Cochlear implants in young children: the relationship between speech perception and speech intelligibility

Prognostic factors in pediatric cochlear implant: an outcome-based study

OBJECTIVE

To determine the prognostic factors in the pediatric cochlear implant (CI) outcome.

MATERIALS AND METHODS

This prospective cohort study was conducted on 289 pediatric cases with prelingual hearing loss who received cochlear implantation. Several possible salient factors have been recorded. Auditory and speech evaluations were performed before CI, as well as 6 and 12 months after surgery, using Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) tests.

RESULTS

According to univariate analysis, age at the time of surgery was a statistically significant factor. Neurological problems in the child, history of newborn infectious diseases, history of hearing aid use, proper parental cooperation, and round window approach were all significantly related to better auditory or speech outcomes. On the other hand, good parental cooperation and age (for CAP) and good parental cooperation, age, history of infectious disease, and hearing aids use (for SIR) are the significant factors in the multivariate setting.

CONCLUSION

As evidenced by the obtained results, age, background diseases, history of rehabilitation with hearing aids, and surgical details are essential factors to be taken into account in the case-selection process.

Auditory perception in pediatric cochlear implant users with cochlear nerve hypoplasia

OBJECTIVES

The objectives of this study were to assess auditory perception and speech intelligibility outcomes in children with cochlear nerve (CN) hypoplasia who received cochlear implants (CIs) using Categories of Auditory Performance II (CAP II) and Speech Intelligibility Rating (SIR) scales.

METHODS

In total, 40 children who received CI and who were aged between 3 and 18 years were included in this study. The study group included 20 children with CN hypoplasia at least one ear, while the control group included 20 children with normal cochleas and cochlear nerve structures. All children in the study and control groups who participated were evaluated using the CAP II and the SIR scale. Demographic data were collected.

RESULTS

Significant differences were found between the study and control groups' CAP II and SIR scores (p < 0.001). It was found that CAP II scores were positively correlated with SIR scores in the study (r = 0.743, p < 0.001) and control (r = 0.601, p < 0.001) groups. In the study group, significant negative correlations were found between SIR scores and age at implantation (r = -0.674, p = 0.004) and between CAP II scores and age at implantation (r = 0.751, p = 0.003). In the control group, a significant negative correlation was found between age at implantation and CAP II scores (r = -0.805, p = 0.001). Similarly, a significant negative correlation was found between age at implantation and SIR scores (r = -0.702, p = 0.007).

CONCLUSION

Even for children with severe inner ear malformation and CN hypoplasia, CI is an effective treatment modality for auditory perception and speech production. However, it should be noted that CN hypoplasia affects auditory performance negatively in children with CI.

The development of auditory performance and speech perception in CI children after long-period follow up

PURPOSE

The main purpose of the current study was to assess the development of auditory and speech perception and the effects of the age at implantation in CI children after long-period follow up.

MATERIALS AND METHODS

Five hundred and forty-four young children participated in this study (339 males and 205 females). The age at implantation ranged from 6 months to 36 months. All subjects were prelingually bilateral profound sensorineural hearing loss. They were divided into 3 groups according to the implant ages: group 1 (age at implantation < 12 months, n = 109); group 2 (12 months < age at implantation < 24 months, n = 284); and group 3 (24 months < age at implantation < 36 months, n = 151). The categorical auditory performance (CAP) was used to assess auditory abilities and the speech intelligibility rating (SIR) was used to assess the speech intelligibility of these CI children. The tests were administered at pre-surgery and 1, 3, 6, 12, 24, 36, 48- and 60-months post-surgery.

RESULTS

All the subjects demonstrated improvements of auditory abilities and speech intelligibility after CI surgery. The auditory ability developed quickly in 12 months after implantation. However, the speech intelligibility scores show rapid improvement within 24 months post implantation. Significant difference was found between group 1 and group 3, group 2 and group 3 before 12 months post-implantation for CAP and SIR. The three groups of children showed similar development pattern for their auditory abilities and speech intelligibility.

CONCLUSION

The results of this study suggested dramatic and continuous improvement of the auditory and speech abilities post implantation in these CI children. Furthermore, the age at implantation played a considerably smaller role in the improvement of hearing and speech abilities. However, earlier implantation still benefits the language development.

Prosodic control in imitative speech of preschool-age children with cochlear implants

This study aimed to (a) to investigate the acoustic characteristics of speech in preschool-age children with cochlear implants (CIs) compared to those in age-matched children with normal hearing (NH), (b) to identify which acoustic measures could differentiate children with CIs from children with NH, (c) to explore the relationships between child variables and the perceptually judged ability to control prosody in the CI group, and (d) to examine predictors of perceptually judged ability in children with CIs to control prosody. Study participants included 30 children with CIs (3-5.9 years old) and 30 age-matched children with NH. Children were asked to imitate 20 utterances, which were syntactically matched 10 statements and 10 questions. Fundamental frequency, intensity, and duration measures were obtained from the final word of each utterance. Ten adults rated the prosodic-contour appropriateness of the children with CIs using a 5-point scale. Children with CIs tended to produce less distinctive declarative and interrogative utterances compared to children with NH. The mean F0 significantly differentiated children with CIs from their NH peers. In children with CIs, perceptual ratings of prosodic-contour appropriateness were significantly correlated with age, duration of implant use, and percentage of consonants corrects. Duration of implant use was a significant factor predicting the ability to control prosody in children with CIs. These findings suggested that preschool-age children with CIs have difficulty in controlling pitch parameters, compared with the NH peers. The prosodic development in children with CIs was affected by the hearing experience via CIs.

Assessing Fine-Grained Speech Discrimination in Young Children With Bilateral Cochlear Implants

HYPOTHESIS

Children of 2 to 3 years old with cochlear implants can perform consonant discriminations using fine-grained acoustic cues.

BACKGROUND

Children born with severe-to-profound deafness are provided with early cochlear implantation (<2 yr) to maximize oral communication outcomes. Little is known regarding their abilities to discriminate consonant contrasts for accurately identifying speech sounds.

