A comparison of vowel productions in prelingually deaf children using cochlear implants, severe hearing-impaired children using conventional hearing aids and normal-hearing children

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.

Effect of telepractice on pediatric cochlear implant users and provider vowel space: A preliminary report

Clear speaking styles are goal-oriented modifications in which talkers adapt acoustic-phonetic characteristics of speech to compensate for communication challenges. Do children with hearing loss and a clinical provider modify speech characteristics during telepractice to adjust for remote communication? The study examined the effect of telepractice (tele-) on vowel production in seven (mean age 4:11 years, SD 1:2 years) children with cochlear implants (CIs) and a provider. The first (F1) and second (F2) formant frequencies of /i/, /ɑ/, and /u/ vowels were measured in child and provider speech during one in-person and one tele-speech-language intervention, order counterbalanced. Child and provider vowel space areas (VSA) were calculated. The results demonstrated an increase in F2 formant frequency for /i/ vowel in child and provider speech and an increase in F1 formant frequency for /ɑ/ vowel in the provider speech during tele- compared to in-person intervention. An expansion of VSA was found in child and provider speech in tele- compared to in-person intervention. In children, the earlier age of CI activation was associated with larger VSA in both tele- and in-person intervention. The results suggest that the children and the provider adjust vowel articulation in response to remote communication during telepractice.

What Acoustic Studies Tell Us About Vowels in Developing and Disordered Speech

Purpose Literature was reviewed on the development of vowels in children's speech and on vowel disorders in children and adults, with an emphasis on studies using acoustic methods. Method Searches were conducted with PubMed/MEDLINE, Google Scholar, CINAHL, HighWire Press, and legacy sources in retrieved articles. The primary search items included, but were not limited to, vowels, vowel development, vowel disorders, vowel formants, vowel therapy, vowel inherent spectral change, speech rhythm, and prosody. Results/Discussion The main conclusions reached in this review are that vowels are (a) important to speech intelligibility; (b) intrinsically dynamic; (c) refined in both perceptual and productive aspects beyond the age typically given for their phonetic mastery; (d) produced to compensate for articulatory and auditory perturbations; (e) influenced by language and dialect even in early childhood; (f) affected by a variety of speech, language, and hearing disorders in children and adults; (g) inadequately assessed by standardized articulation tests; and (h) characterized by at least three factors-articulatory configuration, extrinsic and intrinsic regulation of duration, and role in speech rhythm and prosody. Also discussed are stages in typical vowel ontogeny, acoustic characterization of rhotic vowels, a sensory-motor perspective on vowel production, and implications for clinical assessment of vowels.

Rating the overall speech quality of hearing-impaired children by means of comparative judgements

OBJECTIVE

Acoustic measurements have shown that the speech of hearing-impaired (HI) children deviates from the speech of normally hearing (NH) peers. The aim of the present study is to examine whether listeners with varying degrees of experience with (HI) children's speech perceive a difference in the overall speech quality of seven-year-old NH children and their HI peers who received a device before the age of two.

METHOD

Short speech samples of seven children with NH, seven children with an acoustic hearing aid (HA) and seven children with a cochlear implant (CI) were judged by three groups of listeners (audiologists, primary school teachers and inexperienced listeners) in a comparative judgement task. In this task, listeners compared stimuli in pairs and decided which stimulus sounded better, leading to a ranking of the stimuli according to their overall speech quality.

RESULTS

The ranking showed that the overall speech quality differed considerably for HI and NH children. The latter group had a significantly higher overall speech quality than HI children. In the group of HI children, children with CI were ranked higher than children with HA. Moreover, length of device use was found to have a significant effect in the group of children with CI: longer device experience led to better ratings. This effect was significantly less strong in HA children. No significant differences were found between the three groups of listeners.

CONCLUSION

Listeners agree that the speech of NH children sounds better than the speech of HI children. This result indicates that even after almost seven years of device use, the speech of HI children still differs from the speech of NH children. The overall speech quality of CI children was better than that of HA children, and this effect increased with longer device use. No effect of listeners' experience with (NH and/or HI) children's speech was established.

Development and validation of the protocol for the evaluation of voice in patients with hearing impairment (PEV-SHI)

Introduction

The voice of individuals with hearing impairment has been widely described, and can be compromised in all levels of the phonatory system.

