Weighting of Acoustic Cues to a Manner Distinction by Children With and Without Hearing Loss

The impact of spectral and temporal processing on speech recognition in children with cochlear implants

While the relationships between spectral resolution, temporal resolution, and speech recognition are well defined in adults with cochlear implants (CIs), they are not well defined for prelingually deafened children with CIs, for whom language development is ongoing. This cross-sectional study aimed to better characterize these relationships in a large cohort of prelingually deafened children with CIs (N = 47; mean age = 8.33 years) by comprehensively measuring spectral resolution thresholds (measured via spectral modulation detection), temporal resolution thresholds (measured via sinusoidal amplitude modulation detection), and speech recognition (measured via monosyllabic word recognition, vowel recognition, and sentence recognition in noise via both fixed signal-to-noise ratio (SNR) and adaptively varied SNR). Results indicated that neither spectral or temporal resolution were significantly correlated with speech recognition in quiet or noise for children with CIs. Both age and CI experience had a moderate effect on spectral resolution, with significant effects for spectral modulation detection at a modulation rate of 0.5 cyc/oct, suggesting spectral resolution may improve with maturation. Thus, it is possible we may see an emerging relationship between spectral resolution and speech perception over time for children with CIs. While further investigation into this relationship is warranted, these findings demonstrate the need for new investigations to uncover ways of improving spectral resolution for children with CIs.

Phonological Awareness and Working Memory in Mandarin-Speaking Preschool-Aged Children With Cochlear Implants

PURPOSE

Cochlear implants (CIs) provide significant benefits for profoundly deaf children in their language and cognitive development. However, it remains unclear whether Mandarin-speaking young children with early implantation can develop age-equivalent phonological awareness (PA) skill and working memory (WM) capacity as their normal hearing (NH) peers. The aim of this study was to investigate PA and WM in preschool-aged children with or without hearing loss and to examine the relationship between the two basic skills.

METHOD

The data were collected from 16 Mandarin-speaking preschoolers with CIs and 16 age-matched children with NH. All preschool participants were instructed to complete four phonological detection tasks and four digit span tasks. Linear mixed-effects modeling was performed to evaluate PA and WM performances between two groups across different tasks.

RESULTS

CI preschoolers showed comparable performances on par with NH controls in phonological detections and visual digit spans. In addition, Pearson correlation analysis revealed a positive relationship between phonological detections and auditory digit spans in preschool-aged children with CIs.

CONCLUSION

With early implantation, the congenitally deaf children were capable of developing age-appropriate PA skill and WM capacity, which have practical implications for aural rehabilitation in this special pediatric population.

Speech, language, and literacy outcomes for children with mild to moderate hearing loss: A systematic review

PURPOSE

To systematically review the current literature to describe the speech, language, and literacy skills of children with mild to moderate hearing loss (MMHL).

METHOD

Systematic searching of seven online databases identified 13 eligible studies examining speech, language, and literacy outcomes for children with MMHL. Studies were rated for quality. Findings were reported via narrative synthesis.

RESULTS

Many studies reported no significant differences between children with MMHL and hearing peers on speech, language, and literacy measures. Studies that did report significant differences reported that children with MMHL performed significantly more poorly than hearing peers in speech production, receptive morphology, following directions, recalling sentences, expressive morphology, and word and non-word reading.

CONCLUSIONS

Due to the heterogeneity in participant characteristics, moderating factors reported, and measures used, clear patterns in the outcomes were difficult to find. Further research into speech, language and literacy outcomes for children with MMHL from early childhood to adolescence (longitudinal studies) are required to describe possible trajectories for children with MMHL including how moderating factors (such as age of hearing aid fitting, duration of use, and access to early intervention) may be contributing to these trajectories.

Spectral Resolution Development in Children With Normal Hearing and With Cochlear Implants: A Review of Behavioral Studies

PURPOSE

This review article provides a theoretical overview of the development of spectral resolution in children with normal hearing (cNH) and in those who use cochlear implants (CIs), with an emphasis on methodological considerations. The aim was to identify key directions for future research on spectral resolution development in children with CIs.

METHOD

A comprehensive literature review was conducted to summarize and synthesize previously published behavioral research on spectral resolution development in normal and impaired auditory systems.