METHODS

Using a Reaching for Sound paradigm to collect behavioral responses, consonant contrast discrimination was measured in 13 children with bilateral cochlear implants (BiCIs; aged 28-37 mo), and 13 age-matched normal-hearing (NH) children. Four contrast pairs were tested: 1) place + voicing, 2) place, 3) voicing, and 4) reduced voice-onset-time cue. Using standard processing strategies, electrodograms showing pulsatile stimulation patterns were created retrospectively to assess the spectral-temporal cues delivered through the clinical speech processors.

RESULTS

As a group, children with BiCIs were able to discriminate all consonant contrasts at a level that was above chance, but their performance was poorer than NH children. Larger individual variability in discrimination performance was found in children with BiCIs. Stepwise regression revealed that, in the place contrast, chronological age was correlated with improved discrimination performance among children with BiCIs.

CONCLUSION

Children with BiCIs were able to discriminate consonant contrasts using fine-grained spectral-temporal cues above chance level but more poorly than their NH peers. Electrodogram analysis confirmed the access to spectral-temporal cues in the consonant contrasts through clinical speech processors. However, the cue saliency might not have be enough for children with BiCIs to achieve the same discrimination accuracy as NH children.

Cultural Identity of Young Deaf Adults with Cochlear Implants in Comparison to Deaf without Cochlear Implants and Hard-of-Hearing Young Adults

This study examined the relationships between cultural identity, severity of hearing loss (HL), and the use of a cochlear implant (CI). One hundred and forty-one adolescents and young adults divided into three groups (deaf with CI, deaf without CI, and hard-of-hearing (HH)) and 134 parents participated. Adolescents and young adults completed questionnaires on cultural identity (hearing, Deaf, marginal, bicultural-hearing, and bicultural-deaf) and communication proficiencies (hearing, spoken language, and sign language). Parents completed a speech quality questionnaire. Deaf participants without CI and those with CI differed in all identities except marginal identity. CI users and HH participants had similar identities except for a stronger bicultural-deaf identity among CI users. Three clusters of participants evolved: participants with a dominant bicultural-deaf identity, participants with a dominant bicultural-hearing identity and participants without a formed cultural identity. Adolescents and young adults who were proficient in one of the modes of communication developed well-established bicultural identities. Adolescents and young adults who were not proficient in one of the modes of communication did not develop a distinguished cultural identity. These results suggest that communication proficiencies are crucial for developing defined identities.

Validation of the second version of the LittlEARS® Early Speech Production Questionnaire (LEESPQ) in German-speaking children with normal hearing

INTRODUCTION

The introduction of neonatal hearing screening and the increasingly early age at which children can receive a cochlear implant has intensified the need for a validated questionnaire to assess the speech production of children aged 0‒18. Such a questionnaire has been created, the LittlEARS^® Early Speech Production Questionnaire (LEESPQ). This study aimed to validate a second, revised edition of the LEESPQ.

METHODS AND MATERIALS

Questionnaires were returned for 362 children with normal hearing. Completed questionnaires were analysed to determine if the LEESPQ is reliable, prognostically accurate, internally consistent, and if gender or multilingualism affects total scores.

RESULTS

Total scores correlated positively with age. The LEESPQ is reliable, accurate, and consistent, and independent of gender or lingual status. A norm curve was created.

DISCUSSION

This second version of the LEESPQ is a valid tool to assess the speech production development of children with normal hearing, aged 0‒18, regardless of their gender. As such, the LEESPQ may be a useful tool to monitor the development of paediatric hearing device users.

CONCLUSION

The second version of the LEESPQ is a valid instrument for assessing early speech production of children aged 0‒18 months.

The experience of bilateral cochlear implantation in a child with LEOPARD syndrome

We present a 3-year old boy with Leopard syndrome. His clinical manifestations included a congenital bilateral sensorineural hearing loss. He underwent cochlear implantation on the right side at age 1 year and on the left side at age 1.5 years. The patient is doing very well and mainstreamed in a regular pre-school program with a teacher of the deaf and home based speech therapy. Bilateral cochlear implantation in the case of a child with Leopard syndrome can be successful.

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.

Proximate factors associated with speech intelligibility in children with cochlear implants: A preliminary study

The purpose of this descriptive pilot study was to examine possible relationships among speech intelligibility and structural characteristics of speech in children who use cochlear implants. The Beginners Intelligibility Test (BIT) was administered to 10 children with cochlear implants, and the intelligibility of the words in the sentences was judged by panels of naïve adult listeners. Additionally, several qualitative and quantitative measures of word omission, segment correctness, duration, and intonation variability were applied to the sentences used to assess intelligibility. Correlational analyses were conducted to determine if BIT scores and the other speech parameters were related. There was a significant correlation between BIT score and percent words omitted, but no other variables correlated significantly with BIT score. The correlation between intelligibility and word omission may be task-specific as well as reflective of memory limitations.

Cochlear implantation for a child with cochlear nerve deficiency: parental perspectives explored through narrative

OBJECTIVE

The objective of this study was to explore, from the parents' perspectives, decision-making regarding a cochlear implant (CI) for their child when a favourable outcome is less likely because of abnormal neurophysiology.

DESIGN

The primary research method of this single case study was qualitative interviewing drawing on a narrative approach to elicit the parents' perspectives about their experiences over time. Each parent was interviewed separately, but thematic analyses were undertaken both within and across interviews in order to identify overlaps and differences.

STUDY SAMPLE

Participants included the parents of a five-year old child with severe-profound hearing loss, cochlear nerve deficiency, and bilateral common cavities who had received a CI at the age of 18 months.

RESULTS

Four themes were identified across the four narrative stages that emerged from the parents' accounts of their experiences regarding their daughter's CI. Themes included hope and despair, questioning professionals' motivations, does deafness need a cure, and bringing the child into the family. Although these themes emerged from both parents' accounts, each parent expressed different perspectives and insights within them.

CONCLUSIONS

Findings highlight the central place of parental needs and perspectives in decision-making regarding a CI, particularly in the context of uncertain outcomes.

