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

Hearing aid wear time and its impact on vocabulary in preschoolers with moderately severe to profound hearing loss

OBJECTIVE

This study aimed to explore how the consistency of hearing aid (HA) use impacts vocabulary performance in children with moderately severe to profound hearing loss and determine the amount of HA use time associated with better vocabulary outcomes.

DESIGN

Personal wear time percentage (WTP) was an indicator of HA use consistency, and the information on HA wear time was collected from both parent reports and datalogs. Pearson's correlations were performed to investigate the associations between hearing loss severity, WTP and vocabulary performance. Standard vocabulary scores among children below and above three WTP cutoff values (80%, 85%, and 90%) were examined to determine the WTP amount that yielded significantly better vocabulary outcomes.

STUDY SAMPLE

Forty-seven children aged 36-79 months and their caregivers.

RESULTS

Both parent reports and datalogs WTP significantly correlated with vocabulary outcomes. Parent-reported WTP were found to be predictive of datalogs WTP. Apart from hearing thresholds, HA fitting age and maternal education level, datalogs WTP was a significant independent predictor of vocabulary performance. Children with ≥ 90% WTP were more likely to perform better on vocabulary tests than those with < 90% WTP.

CONCLUSION

The findings support the potential benefits of consistent HA use for vocabulary development.

Cochlear Implant Insertion Routes and Intra-operative Electrophysiological Measurements: A Retrospective Analysis at a Tertiary Care Centre

BACKGROUND

Cochlear implant surgeries are performed by different surgical routes, Round window (RW), Extended round window (Ext RW) and Cochleostomy (C). Optimum intracochlear electrode placement is important to achieve a successful outcome. Intra-operative electrophysiological testing (Impedance and ECAP) is crucial to assess the device function and appropriate electrode placement. The variability of portal of electrode insertion might affect the neural response and its characteristics.

OBJECTIVE

To compare the intraoperative electrophysiological measurements (Impedance and ECAP) for possible differences on auditory nerve stimulation across the three electrode insertion routes.

MATERIALS AND METHODS

This is a retrospective data analysis of 47 cochlear implant recipients at a tertiary care centre in Central India over a period of 4 years. They were broadly divided into two groups depending on the electrode design as full banded and half banded. Intraoperative impedances were recorded for different modes of stimulation and ECAP measured at E5, E10, E15, E20 electrodes in both the groups across the three insertion routes.

RESULTS

In the half-banded group, the impedance values in different modes CG, MP1, MP2, MP1 + 2 did not differ significantly among the surgical routes at all four electrodes. While in the full banded group, for CG mode impedance values at E5 differ significantly. Rest for other modes in full banded group, there was no statistically significant difference across the three routes.

CONCLUSION

The present study supports that there is no statistically significant difference in the intraoperative impedance and ECAP measurements in both, the full-banded and half- banded electrodes across the three surgical routes implying that, all the three surgical approaches provide equal stimulation of the auditory nerve. The CI surgeon can select the electrode insertion portal based on the surgical anatomy, the implant type and individual preferences.

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.

Children's Neural Sensitivity to Prosodic Features of Natural Speech and Its Significance to Speech Development in Cochlear Implanted Children

Catchy utterances, such as proverbs, verses, and nursery rhymes (i.e., "No pain, no gain" in English), contain strong-prosodic (SP) features and are child-friendly in repeating and memorizing; yet the way those prosodic features encoded by neural activity and their influence on speech development in children are still largely unknown. Using functional near-infrared spectroscopy (fNIRS), this study investigated the cortical responses to the perception of natural speech sentences with strong/weak-prosodic (SP/WP) features and evaluated the speech communication ability in 21 pre-lingually deaf children with cochlear implantation (CI) and 25 normal hearing (NH) children. A comprehensive evaluation of speech communication ability was conducted on all the participants to explore the potential correlations between neural activities and children's speech development. The SP information evoked right-lateralized cortical responses across a broad brain network in NH children and facilitated the early integration of linguistic information, highlighting children's neural sensitivity to natural SP sentences. In contrast, children with CI showed significantly weaker cortical activation and characteristic deficits in speech perception with SP features, suggesting hearing loss at the early age of life, causing significantly impaired sensitivity to prosodic features of sentences. Importantly, the level of neural sensitivity to SP sentences was significantly related to the speech behaviors of all children participants. These findings demonstrate the significance of speech prosodic features in children's speech development.