CONCLUSIONS

In cNH, performance on spectral resolution tasks continues to improve through the teenage years and is likely driven by gradual maturation of across-channel intensity resolution. A small but growing body of evidence from children with CIs suggests a more complex relationship between spectral resolution development, patient demographics, and the quality of the CI electrode-neuron interface. Future research should aim to distinguish between the effects of patient-specific variables and the underlying physiology on spectral resolution abilities in children of all ages who are hard of hearing and use auditory prostheses.

Parental Language Input to Children With Hearing Loss: Does It Matter in the End?

Purpose Parental language input (PLI) has reliably been found to influence child language development for children at risk of language delay, but previous work has generally restricted observations to the preschool years. The current study examined whether PLI during the early years explains variability in the spoken language abilities of children with hearing loss at those young ages, as well as later in childhood. Participants One hundred children participated: 34 with normal hearing, 24 with moderate losses who used hearing aids (HAs), and 42 with severe-to-profound losses who used cochlear implants (CIs). Mean socioeconomic status was middle class for all groups. Children with CIs generally received them early. Method Samples of parent-child interactions were analyzed to characterize PLI during the preschool years. Child language abilities (CLAs) were assessed at 48 months and 10 years of age. Results No differences were observed across groups in how parents interacted with their children. Nonetheless, strong differences across groups were observed in the effects of PLI on CLAs at 48 months of age: Children with normal hearing were largely resilient to their parents' language styles. Children with HAs were most influenced by the amount of PLI. Children with CIs were most influenced by PLI that evoked child language and modeled more complex versions. When potential influences of preschool PLI on CLAs at 10 years of age were examined, those effects at preschool were replicated. When mediation analyses were performed, however, it was found that the influences of preschool PLI on CLAs at 10 years of age were partially mediated by CLAs at preschool. Conclusion PLI is critical to the long-term spoken language abilities of children with hearing loss, but the style of input that is most effective varies depending on the severity of risk for delay.

Patterns of recognition of Arabic consonants by non-native children with cochlear implants and normal hearing

OBJECTIVE

This study examined the patterns of recognition of Arabic consonants, via information transmission analysis for phonological features, in a group of Malay children with normal hearing (NH) and cochlear implants (CI).

METHOD

A total of 336 and 616 acoustic tokens were collected from six CI and 11 NH Malay children, respectively. The groups were matched for hearing age and duration of exposure to Arabic sounds. All the 28 Arabic consonants in the form of consonant-vowel /a/ were presented randomly twice via a loudspeaker at approximately 65 dB SPL. The participants were asked to repeat verbally the stimulus heard in each presentation.

RESULTS

Within the native Malay perceptual space, the two groups responded differently to the Arabic consonants. The dispersed uncategorized assimilation in the CI group was distinct in the confusion matrix (CM), as compared to the NH children. Consonants /ħ/, /tˁ/, /sˁ/ and /ʁ/ were difficult for the CI children, while the most accurate item was /k/ (84%). The CI group transmitted significantly reduced information, especially for place feature transmission, then the NH group (p < 0.001). Significant interactions between place-hearing status and manner-hearing status were also obtained, suggesting there were information transmission differences in the pattern of consonants recognition between the study groups.

CONCLUSION

CI and NH Malay children may be using different acoustic cues to recognize Arabic sounds, which contribute to the different assimilation categories' patterns within the Malay perceptual space.

Verbal Working Memory in Children With Cochlear Implants

PURPOSE

Verbal working memory in children with cochlear implants and children with normal hearing was examined.

PARTICIPANTS

Ninety-three fourth graders (47 with normal hearing, 46 with cochlear implants) participated, all of whom were in a longitudinal study and had working memory assessed 2 years earlier.

METHOD

A dual-component model of working memory was adopted, and a serial recall task measured storage and processing. Potential predictor variables were phonological awareness, vocabulary knowledge, nonverbal IQ, and several treatment variables. Potential dependent functions were literacy, expressive language, and speech-in-noise recognition.

RESULTS

Children with cochlear implants showed deficits in storage and processing, similar in size to those at second grade. Predictors of verbal working memory differed across groups: Phonological awareness explained the most variance in children with normal hearing; vocabulary explained the most variance in children with cochlear implants. Treatment variables explained little of the variance. Where potentially dependent functions were concerned, verbal working memory accounted for little variance once the variance explained by other predictors was removed.

CONCLUSIONS

The verbal working memory deficits of children with cochlear implants arise due to signal degradation, which limits their abilities to acquire phonological awareness. That hinders their abilities to store items using a phonological code.