Audiological findings in otospondylomegaepiphyseal dysplasia (OSMED) associated with a novel mutation in COL11A2

The aim of the study was to assess the audiological findings of a 4-year-old child with a homozygous COL11A2 mutation and to point out the role of continuous follow-ups in children with craniofacial syndromes after the newborn hearing screening. A 4-year-old boy with otospondylomegaepiphyseal dysplasia (OSMED) was followed up after birth for hearing loss. Transient Otoacoustic Emissions (TEOAEs), Distortion Product Otoacoustic Emissions (DPOAEs), Automated and Clinical Auditory Brainstem Response (AABR and ABR) measurements, Visual Reinforcement Audiometry, immitansmetric measurements and hearing threshold measurements were performed for audiological evaluation. The patient developed sensorineural hearing loss at 11 months of age while his hearing was normal at birth. Because of auditory-verbal training with hearing aids started at 20 months of age, he now has normal verbal communication with his peers. This study clearly demonstrates that hearing loss develops in infancy in patients with OSMED and underscores the importance of continued hearing screening beyond newborn period for early intervention of hearing impairment and communication problems.

Functional outcome of sequential bilateral cochlear implantation in young children: 36 months postoperative results

OBJECTIVE

To examine the effects of sequential bilateral cochlear implantation (CI) on the life of young children after 36 months of bilateral implant use.

METHOD

Thirty-five children were assessed prior to and 3 until 36 months after activation of the second CI. Main outcome measures were: the Categories of Auditory Performance (CAP), Speech Intelligibility Rating (SIR), communication mode, classroom placement, parent reports and the Würzburg questionnaire. Results were analysed separately for children younger and older than 6 years at the time of the second implantation.

RESULTS

At the 3-year test interval, 80% of the younger children attended mainstream schools and were comprehensible for all listeners. They all used oral communication and almost 70% of them could have a conversation over the telephone. After 3 years of bilateral implant use less than 50% of the older children obtained the highest score on the SIR and CAP. Approximately 70% of them was integrated in mainstream schools and used oral communication. All parents reported a more natural communication and an improved quality of life.

CONCLUSIONS

Sequential bilateral implantation seems to offer a wide range of participation benefits to all children and facilitates the social intercourse with their hearing environment.

Receptive language outcomes in children after cochlear implantation

OBJECTIVES

The objectives of the present study were (1) to assess receptive language scores in children after cochlear implantation and compare them with scores in normal hearing children and children with hearing loss that use hearing aids and (2) to determine how demographic factors, such as age of implantation, impact language outcomes.

STUDY DESIGN

Case series.

SUBJECTS/METHODS

Receptive language scores in children with profound prelingual hearing loss who received cochlear implants between 1996 and 2004 were analyzed.

RESULTS

Standardized language assessments were available for 36 children. The average age at implantation was 33 months. The mean language scores for implanted children were within 1 standard deviation of scores of normal hearing individuals. Children with cochlear implants had significantly higher subtest scores (P < 0.05) than children with hearing aids. Children with additional disabilities had significantly (P < 0.05) poorer language performance.

CONCLUSIONS

Pediatric cochlear implant recipients acquire receptive language skills that approach those of their hearing peers and exceed those of children with hearing aids.

Development of speech intelligibility and narrative abilities and their interrelationship three and five years after paediatric cochlear implantation

This study sought to determine the level of speech intelligibility, narrative abilities, and their interrelationship in 18 Finnish children implanted at the average age of three years, four months. Additionally, background factors associated with speech intelligibility and storytelling ability were examined. Speech intelligibility was examined by means of an item identification task with five listeners per child. Three and five years after activation of the implant, the children reached average intelligibility scores of 53% and 81%, respectively. The story generation abilities of the implanted children exceeded their hearing age by one year, on average. This was found after comparing their results with those of normally-hearing two- to six-year-olds (N = 49). According to multiple regression analysis, comorbidity (number of additional needs), chronological age, and/or age at activation usually explained from 46% to 70% of the variation in speech intelligibility and narrative abilities. After controlling for age, communication mode, and number of additional needs, speech intelligibility and ability to narrate were statistically significantly associated with each other three years after activation, but not anymore five years after activation.

Fricatives, affricates, and vowels in Croatian children with cochlear implants

The aim of the research was to analyse the speech of children with cochlear implants over approximately a 46-month period, and compare it with the speech of hearing controls. It focused on three categories of sounds in Croatian: vowels (F1 and F2 of /i/, /e/, /a/, /o/ and /u/), fricatives /s/ and /integral/ (spectral differences expressed in terms of center of gravity), and affricates /ts/ and /t integral/ (accuracy, total duration, and pattern of stop-fricative components). One group of subjects were 10 implanted children who had been profoundly deaf before implantation. There were four recordings per child. Group two children were hearing controls matched for age and sex. The results show that the implanted children are closest to unimpaired children in terms of their formant-defined vowel space. Their fricatives exhibit poor distinction in terms of the noise spectrum, and the affricates are the most difficult to produce.

Acoustic analysis of the speech of children with cochlear implants: a longitudinal study

The aim of the study was to analyse the speech of the children with cochlear implants, and compare it with the speech of hearing controls. We focused on three categories of Croatian sounds: vowels (F1 and F2 frequencies), fricatives (noise frequencies of /s/ and /S/ ), and affricates (total duration and the pattern of stop-fricative components in /ts/ and /tS/ ). Eighteen implanted children, aged between 9;5 and 15;2 years participated in the study. All had been profoundly hearing impaired before implantation. Three recordings per child were made over a 20-month period. The hearing controls were matched for age and sex. Implanted children had a smaller and fronted vowel space, their /s/ and /S/ noise frequencies overlapped, affricates were longer, with a high proportion of incorrect productions and substitutions. With time, there was a small but steady overall improvement in all categories. Early intervention (rehabilitation and implantation) are crucial for good speech acquisition.

Hearing-impaired children in the United Kingdom, I: Auditory performance, communication skills, educational achievements, quality of life, and cochlear implantation

OBJECTIVES

The objectives of this study were to identify variables that are associated with differences in outcome among hearing-impaired children and to control those variables while assessing the impact of cochlear implantation.