Vocabulary Growth in Mandarin-Speaking Children With Bilateral Cochlear Implants, Bimodal Stimulation, or Unilateral Cochlear Implants During the First Year After Activation

PURPOSE

The purpose of this study was to evaluate vocabulary development in Mandarin-speaking children with bilateral cochlear implants (CIs), bimodal stimulation (CI plus hearing aids [HAs]), or unilateral CIs during the first year after CI activation.

METHOD

Participants included 23 children with simultaneous bilateral CIs, 23 children with bimodal stimulation, and 15 children with unilateral CIs. They all received CIs before 30 months of age. Parents were asked to endorse words that their child could understand only or understand and say using the Early Vocabulary Inventory for Mandarin Chinese at the day of CI activation and 1, 3, 6, 9, and 12 months after CI activation. Receptive and expressive vocabulary sizes were computed.

RESULTS

Growth curve analysis revealed that children with simultaneous bilateral CIs demonstrated faster growth of receptive vocabulary than those with bimodal stimulation, followed by those with unilateral CIs. Moreover, children with simultaneous bilateral CIs reached the 100-word mark for receptive vocabulary earlier than children with bimodal stimulation, followed by those with unilateral CIs. There were no significant differences among the three groups in expressive vocabulary.

CONCLUSIONS

Bilateral CIs have an advantage over bimodal stimulation in early receptive vocabulary development in Mandarin, a tone language. HA usage is still recommended for those who receive one CI.

Early prelingual auditory and language development in children with simultaneous bilateral and unilateral cochlear implants

PURPOSE

This current study aimed to explore early prelingual auditory development (EPLAD) and early language development in Mandarin-speaking children who received simultaneous bilateral cochlear implants (BICI) during the first year of cochlear implantation and compare the performance of the children who received BICI with those received unilateral cochlear implant (UCI).

METHODS

39 Mandarin-speaking children who received BICIs simultaneously and 36 children with UCIs were enrolled in this study. To access the EPLAD, the Infant-Toddler Meaningful Auditory Integration Scale (IT/MAIS) was conducted, and a subtest of the simplified short-form version of the Mandarin Communicative Development Inventory (SSF-MCDI) was used to evaluate the development of expressive and receptive vocabulary for the children at indicated time points after surgery.

RESULTS

In both the simultaneous BICI and UCI groups, we observed significantly increased scores of the SSF-MCDI and IT/MAIS 1 year after the surgery. There are indications of early advantages in children with BICI in IT/MAIS scores (at 1, 3, and 6 months after activation). For early development of language, a great difference between the expressive vocabulary scores and the receptive vocabulary scores was observed in both groups. We found there were not significant differences between the two groups on expressive or receptive vocabulary scores, the use of more differentiated measures might be required in future research. We further found that the development of the receptive or expressive vocabulary is dramatically correlated with the age at implantation and the total scores of IT/MAIS for children with simultaneous BICIs.

CONCLUSION

These results may supplement the skills development of early language and auditory in Mandarin-native children with simultaneous CIs. It is obvious that children with normal hearing have mastery of receptive vocabulary before that of expressive vocabulary, which is the same as children with unilateral and bilateral CIs in this research. IT/MAIS total scores and age at CI were important factors for early language performance in children with simultaneous BICIs.

Can Dual Compression Offer Better Mandarin Speech Intelligibility and Sound Quality Than Fast-Acting Compression?

The aim of this study was to evaluate the efficacy of dual compression for Mandarin-speaking hearing aid users. Dual compression combines fast and slow compressors operating simultaneously across all frequency channels. The study participants were 31 hearing aid users with symmetrical moderate-to-severe hearing loss, with a mean age of 67 years. A new pair of 20-channel behind-the-ear hearing aids (i.e., Phonak Bolero B90-P) was used during the testing. The results revealed a significant improvement in speech reception thresholds in noise when switching from fast-acting compression to dual compression. The sound quality ratings revealed that most listeners preferred dual compression to fast-acting compression for listening effort, listening comfort, speech clarity, and overall sound quality at +4 dB signal-to-noise ratio. These results are consistent with predictions based on the theoretical understanding of dual and fast-acting compression. However, whether these results can be generalized to other languages or other dual compression systems should be verified by future studies.