Objective

To develop and validate an instrument for evaluating the voice of this population.

Methods

The instrument underwent the validation steps suggested by the Scientific Advisory Committee of the Medical Outcomes Trust. The study sample consisted of seventy-eight Brazilian people with cochlear implants (experimental group) and 78 individuals with normal hearing (control group), divided in groups by age range — children from 3 to 5 years; children from 6 to 10 years and adults from 18 to 46 years. The study sample participated in a voice recording of the sustained vowel /a/, connected speech and spontaneous conversation, in which three voice specialists rated using the proposed instrument. It consists of visual-analog scales of suprasegmental aspects, respiratory-phonatory coordination, resonance, phonation, additional parameters and general vocal perception.

Results

Evaluation by an expert committee and a pilot test established content validity. Reliability measures showed excellent test-retest reproducibility for the majority of the parameters. Analysis with the ROC curve showed that perceptual evaluation with the sustained vowel did not strongly differentiate individuals with cochlear implants from those with normal hearing, and the parameter “speech rate” did not differentiate the groups at all. For the connected speech and spontaneous conversation, the majority of the parameters differentiated the experimental group from the control group with an area under the curve ≥0.7. The cutoff values with maximum specificity and sensitivity were 30.5 for mild, 49.0 for moderate and 69.5 for intense deviation.

Conclusions

The protocol for the evaluation of voice in subjects with hearing impairment, PEV-SHI, is a reliable and useful tool for assessing the particularities of the voice of individuals with hearing impairment treated with cochlear implants and can be used in research and clinical settings to standardize evaluation and facilitate information exchange among services.

Temporal characteristics of stop consonants in pediatric cochlear implant users

Objectives: The benefits of Cochlear Implant (CI) in improving speech production abilities in children with hearing impairment can be reflected through acoustic analysis. The primary aim of the study was to investigate the temporal characteristics of stop consonants in Malayalam speaking children using CI. Methods: Twelve children using CI and 12 age- and gender-matched typically developing children (TDC) participated in the study. Simple bisyllabic words with selected target consonants were elicited through a picture naming task and were recorded. Acoustic analysis was carried out using Praat software to derive the acoustic measures - Voice Onset Time (VOT), Burst duration and Closure duration. Results: The results of the study revealed that children using CI differed significantly from TDC for a few target consonants in burst duration and closure duration. However, VOT did not show any significant difference between children using CI and TDC. Conclusion: With early implantation and intensive speech intervention, there is a significant improvement in the speech of children using CI. Yet may have minor deficits which could impact the naturalness of speech. The study highlights the importance of acoustic analyses in identifying these speech errors at a finer level and utilizing the same to evaluate intervention efficacy.

Perception-Production Links in Children's Speech

Purpose Child phonologists have long been interested in how tightly speech input constrains the speech production capacities of young children, and the question acquires clinical significance when children with hearing loss are considered. Children with sensorineural hearing loss often show differences in the spectral and temporal structures of their speech production, compared to children with normal hearing. The current study was designed to investigate the extent to which this problem can be explained by signal degradation. Method Ten 5-year-olds with normal hearing were recorded imitating 120 three-syllable nonwords presented in unprocessed form and as noise-vocoded signals. Target segments consisted of fricatives, stops, and vowels. Several measures were made: 2 duration measures (voice onset time and fricative length) and 4 spectral measures involving 2 segments (1st and 3rd moments of fricatives and 1st and 2nd formant frequencies for the point vowels). Results All spectral measures were affected by signal degradation, with vowel production showing the largest effects. Although a change in voice onset time was observed with vocoded signals for /d/, voicing category was not affected. Fricative duration remained constant. Conclusions Results support the hypothesis that quality of the input signal constrains the speech production capacities of young children. Consequently, it can be concluded that the production problems of children with hearing loss-including those with cochlear implants-can be explained to some extent by the degradation in the signal they hear. However, experience with both speech perception and production likely plays a role as well.

Basic Measures of Prosody in Spontaneous Speech of Children With Early and Late Cochlear Implantation

PURPOSE

Relative to normally hearing (NH) peers, the speech of children with cochlear implants (CIs) has been found to have deviations such as a high fundamental frequency, elevated jitter and shimmer, and inadequate intonation. However, two important dimensions of prosody (temporal and spectral) have not been systematically investigated. Given that, in general, the resolution in CI hearing is best for the temporal dimension and worst for the spectral dimension, we expected this hierarchy to be reflected in the amount of CI speech's deviation from NH speech. Deviations, however, were expected to diminish with increasing device experience.