STUDY DESIGN

In a cross-sectional study, the parents and teachers of a representative sample of hearing-impaired children were invited to complete questionnaires about children's auditory performance, spoken communication skills, educational achievements, and quality of life. Multiple regression was used to measure the strength of association between these outcomes and variables related to the child (average hearing level, age at onset of hearing impairment, age, gender, number of additional disabilities), the family (parental occupational skill level, ethnicity, and parental hearing status), and cochlear implantation.

RESULTS

Questionnaires were returned by the parents of 2858 children, 468 of whom had received a cochlear implant, and by the teachers of 2241 children, 383 of whom had received an implant. Across all domains, reported outcomes were better for children with fewer disabilities in addition to impaired hearing. Across most domains, reported outcomes were better for children who were older, female, with a more favorable average hearing level, with a higher parental occupational skill level, and with an onset of hearing-impairment after 3 years. When these variables were controlled, cochlear implantation was consistently associated with advantages in auditory performance and spoken communication skills, but less consistently associated with advantages in educational achievements and quality of life. Significant associations were found most commonly for children who were younger than 5 years when implanted, and had used implants for more than 4 years. These children, whose mean (preoperative, unaided) average hearing level was 118 dB, were reported to perform at the same level as nonimplanted children with average hearing levels in the range from 80 dB to 104 dB, depending on the outcome measure.

CONCLUSIONS

When rigorous statistical control is exercised in comparing implanted and nonimplanted children, pediatric cochlear implantation is associated with reported improvements both in spoken communication skills and in some aspects of educational achievements and quality of life, provided that children receive implants before 5 years of age.

Speech perception of children with cochlear implants and children with traditional hearing aids

The aim of the study was to analyse speech perception of children with cochlear implants (N = 29) and children fitted with traditional hearing aids (N = 20). One- and two-syllable words were presented auditorily in a forced choice minimal-pair discrimination task. The children repeated the word and pointed to the appropriate picture presented on computer screen. The words were minimal pairs with respect to voicing or place of articulation in stops and fricatives; among affricates the minimal pairs included the most frequently substituted fricatives and stops in addition to voicing and place of articulation. Vowel discrimination was tested in minimal pairs and in nonsense words differing only in the vowel. Unaided, all children were profoundly hearing impaired and were included in auditory-oral therapy (Verbotonal method). The smallest differences between the groups were found for stops and vowels, and the largest for fricatives and affricates. The implanted children were significantly more successful.

Phonological awareness in deaf children who use cochlear implants

A short-term longitudinal study was conducted to investigate possible benefits of cochlear implant (CI) use on the development of phonological awareness in deaf children. Nineteen CI users were tested on 2 occasions. Two groups of deaf children using hearing aids were tested once: 11 profoundly deaf and 10 severely deaf children. A battery of tests was designed to investigate syllable, rhyme, and phoneme awareness. Syllable awareness in the CI users was equivalent to that of the severely deaf group, and rhyme and phoneme awareness was similar to that of the profoundly deaf children using hearing aids. CI use affords some benefit to the development of phonological awareness. The results from this study indicate that this enhancement is first observable at the syllable level.

Long-Term Functional Outcomes and Academic-Occupational Status in Implanted Children After 10 to 14 Years of Cochlear Implant Use

OBJECTIVES

To assess a group of consecutively implanted children over 10 years after implantation with regard to implant device use and function, speech perception, and speech intelligibility outcomes; and to document current academic or occupational status.

STUDY DESIGN

A prospective longitudinal study assessing device function, device use, speech perception, speech intelligibility, and academic/occupational status of implanted deaf children.

SETTING

Pediatric tertiary referral center for cochlear implantation.

METHODS

The auditory performance and speech intelligibility development of 30 profoundly deaf children were rated before cochlear implantation and at 5 and 10 years after implantation using the Categories of Auditory Performance and the Speech Intelligibility Rating. The academic and/or occupational status of the participants after 10 years of implant experience was documented. All children received a Nucleus multichannel cochlear implant between the ages of 2.5 and 11 years (mean age at implantation, 5.2 yr). Implant experience ranged from 10 to 14 years of use.

RESULTS

After 10 years of implant experience, 26 subjects (87%) reported that they always wore their device; 2 subjects (7%), frequently; and 1 subject (3%), occasionally. Only one child had discontinued use of his device. After 10 years of implant use, 26 (87%) of the children understood a conversation without lip reading and 18 (60%) used the telephone with a familiar speaker. Ten years after implantation, 23 (77%) of the subjects used speech intelligible to an average listener or a listener with little experience of a deaf person's speech. One-third to one-half of the implanted children continued to demonstrate improvements at 5 to 10 years of implant use. Of the 30 implanted children, 8 (26.7%) experienced nine device failures. The length of time from identification of the first faulty electrode to reimplant surgery ranged from 2 weeks to 5.5 years, as several failures were gradual or intermittent. However, all children were successfully reimplanted. At the end of the study (10-14 yr after implantation), 19 subjects were in secondary school for children aged 11 to 16 years: 6 were in mainstream schools, 7 were in specialist hearing-impaired units attached to a mainstream secondary school, and 6 were in schools for the deaf. Of the remaining 11 subjects, 4 were in college studying vocational subjects, 2 were in a university studying for a bachelor's degree, 3 were working full-time, 1 was working and going to a university part-time, and 1 was a full-time mother of two young children.

CONCLUSION

All but 1 of the 30 implanted children continue using their devices 10 to 14 years after implantation, showing significant progress in speech perception and production. Device failure was frequent, but successful reimplantation occurred in all cases. One-third to one-half of the implanted children in this study continued to demonstrate improvements at 5 to 10 years of implant use. All children are studying or working and are actively involved in their local communities. The results suggest that cochlear implantation provides long-term communication benefit to profoundly deaf children that does not plateau for some subjects even after reimplantation. This study further indicates that cochlear implant centers need the structure and funding to provide long-term support, counseling, audiologic follow-up, rehabilitation, and device monitoring to implanted children.

Prelexical Vocalization in Normal Hearing and Hearing-Impaired Infants Before and After Cochlear Implantation and Its Relation to Early Auditory Skills

OBJECTIVES

To compare the vocalizations of hearing-impaired infants before and after cochlear implantation with those of a control group of hearing infants and to relate prelexical vocalizations by using the PRoduction Infant Scale Evaluation (PRISE) to early auditory skill attainments, using the Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS) in normal-hearing and hearing-impaired (HI) infants before and after cochlear implantation.

