W&G) of the simplified short form version of the Mandarin Communicative Development Inventory (SSF-MCDI) to assess receptive and expressive vocabulary growths of children in 24 pediatric cochlea implant recipients at baseline, 3, 6, and 12 months following switch-on. Age at switch-on ranged from 1 to 3 years of age. Participants were divided into two groups based on age at switch-on. The IT-MAIS and SSF-MCDI (W&G) scores were analyzed with comparison to normal children, unaided hearing-impaired children, and CI children.

RESULTS

Significant improvements in IT-MAIS and SSF-MCDI (W&G) scores from baseline to 12 months were seen after switch-on in both CI groups and were comparable to the normal hearing children in the first year of age. The IT-MAIS scores of CI children in both groups at 12 months after switch-on surpassed the average level of unaided peers with profound hearing loss and were similar to the average level of unaided peers with mild hearing loss. SSF-MCDI (W&G) scores in word comprehension and expression were significantly different between groups at some intervals.

CONCLUSIONS

Children younger than 3 years of age with cochlear implants have similar trajectories in early auditory and language developments to normally hearing children. Moreover, early implantation is an important factor for the early auditory development when comparing EPLAD results between CI children and unaided peers with different hearing loss. Finally, it is noteworthy that CI children master the skill of word comprehension before the skill of word expression, and that word comprehension may be the basis of word expression.

Cochlear Implantation and Rehabilitation

Cochlear implant (CI) is currently the only medical treatment available to partially restore hearing to patients with profound-to-severe hearing loss. CI is fundamentally distinct from hearing aid (HA) use, as implants are surgically placed under the skin behind the ear where they bypass the normal sound-conducting mechanism, convert sound signals into electrical stimulation, and directly stimulate the residual auditory nerves. In recent years, CI has evolved into one of the most profound advances in modern medicine and provided hearing to more than 320,000 deaf patients. According to the time of onset, deafness is classified as prelingual and postlingual deafness, and the indications of cochlear implants vary slightly. The medical evaluation must be made before surgery, including the medical history, objective and subjective audiometry, imaging of the ear, as well as the genetic diagnostic. Here we reviewed the surgical approaches for cochlear implants as well as the complications.

Mandarin-Speaking, Kindergarten-Aged Children With Cochlear Implants Benefit From Natural F 0 Patterns in the Use of Semantic Context During Speech Recognition

PURPOSE

The purpose of this study was to investigate the extent to which semantic context and F0 contours affect speech recognition by Mandarin-speaking, kindergarten-aged children with cochlear implants (CIs).

METHOD

The experimental design manipulated two factors, that is, semantic context, by comparing the intelligibility of normal sentence versus word list, and F0 contours, by comparing the intelligibility of utterances with natural versus flat F0 patterns. Twenty-two children with CIs completed a speech recognition test.

RESULTS

Children with CIs could use both semantic context and F0 contours to assist speech recognition. Furthermore, natural F0 patterns provided extra benefit when semantic context was present than when it was absent.

CONCLUSION

Dynamic F0 contours play an important role in speech recognition by Mandarin-speaking children with CIs despite the well-known limitation of CI devices in extracting F0 information.

Vocabulary development in Mandarin-speaking children with cochlear implants and its relationship with speech perception abilities

BACKGROUND

China has the largest population of children with hearing impairments and cochlear implantation is gaining popularity there. However, the vocabulary development in this population is largely unexplored.

AIMS

This study examined early vocabulary outcomes, factors influencing early vocabulary development and the relationship between speech perception and vocabulary development in Mandarin-speaking children during the first year of cochlear implant use.

METHODS AND PROCEDURES

A battery of vocabulary tests was administered to 80 children before implantation and 3, 6, and 12 months after implantation. Demographic information was obtained to evaluate their relationships with vocabulary outcomes.

OUTCOMES AND RESULTS

The Mandarin-speaking children, who received their cochlear implants before 3 years of age, developed vocabulary at a rate faster than that of their same-aged peers with normal hearing. Better pre-implant hearing levels, younger age at implantation, and higher maternal education level contributed to the early vocabulary development. The trajectories of speech perception development highly correlated with those of vocabulary development during 3 to 12 months of CI use.

CONCLUSIONS

and Implications: These findings imply that the vocabulary development of children implanted before 3 years of age may catch up with that of their hearing peers.

Current trends in outcome studies for children with hearing loss and the need to establish a comprehensive framework of measuring outcomes in children with hearing loss in China

Since the 1970s, outcome studies for children with hearing loss expanded from focusing on assessing auditory awareness and speech perception skills to evaluating language and speech development. Since the early 2000s, the multi-center large scale research systematically studied outcomes in the areas of auditory awareness, speech-perception, language development, speech development, educational achievements, cognitive development, and psychosocial development. These studies advocated the establishment of baseline and regular follow-up evaluations with a comprehensive framework centered on language development. Recent research interests also include understanding the vast differences in outcomes for children with hearing loss, understanding the relationships between neurocognitive development and language acquisition in children with hearing loss, and using outcome studies to guide evidence-based clinical practice. After the establishment of standardized Mandarin language assessments, outcomes research in Mainland China has the potential to expand beyond auditory awareness and speech perception studies.