METHOD

Of 9 Dutch early- and late-implanted (division at 2 years of age) children and 12 hearing age-matched NH controls, spontaneous speech was recorded at 18, 24, and 30 months after implantation (CI) or birth (NH). Six spectral and temporal outcome measures were compared between groups, sessions, and genders.

RESULTS

On most measures, interactions of Group and/or Gender with Session were significant. For CI recipients as compared with controls, performance on temporal measures was not in general more deviant than spectral measures, although differences were found for individual measures. The late-implanted group had a tendency to be closer to the NH group than the early-implanted group. Groups converged over time.

CONCLUSIONS

Results did not support the phonetic dimension hierarchy hypothesis, suggesting that the appropriateness of the production of basic prosodic measures does not depend on auditory resolution. Rather, it seems to depend on the amount of control necessary for speech production.

Can listeners hear the difference between children with normal hearing and children with a hearing impairment?

Acoustic measurements have shown that the speech of hearing-impaired (HI) children differs from that of normally hearing (NH) children, even after several years of device use. This study focuses on the perception of HI speech in comparison to NH children's speech. The purpose of this study was to investigate whether adult listeners can identify the speech of NH and HI children. Moreover, it is studied whether listeners' experience and the children's length of device use play a role in that assessment. For this study, short utterances of 7 children with a cochlear implant (CI), 7 children with an acoustic hearing aid (HA) and 7 children with NH were presented to 90 listeners who were required to specify the hearing status of each speech sample. The judges had different degrees of familiarity with hearing disorders: there were 30 audiologists, 30 primary schoolteachers and 30 inexperienced listeners. The results show that the speech of children with NH and HI can reliably be identified. However, listeners do not manage to distinguish between children with CI and HA. Children with CI are increasingly identified as NH with increasing length of device use. For children with HA, there is no similar change with longer device use. Also, experienced listeners seem to display a more lenient attitude towards atypical speech, whereas inexperienced listeners are stricter and generally consider more utterances to be produced by children with HI.

Vowel production in hearing impaired children: A comparison between normal-hearing, hearing-aided and cochlear-implanted children

INTRODUCTION AND OBJECTIVES

Inadequate auditory feedback in prelingually deaf children alters the articulation of consonants and vowels. The purpose of this investigation was to compare vowel production in Spanish-speaking deaf children with cochlear implantation, and with hearing-aids with normal-hearing children by means of acoustic analysis of formant frequencies and vowel space.

METHODS

A total of 56 prelingually deaf children (25 with cochlear implants and 31 wearing hearing-aids) and 47 normal-hearing children participated. The first 2 formants (F1 and F2) of the five Spanish vowels were measured using Praat software. One-way analysis of variance (ANOVA) and post hoc Scheffé test were applied to analyze the differences between the 3 groups. The surface area of the vowel space was also calculated.

RESULTS

The mean value of F1 in all vowels was not significantly different between the 3 groups. For vowels /i/, /o/ and /u/, the mean value of F2 was significantly different between the 2 groups of deaf children and their normal-hearing peers.

CONCLUSION

Both prelingually hearing-impaired groups tended toward subtle deviations in the articulation of vowels that could be analyzed using an objective acoustic analysis programme.

Acoustic and kinematic analyses of Mandarin vowels in speakers with hearing impairment

The central aim of this experiment was to compare acoustic parameters, formant frequencies and vowel space area (VSA), in adolescents with hearing-impaired (HI) and their normal-hearing (NH) peers; for kinematic parameters, the movements of vocal organs, especially the lips, jaw and tongue, during vowel production were analysed. The participants were 12 adolescents with different degrees of hearing impairment. The control group consisted of 12 age-matched NH adolescents. All participants were native Chinese speakers who were asked to produce the Mandarin vowels /a/, /i/ and /u/, with subsequent acoustic and kinematic analysis. There was significant difference between the two groups. Additionally, the HI group produced more exaggerated mouth and less tongue movements in all vowels, compared to their NH peers. Results were discussed regarding possible relationship between acoustic data, articulatory movements and degree of hearing loss to provide an integrative assessment of acoustic and kinematic characteristics of individuals with hearing loss.