DESIGN

A total of 187 infants participated in the study: 24 HI infants with severe-profound hearing loss (8 to 23 months of age) and 163 hearing infants (0.5 to 20 months of age). Prelexical vocalizations and early auditory skills were assessed by using parent questionnaires (PRISE and IT-MAIS, respectively) that reflect known milestones in the infant's vocal and auditory development. HI infant data were compared with hearing infant data according to chronological age and duration of device use (hearing aid or cochlear implant).

RESULTS

Average PRISE score of aided HI infants before implantation was 50% or less (regardless of age). This score is comparable to that of hearing infants who are 6 to 7 months of age. After implantation, HI infants reached a score of 70% but did not reach normative performance. When HI infant data were compared with hearing infants by duration of device use, aided infants before implantation performed as well or worse than normative performance, whereas implanted infants performed as well as or better than hearing infants. Performance on individual PRISE questions showed limited ability by HI infants before implantation compared with hearing and implanted infants. A strong correlation was found between the IT-MAIS and the PRISE (r = 0.93 and r = 0.83, for hearing and HI infants, respectively).

CONCLUSIONS

The PRISE was found to be a versatile tool for implant team clinicians who are required to assess prelinguistic skills of infants. The findings suggest that early auditory skills are related to prelexical vocalization. The data also highlighted unanswered questions related to the importance of early fitting of hearing aids on vocalization before and after implantation.

Speech intelligibility of Mandarin-speaking deaf children with cochlear implants

OBJECTIVE

Speech intelligibility, the extent to which the speakers can be understood verbally by their listeners, is an evaluator for the effectiveness of cochlear implantation. Thus, our goals were to evaluate the result of a tonal language through comparing the speech intelligibility between normal-hearing and implanted children who speak Mandarin, and to evaluate the relationship between speech intelligibility and duration of implants use. The effects of the age at implantation were also evaluated.

METHODS

Twenty-six children (mean age of 5.9 years), who were congenitally deaf and implanted age at 3.5 years, were compared with 26 normal-hearing children (mean age of 5.84 years). The average post-implanted time was more than 6 months. Speech intelligibility was represented with the speech intelligibility ratings (SIR) and the correct percentage of dictation. The relationships between speech intelligibility, age at implantation and duration of implant were evaluated by linear regression analysis.

RESULTS

Speech intelligibility of most subjects ranked from SIR category 3-5. The average correct perception rate (CI group/normal group) of words, consonants, vowels, and tones were 42.5%, 64.9%, 73.5%, and 72.3%, respectively. These differences were statistically significant (p<0.001). Speech intelligibility was positively correlated with age only in the normal-hearing group. Speech intelligibility in the implanted group was negatively correlated with age at implantation but positively correlated with the duration of implant.

CONCLUSIONS

Speech intelligibility of tonal language was poorer in implanted children than normal-hearing children, but their communication outcomes were satisfactory when measured with SIR. Speech intelligibility is better if the age at implantation is younger or duration of implants use is longer.

Perception and production of mandarin tones in prelingually deaf children with cochlear implants

OBJECTIVE

Mandarin is a lexical tone language in which four tones are crucial for determining lexical meanings. Acquisition of such a tone system may be challenging to prelingually deaf children with cochlear implants because, as recent studies have shown, cochlear implant devices are ineffective in encoding voice pitch information required for tone recognition. This study aimed to investigate Mandarin tone production and perception skills of children with cochlear implants.

DESIGN

Thirty prelingually deaf children with cochlear implants, ages 6;0 (yr;mo) to 12;6, participated. These children received their implants at an average age of 5;8, with a range from 2;3 to 10;3. The average length of their cochlear implant experience was 3;7, with a range from 1;7 to 6;5. Tasks of tone production and tone identification involved a pictorial protocol of 48 words containing the targeted tones in either monosyllabic or disyllabic forms.

RESULTS

The average scores for tone production was 53.09% (SD = 15.42), and for tone identification was 72.88% (SD = 19.68; chance level = 50%). Significant differences were found in the percentages across the production or identification of tone types or tone pairs. The children with exceptional performance in tone production tended to also perform well in tone identification. The children's performance levels in tone identification and production were also discussed in relation to the factors of age at implantation and length of cochlear implant experience.

CONCLUSIONS

The present results suggest that the majority of prelingually deaf children with cochlear implants did not master Mandarin tone production. However, a small group of participants demonstrated nearly perfect skills of Mandarin tone production in addition to tone perception. Thus, it is necessary to consider factors other than the device's limitations to explain these high levels of performance in the perception and production of Mandarin lexical tones.

Connexin 26 (GJB2) Gene-Related Deafness and Speech Intelligibility After Cochlear Implantation

HYPOTHESIS

Speech intelligibility in children after cochlear implantation may depend on their deafness cause, including connexin 26 (GJB2) gene-related deafness.

BACKGROUND

There is significant variability in the degree of intelligibility, or clarity, of children's speech after cochlear implantation. GJB2 gene-related deafness may be a factor, as preliminary data suggest that pathologic changes do not affect the spiral ganglion cells, which are the neural elements stimulated by the implant, thus favoring better results.

METHODS

In an observational retrospective cohort study of pediatric cochlear implantees, 38 patients with nonsyndromic deafness of unknown cause and 1 with keratitisichthyosis-deafness syndrome underwent GJB2 mutation analysis using polymerase chain reaction amplification and direct sequencing. The primary outcome measure assessed was Speech Intelligibility Rating score from postoperative Year 1 (n = 39) to Year 5 (n = 17). Educational setting was considered as a secondary outcome measure. Statistical analysis was double-blinded, with patients and assessors of outcome unaware of GJB2 status.