Early Vocabulary Profiles of Young Deaf Children Who Use Cochlear Implants

Purpose This study examined vocabulary profiles in young cochlear implant (CI) recipients and in children with normal hearing (NH) matched on receptive vocabulary size to improve our understanding of young CI recipients' acquisition of word categories (e.g., common nouns or closed-class words). Method We compared receptive and expressive vocabulary profiles between young CI recipients (n = 48; mean age at activation = 15.61 months, SD = 4.20) and children with NH (n = 48). The two groups were matched on receptive vocabulary size as measured by the MacArthur-Bates Communicative Development Inventories (Fenson et al., 2006): Words and Gestures form. The CI group had, on average, 8.98 months of hearing experience. The mean chronological age at completing the MacArthur-Bates Communicative Development Inventories was 23.99 months (SD = 5.14) for the CI group and 13.72 months (SD = 1.50) for the NH group. Results The CI group had a larger expressive vocabulary size than the receptive vocabulary size-matched NH group. The larger expressive vocabulary size was associated with the group difference in social words but not with common nouns. The analyses for predicate words and closed-class words included only children who produced the target categories. The CI group had a larger proportion of predicate words than the NH group, but no difference was found in closed-class words in expressive vocabulary. Conclusions Differences found in expressive vocabulary profiles may be affected by spoken vocabulary size and their age. A further examination is warranted using language samples to understand the effect of language input on children's vocabulary profiles.

Early auditory skills development in Mandarin speaking children after bilateral cochlear implantation

OBJECTIVES

The purpose of the present study was: (1) to investigate the early auditory preverbal behaviors of infants/toddlers with bilateral cochlear implants (BCI), and to compare their performance with that of unilateral cochlear implant (UCI) peers; (2) to investigate effects of age of implantation, education level of caregivers, living environment, and unaided behavioral threshold before operation on early auditory preverbal development.

METHODS

The evaluation material of the present study was the Mandarin version of the LittlEARS^® Auditory Questionnaire (LEAQ). Assessments were administrated at 0, 1, 2, 3, 6, 9, 12 and 24 months after cochlear implants (CIs) were switched on. A one-way ANOVA was used to analyze the differences of early auditory preverbal performance between each two contiguous test intervals. A two-sample t-test was used to analyze the difference of behaviors between infants/toddlers with BCI and UCI. Non-parametric tests were used to analyze the effects of potential affecting factors on auditory preverbal skills.

RESULTS

Nineteen subjects aging from 9 to 54 months (Mean = 22.7, SD = 13.7) were recruited in the study. At each evaluation time, the average scores of LEAQ were 4.58, 9.00, 16.00, 18.56, 22.00, 31.50, 29.67, and 34.35 respectively. The total score and semantic auditory behavior score increased significantly during the second months after CIs activation (the total score: LSD-t = 3.157, p = 0.030; semantic auditory behavior score: LSD-t = 1.972, p = 0.034). The score of BCI group was significantly higher than UCI group after 1, 3 and 6 months of CI use (1 month: t = 3.257, p = 0.002; 3 months: t = 5.042, p = 0.000; 6 months: t = 4.054, p = 0.000). Education level of caregivers had a positive effect on receptive auditory behavior (H = 6.538, p = 0.035) after CIs switched on for 3 months. The LEAQ performance was not significantly correlated with pre-operative behavioral threshold although they showed a trend of negative correlation in the first 3 months after activation.

CONCLUSION

The study indicated that infants and toddlers who underwent BCI had better auditory preverbal skills than their UCI peers. Higher caregivers' education level positively correlated with the early development of auditory preverbal skills. Better pre-operative behavioral threshold might also benefit early auditory preverbal skills development for BCI children.

Comparable Electrode Impedance and Speech Perception at 12 Months after Cochlear Implantation Using Round Window versus Cochleostomy: An Analysis of 40 Patients

OBJECTIVE

The objective of this study was to examine whether cochlear implantation using the round window (RW) route versus cochleostomy achieves comparable electrode impedance and hearing results.

METHODS

This retrospective analysis included 40 patients receiving a cochlear implant (REZ-1): 20 using the RW approach and the remaining 20 using cochleostomy. Electrode impedance and tone, vowel, consonant, disyllable and sentence perception were measured during and after the implantation.

RESULTS

Electrode impedance did not differ significantly between the 2 groups at any time points [F(1, 38) = 1.84; p = 0.184]: 1.87, 5.16, 6.47 and 6.70 kΩ in the RW group versus 2.86, 5.33, 6.92 and 8.16 kΩ in the cochleostomy group at 0, 1, 3 and 12 months, respectively. There was no significant difference between the RW and cochleostomy groups for tone (77.50 vs. 80.50%; p = 0.472), vowel (77.70 vs. 78.65%; p = 0.760), consonant (75.50 vs. 78.25%; p = 0.443), disyllable (78.60 vs. 81.50%; p = 0.317) and sentence (50.90 vs. 52.50%; p = 0.684) perception at 12 months.

CONCLUSION

The RW approach is comparable to cochleostomy in electrode placement as reflected by impedance and function as reflected by tone, vowel, consonant, disyllable and sentence perception.