Acoustic Analysis of Persian Vowels in Cochlear Implant Users: A Comparison With Hearing-impaired Children Using Hearing Aid and Normal-hearing Children

OBJECTIVE

Vowel production in essence is auditorily controlled; hence, the role of the auditory feedback in vowel production is very important. The purpose of this study was to compare formant frequencies and vowel space in Persian-speaking deaf children with cochlear implantation (CI), hearing-impaired children with hearing aid (HA), and their normal-hearing (NH) peers.

METHODS

A total of 40 prelingually children with hearing impairment and 20 NH groups participated in this study. Participants were native Persian speakers. The average of first formant frequency (F₁) and second formant frequency (F₂) of the six vowels were measured using Praat software (version 5.1.44). One-way analysis of variance (ANOVA) was used to analyze the differences between the three3 groups.

RESULTS

The mean value of F₁ for vowel /i/ was significantly different (between CI and NH children and also between HA and NH groups) (F_{2, 57} = 9.229, P < 0.001). For vowel /a/, the mean value of F₁ was significantly different (between HA and NH groups) (F_{2, 57} = 3.707, P < 0.05). Regarding the second formant frequency, a post hoc Tukey test revealed that the differences were between HA and NH children (P < 0.05). F₂ for vowel /o/ was significantly different (F_{2, 57} = 4.572, P < 0.05). Also, the mean value of F₂ for vowel /a/ was significantly different (F_{2, 57} = 3.184, P < 0.05).

CONCLUSION

About 1 year after implantation, the formants shift closer to those of the NH listeners who tend to have more expanded vowel spaces than hearing-impaired listeners with hearing aids. Probably, this condition is because CI has a subtly positive impact on the place of articulation of vowels.

Hearing impairment and vowel production. A comparison between normally hearing, hearing-aided and cochlear implanted Dutch children

This study investigated the acoustic characteristics of the Belgian Standard Dutch vowels in children with hearing impairment and in children with normal hearing. In a balanced experimental design, the 12 vowels of Belgian Standard Dutch were recorded in three groups of children: a group of children with normal hearing, a group with a conventional hearing aid and a group with a cochlear implant. The formants, the surface area of the vowel space and the acoustic differentiation between the vowels were determined. The analyses revealed that many of the vowels in hearing-impaired children showed a reduction of the formant values. This reduction was particularly significant with respect to F2. The size of the vowel space was significantly smaller in the hearing-impaired children. Finally, a smaller acoustic differentiation between the vowels was observed in children with hearing impairment. The results show that even after 5 years of device use, the acoustic characteristics of the vowels in hearing-assisted children remain significantly different as compared to their NH peers.

Nasalance and nasality in children with cochlear implants and children with hearing aids

OBJECTIVES

In prelingually deaf children, many speech production aspects including resonance, are known to be problematic. This study aimed to investigate nasality and nasalance in two groups of prelingually hearing impaired children, namely deaf children with a cochlear implant (CI) and moderate-to-severely hearing impaired hearing aid (HA) users. The results of both groups are compared with the results of normal hearing children. Besides, the impact of the degree of hearing loss was determined.

METHODOLOGY

36 CI children (mean age: 9;0y), 25 HA children (mean age: 9;1y) and 26 NH children (mean age: 9;3y) were assessed using objective assessment techniques and perceptual evaluations in order to investigate the nasal resonance of the three groups. Ten HA children had thresholds above 70dB (range: 91dB-105dB) and fifteen below 70dB (range: 58dB-68dB). The Nasometer was used for registration of the nasalance values and nasality was perceptually evaluated by two experienced speech therapists using a nominal rating scale (consensus evaluation).

RESULTS

For nasal stimuli, both CI children and HA children showed lower nasalance values in comparison with NH children. The opposite was observed for the oral stimuli. In both hearing impaired groups, cul-de-sac-resonance was observed on a significantly larger scale than in the NH group, and the HA children were judged to be significantly more hypernasal in comparison with NH children.

CONCLUSIONS

Despite the fact that a substantial number of the CI and HA children demonstrate normal (nasal) resonance quality, this aspect of speech production is still at risk for hearing impaired children.