RESULTS

Fourteen patients had GJB2-related deafness and 25 had GJB2-unrelated deafness. Comparisons at Year 3 (n = 31) revealed intelligible speech achieved by 9 of 11 with GJB2-related deafness, compared with only 6 of 20 with GJB2-unrelated deafness (p = 0.017). Ordinal logistic regression analysis on Speech Intelligibility Rating scores found statistically significantly better scores in children with GJB2-related deafness (p < 0.05) both before and after adjustment for confounding variables. A larger proportion with GJB2-related deafness also attended mainstream school (p = 0.01).

CONCLUSION

In pediatric cochlear implantees, GJB2-related deafness is a predictor of good speech intelligibility.

Nonword repetition by children with cochlear implants: accuracy ratings from normal-hearing listeners

Seventy-six children with cochlear implants completed a nonword repetition task. The children were presented with 20 nonword auditory patterns over a loud-speaker and were asked to repeat them aloud to the experimenter. The children's responses were recorded on digital audiotape and then played back to normal-hearing adult listeners to obtain accuracy ratings on a 7-point scale. The children's nonword repetition performance, as measured by these perceptual accuracy ratings, could be predicted in large part by their performance on independently collected measures of speech perception, verbal rehearsal speed, and speech production. The strongest contributing variable was speaking rate, which is widely argued to reflect verbal rehearsal speed in phonological working memory. Children who had become deaf at older ages received higher perceptual ratings. Children whose early linguistic experience and educational environments emphasized oral communication methods received higher perceptual ratings than children enrolled in total communication programs. The present findings suggest that individual differences in performance on nonword repetition are strongly related to variability observed in the component processes involved in language imitation tasks, including measures of speech perception, speech production, and especially verbal rehearsal speed in phonological working memory. In addition, onset of deafness at a later age and an educational environment emphasizing oral communication may be beneficial to the children's ability to develop the robust phonological processing skills necessary to accurately repeat novel, nonword sound patterns.

The auditory performance in children using cochlear implants: effects of mental function

OBJECTIVE

Mental function is considered to affect the post-operative outcomes of deaf children with cochlear implants. The purpose of this study is to evaluate the effect of mental function on the auditory performance in children with cochlear implants.

METHODS

In a retrospective review of data, 26 pre-lingual deafened children received pre-operative evaluation of mental function and were divided into normal and retarded groups. Categories of auditory performance scale (CAP) was conducted at 1-year intervals after implantation. ANCOVA was used for statistic analysis.

RESULTS

The average scores of auditory performance in normal group (n=14) were 3.93 (S.D. 1.07) and 5.86 (S.D. 0.95) at 1- and 2-year post-implantation. While the average scores in the retarded group were 2.5 (S.D. 1.51) and 4.17 (S.D. 1.85), both groups demonstrated obvious improvement in speech perception (F 103.12, P<0.001) during the first 2 post-operative years. The auditory performance in the normal group was significantly superior to the retarded group (F 8.67, P<0.01). However, the interaction between the duration of the device use and mental status showed no significant difference in the auditory perception performance (F 1.575, P=0.222).

CONCLUSIONS

The results revealed the mental function plays as one of the predictive parameters of auditory performance in profoundly hearing impaired children after cochlear implantation.

Assessing candidate children for cochlear implantation with the Nottingham Children's Implant Profile (NChIP): the first 200 children

BACKGROUND/OBJECTIVE

Nottingham Children's Implant Profile (NChIP) is a profile designed to assess candidate children for cochlear implantation. It includes the demographic details of the children (chronological age and duration of deafness), medical and radiological conditions, the outcomes of audiological assessments, language and speech abilities, multiple handicaps or disabilities, family structure and support, educational environment, the availability of support services, expectations of the family and deaf child, cognitive abilities, and learning style. The aim of the present study is to present the NChIP data obtained on the first 200 children implanted in the same cochlear implant programme and evaluate NChIP's use in the selection phase of cochlear implantation.

PATIENTS

The study assessed 200 profoundly deaf children. Fifty-six children (28%) were deafened by meningitis, 132 (66%) were born deaf, and 12 (6%) were deafened from other causes (head injury, viral infection, progressive deafness).

RESULTS

Chronological age at the time of assessment (before implantation) was the most common factor of major concern (9% of the children studied) and the pre-implant language and speech abilities of the children was the most common factor of mild to moderate concern, affecting 63% of the children. The second most common factor of mild to moderate concern was duration of deafness (37%) and the third was the learning style of the children (33%). Availability of support services was the least factor of concern as 179 children (90%) did not have any problems in this area.

CONCLUSIONS

Earlier identification of deafness (by universal neonatal hearing screening programs) may reduce age at implantation and duration of deafness as areas of concern in the future. However, the pre-implant language and speech abilities of the candidate children, the gap between chronological and language age, and the learning style of children are now emerging as key areas of research in the field. NChIP was found to be a very useful casework tool in the initial evaluation of the deaf children promoting and enhancing interdisciplinary teamwork across the different professionals. NChIP was also used as part of the decision-making process by the cochlear implant programme professionals and as a counselling tool for the parents. Finally, NChIP has helped to identify those children and families who need additional support. In the case of recently established paediatric cochlear implant programmes it would be a 'neutral' yet sensitive way of promoting good interdisciplinary collaboration and also peer support within team discussions when selecting children for cochlear implantation.

Connected speech intelligibility of children with cochlear implants and children with normal hearing

The objective of this study was to compare the connected speech intelligibility of children who use cochlear implants with that of children who have normal hearing. Previous research has shown that speech intelligibility improves from before cochlear implantation to after implantation and that the speech intelligibility of children who use cochlear implants compares favorably with that of children who use conventional hearing aids. However, no research has yet addressed the question of how the speech intelligibility of children who use cochlear implants compares to that of children with normal hearing. In the current study, archival data on connected speech intelligibility from 51 children with cochlear implants were compared with newly collected data from 47 children with normal hearing. Results showed that for children with cochlear implants, greater intelligibility was associated with both increased chronological age and increased duration of cochlear implant use. Consistent with previous studies, children with normal hearing achieved adult-like or near-adult-like intelligibility around the age of 4 years, but a similar peak in intelligibility was not observed for the children who used cochlear implants. On the whole, children with cochlear implants were significantly less intelligible than children with normal hearing, when controlling both for chronological age and for length of auditory experience. These results have implications for the socialization and education of children with cochlear implants, particularly with respect to on-time placement in mainstream educational environments with age peers.

Monosyllable speech perception of Japanese hearing aid users with prelingual hearing loss: implications for surgical indication of cochlear implant

OBJECTIVE

The monosyllable speech perception ability after years of educational intervention was compared between prelingually deafened pediatric hearing aid users and their cochlear implant counterparts.

DESIGN

An open-set monosyllabic speech perception test was conducted on all subjects. The test required subjects to indicate a corresponding Japanese character to that spoken by the examiner. Fifty-two subjects with prelingual hearing impairment (47 hearing aid users and 5 cochlear implant users) were examined.

RESULTS

Hearing aid users with average pure-tone thresholds less than 90 dB HL demonstrated generally better monosyllable perception than 70%, which was equivalent or better performance than that of the cochlear implant group. Widely dispersed speech perception was observed within the 90-99 dB HL hearing-aid user group with most subjects demonstrating less than 50% speech perception. In the cluster of >100 dB HL, few cases demonstrated more than 50% in speech perception. The perception ability of the vowel part of each mora within the cochlear implant group was 100% and corresponding to that of hearing aid users with moderate and severe hearing loss.

CONCLUSION

Hearing ability among cochlear implant users can be comparable with that of hearing aid users with average unaided pure-tone thresholds of 90 dB HL, after monosyllabic speech perception testing was performed.

Exploring the language and literacy outcomes of pediatric cochlear implant users

OBJECTIVE

The principal goal of this study was to investigate the relationship between language and literacy (i.e., reading and writing) skills in pediatric cochlear implant users. A peripheral objective was to identify the children's skills that were in need of remediation and subsequently to provide suggestions for remedial programming. It was predicted that the robust language skills often associated with children who have cochlear implant experience would facilitate the development of literacy skills. It was further proposed that the language and literacy skills of pediatric cochlear implant users would approximate the language and literacy skills of children with normal hearing.

DESIGN

Sixteen pediatric cochlear implant users' language and literacy skills were evaluated and then compared with a reference group of 16 age-matched, normal-hearing children. All 32 participants were educated in mainstream classes within the public school system in the Midwest. The "Sentence Formulation" and "Concepts and Directions" subtests of the Clinical Evaluation of Language Fundamentals-3 test were used to evaluate receptive and expressive language skills. Reading comprehension was evaluated with the "Paragraph Comprehension" subtest of the Woodcock Reading Mastery Test. Performance measures for the writing analyses included productivity, complexity and grammaticality measures.

RESULTS

Children with cochlear implants performed within 1 SD of the normal-hearing, age-matched children on measures of language comprehension, reading comprehension and writing accuracy. However, the children with cochlear implants performed significantly poorer than the children with normal hearing on the expressive "Sentence Formulation" subtest. The cochlear implant users also produced fewer words on the written narrative task than did the normal-hearing children, although there was not a significant difference between groups with respect to total words per clause. Furthermore there was a strong correlation between language performance and reading performance, as well as language performance and total words produced on the written performance measure for the children using cochlear implants.

CONCLUSIONS

The results of this study suggest that the language skills of pediatric cochlear implant users are related to and correlated with the development of literacy skills within these children. Consequently, the performance of the cochlear implant users, on various language and literacy measures, compared favorably to an age-matched group of children with normal hearing. There were significant differences in the ability of the cochlear implant users to correctly utilize grammatical structures such as conjunctions and correct verb forms when they were required to formulate written and oral sentences. Given this information, it would be appropriate for their educational or remedial language programs to emphasize the use and development of these structures.

Using SNAP Dragons to monitor narrative abilities in young deaf children following cochlear implantation

OBJECTIVE

To assess the narrative abilities of young deaf children before cochlear implantation and 1 and 2 years following implantation, and to explore possible changes in the implanted children's preferred mode of communication in the narrative abilities task.

STUDY DESIGN

Prospective longitudinal study assessing the narrative abilities of young deaf children before and after cochlear implantation.

SETTING

Pediatric tertiary referral center for cochlear implantation.

PATIENTS AND METHODS

The narrative abilities of 35 young profoundly deaf children were assessed before implantation and 1 and 2 years following implantation using the Stories/Narratives Assessment Procedure. Children with age at implantation less than 6 years were included in the study (mean age at implantation was 3.5 years; range 1.4-5.9 years). All children were filled with the Nucleus multichannel cochlear implant system. With respect to their communication modes, they came from a wide range of backgrounds and all children were encouraged to use their preferred mode of communication during the narrative task.

RESULTS

The data showed that there was a statistically significant increase in narrative abilities across the three data points (P<0.001). Before receiving the implant, children were mostly in the pre-structural, receptive stages and could at most label or comment on the pictures (median narrative stage 2). By the 2-year interval, children were mostly using one or two categories or one complete episode with spontaneous retelling (median narrative stage 4). Although children were not pressured to use any particular communication mode, a shift to speech was found following implantation and this was statistically significant (P<0.001).

CONCLUSION

Young implanted deaf children showed a significant progress in their narrative abilities through time and a significant shift in the predominant mode of communication towards more speech orientated communication modes following cochlear implantation.

Factors associated with development of speech production skills in children implanted by age five

OBJECTIVE

This study investigated speech production outcomes and the factors influencing the outcomes in children who had 4 to 6 yr of experience with a multichannel cochlear implant. Production variables examined included speech intelligibility, accuracy of consonant and vowel production, percentage of plosives and fricatives produced, duration of sentences, percentage of time involved in communication breakdowns during a communication sample, and responses to a speech usage questionnaire.

DESIGN

181 children between the ages of 8 and 9 yr who received a multichannel cochlear implant before age 5 yr participated as subjects. Independent variables were the amount and type of educational intervention and intervening variables were distributed across child, family and implant characteristics. Multiple regression analyses provided a measure of the amount of variance associated with speech production skills accounted for by the intervening and independent variables.

RESULTS

Performance for the key words in the speech intelligibility measured averaged 63.5% for the group of children. Accuracy of phoneme production was higher for consonants (68.0%) than for vowels (61.6%) for the group. More plosives were present for acoustic analyses (91.6%) than were fricatives (78.4%). Duration for the speech intelligibility sentences averaged 2572.3 msec. Communication breakdowns occurred on average 14.5% of the time involved in a language sample. Significant predictors of high levels of oral communication skills included higher nonverbal intelligence, gender, longer use of SPEAK processing strategy, a fully active electrode array, greater dynamic range, and greater growth of loudness. The primary rehabilitative factors contributing to high levels of oral communication were an emphasis on oral-aural communication and classrooms that emphasized dependence on speech and listening.

CONCLUSIONS

Speech production performance in children with cochlear implants is influenced by nonverbal intelligence, gender, implant characteristics including the length of time using the newest speech processing strategies, and educational programs emphasizing oral-aural communication. Factors previously thought to be major contributors to speech production performance, such as age of onset of deafness and age of implantation, did not appear to play significant roles in predicting levels of speech production performance.

Parent interaction course in order to enhance communication skills between parents and children following pediatric cochlear implantation

OBJECTIVE

To assess the effect of a parent interaction training course on the communication skills of parents of young implanted children. The training course was designed to help parents to be less controlling in their interactions with their deaf children and to facilitate the development of spoken language.

STUDY DESIGN

Prospective study comparing the communication skills of parents of deaf children fitted with cochlear implants before and after a parent interaction training course.

SETTING

Pediatric tertiary referral center for cochlear implantation.

METHODS

Video samples were taken of parents interacting with their children 1 month before the course (ranging from 15 days to 2 months) and after the course (ranging from 15 days to 1 month). Video samples were then transcribed orthographically and parents' turns in the interaction were assigned to one of two categories: (a) initiations--the parent initiates conversation or introduces a new topic and (b) responses--the parent responds to the child's previous turn. 12 months after completion of the course, the process was repeated in order to establish the relative permanence of changes in behavior.

HYPOTHESIS

The parents' turns would shift from a predominance of initiations to a predominance of responses as a result of attendance on the course. This would demonstrate that the parents were less controlling of their children in communication and were exhibiting more contingent behavior--responding to their child's initiations rather than expecting the child to respond to theirs.

PATIENTS

The study involved 17 parents of 11 implanted children. The mean age at implantation was 4 years (range: 2.2-6.3 years). The implant experience of the children ranged from 2 to 23 months at the time of the study. All children used total communication.

RESULTS

The post-course initiations were half those of the pre-course ones (median from 14 decreased to 7) and the responses were almost double following the course (median from 8 increased to 14). Both differences were statistically significant (P < 0.05). 12 months after the course, the responses score remained high with a median score of 16.5. However, a slight but significant increase in the initiation scores was also noted (median from 7 to 8.5). Parental satisfaction of the course was found to be high as no families failed to attend on any of the occasions despite the great distances some of them had to travel.

CONCLUSION

The format of the parent interaction training course was found to be highly acceptable to the parents and the components covered proved to be effective in promoting positive changes in parental communication behavior. Clinicians need to provide a responsive environment for implanted deaf children and help others to do the same. The training course provided a very useful forum to share insights and skills and to evaluate ways of enhancing the communication between parents and children following cochlear implantation.

Receptive and expressive language skills of 106 children with a minimum of 2 years' experience in hearing with a cochlear implant

OBJECTIVE

The aim of the study was to assess the speech development of children with at least 2 years' hearing experience with a cochlear implant (CI).

METHODS

One hundred and six children were tested, all of whom had used the CI for at least 2 years. Receptive and expressive language development were tested using the scales of early communication skills for hearing-impaired children after Geers and Moog and the Reynell developmental language scales III. In addition, free-field audiometry was performed. Pre-postoperative measurements were compared statistically, and a linear regression analysis was carried out.

RESULTS

Clear improvements in the gain in functional hearing 2 years after receiving the CI as well as clear improvements in both speech perception and speech production were ascertained. All deviations were statistically highly significant (P<0.000). The receptive and expressive speech test results correlate positively to a great extent. The results of logistic regressive analysis indicate that the speech production measured depends decisively on age at implantation, age at time of test, speech production before implantation, and additional handicaps.

CONCLUSION

Based on the conception of the WHO, a statistically significant improvement of both impairment and disability can be confirmed. In the present study, the regression analysis established the age at implantation as the most important prognostic factor. While the percentage of children with good speech development is larger with early implanted children than with late implanted children, some of the children among the early implanted group show unsatisfactory speech development of unknown origin. Improvements in speech development are likely to be achieved when more children are diagnosed and implanted early. This finding urgently requires the introduction of a general newborn screening program. Thorough anamnesis and assessment during parent counseling of the manifold factors described are a prerequisite for the precise estimation of the difficulties to be met and the expected effectiveness of the implant in each individual case.

Development of speech perception and production in children with cochlear implants

The purpose of the present study was twofold: 1) to compare the hierarchy of perceived and produced significant speech pattern contrasts in children with cochlear implants, and 2) to compare this hierarchy to developmental data of children with normal hearing. The subjects included 35 prelingual hearing-impaired children with multichannel cochlear implants. The test materials were the Hebrew Speech Pattern Contrast (HeSPAC) test and the Hebrew Picture Speech Pattern Contrast (HePiSPAC) test for older and younger children, respectively. The results show that 1) auditory speech perception performance of children with cochlear implants reaches an asymptote at 76% (after correction for guessing) between 4 and 6 years of implant use; 2) all implant users perceived vowel place extremely well immediately after implantation; 3) most implanted children perceived initial voicing at chance level until 2 to 3 years after implantation, after which scores improved by 60% to 70% with implant use; 4) the hierarchy of phonetic-feature production paralleled that of perception: vowels first, voicing last, and manner and place of articulation in between; and 5) the hierarchy in speech pattern contrast perception and production was similar between the implanted and the normal-hearing children, with the exception of the vowels (possibly because of the interaction between the specific information provided by the implant device and the acoustics of the Hebrew language). The data reported here contribute to our current knowledge about the development of phonological contrasts in children who were deprived of sound in the first few years of their lives and then developed phonetic representations via cochlear implants. The data also provide additional insight into the interrelated skills of speech perception and production.