Functional performance among children with cochlear implants and additional disabilities

Abstract

Objective

To assess daily functional skills among young cochlear implant (CI) recipients with additional disabilities.

Methods

Children with CI and developmental disabilities and a hearing control group containing similar ages and similar disabilities were enrolled in a cross-sectional study of language and functional skills. Daily functional skills were measured using the Pediatric Evaluation of Disability Inventory (PEDI), which provides standard and scaled scores in Self-Care, Mobility, and Social Functioning domains. Language was assessed using the Preschool Language Scales, 4th edition which provides standard scores and age equivalents.

Results

Fourteen children with CIs and seven hearing controls were included in this analysis. Most children in this study (90.5%) had cognitive disabilities and 57% had motor disabilities. Compared with the hearing controls, children with CIs were less likely to have functional independence in any PEDI domain. Children with CI had significantly lower median social functioning standard scores compared with controls (17.3 vs. 27.5, P = 0.009). After controlling for nonverbal cognitive abilities and language level, the difference was no longer significant (19.1 vs. 24, P = 0.3). Among children with CI, age at implant and duration with device were not associated (P > 0.4) with PEDI scores.

Discussion

Although children with CI and developmental disabilities had similar functional skills as hearing children with similar disabilities regarding the PEDI domains of Self-Care and Mobility, they had lower Social Function standard scores. This lower social functioning among children with implants may be related to lower language levels and possible language deficits seen in the CI group. Regular assessments of functional abilities coupled with language abilities are essential in providing every child with the opportunity for maximizing the potential for independence.     

Oral communicating children using a cochlear implant: Good reading outcomes are linked to better language and phonological processing abilities

Introduction/objective

Cochlear implantation provides children with a significant hearing loss the potential to engage in phonological processing via audition; however these children can still have poor or inadequately detailed mental (phonological) representations of speech and as such phonological awareness and reading difficulties. Heterogeneous participant profiles, particularly varying modes of communication have clouded the research regarding reading outcomes of children using a cochlear implant. The objective of this study was to explore the relationships between word reading and reading comprehension outcomes, and a range of variables of a relatively homogenous group of children using cochlear implants.

Method

Forty-seven oral communicating children using a cochlear implant and who had attended auditory-verbal therapy served as participants. They were administered a comprehensive battery of 10 different assessments covering 22 different tasks across the domains of speech perception, speech production, language, phonological processing and reading. Correlation and principal component analyses were used to examine the relationships between outcome areas.

Results

Audiologic and demographic variables were not significantly related to reading outcomes, with the exception of family size. Language and word reading were most strongly related to reading comprehension, while phonological awareness and language were most strongly related to word reading. It is proposed that the development of well-specified phonological representations might underlie these relationships.

Conclusion

For oral communicating children using a cochlear implant, good reading outcomes are linked to better language and phonological processing abilities.     

Tone and sentence perception in young Mandarin-speaking children with cochlear implants

ObjectivesThe purpose of this study was to examine the outcomes of cochlear implantation in young children in terms of (1) perception of lexical tones in quiet, (2) perception of sentences in quiet and in noise, (3) the effects of five demographic variables (i.e., preoperative hearing level, age at implantation, duration of cochlear implants use, maternal educational level, and whether a child underwent a hearing aid trial before implantation) on lexical tone perception and sentence perception, and (4) the relationship between lexical tone perception and sentence perception.Methods96 participants, aged from 2.41 years to 7.09 years, were recruited in mainland China. The children exhibited normal cognitive abilities and received unilateral implants at an average age of 2.72 years, with ages ranging from 0.69 to 5 years of age.ResultsThe mean score for tone identification was 77% (SD = 13%; chance level = 50%). Tone 2/tone 3 was the most difficult tone contrast to identify. Children with a longer duration of CI use and whose mothers had more years of education tended to perform better in sentence perception in quiet and in noise. Having undergone a hearing aid trial before implantation and more residual hearing were additional factors contributing to better sentence perception in noise. The only demographical variable that related to tone perception in quiet was duration of CI. In addition, while there was a modest correlation between tone perception and sentence perception in quiet (r_s = 0.47, p < 0.001), the correlation between tone perception in quiet and sentence perception in noise was much weaker (r_s = −0.28, p < 0.05).ConclusionsThe findings suggested that most young children who had been implanted before 5 years of age and had 1–3 years of implant use did not catch up with their aged peers with normal hearing in tone perception and sentence perception. The weak to moderate correlation between tone perception in quiet and sentence perception might imply that the improvement of tone perception in quiet may not necessarily contribute to sentence perception, especially in noise condition.     

Phonological awareness and early reading skills in children with cochlear implants

Abstract

This paper summarizes findings from a population study on outcomes of children with hearing loss in Australia, the Longitudinal Outcomes of Children with Hearing Impairment (http://www.outcomes.nal.gov.au) study. Children were evaluated at several intervals using standardized tests, and the relationship between a range of predictors and the outcomes was examined. This paper reports the performance of children with cochlear implants at 5 years of age together with factors predicting word reading ability. Earlier age at cochlear implantation was significantly associated with better word reading ability, after controlling for the effects of language, receptive vocabulary, nonverbal cognitive ability, and device configuration.     

Auditory, speech and language development in young children with cochlear implants compared with children with normal hearing

Objective

This study had two aims: (1) to document the auditory and lexical development of children who are deaf and received the first cochlear implant (CI) by the age of 16 months and the second CI by the age of 31 months and (2) to compare these children's results with those of children with normal hearing (NH).

Methods

This longitudinal study included five children with NH and five with sensorineural deafness. All children of the second group were observed for 36 months after the first fitting of the device (cochlear implant). The auditory development of the CI group was documented every 3 months up to the age of two years in hearing age and chronological age and for the NH group in chronological age. The language development of each NH child was assessed at 12, 18, 24 and 36 months of chronological age. Children with CIs were examined at the same age intervals at chronological and hearing age.

Results

In both groups, children showed individual patterns of auditory and language development. The children with CIs developed differently in the amount of receptive and expressive vocabulary compared with the NH control group. Three children in the CI group needed almost 6 months to make gains in speech development that were consistent with what would be expected for their chronological age. Overall, the receptive and expressive development in all children of the implanted group increased with their hearing age.

Conclusion

These results indicate that early identification and early implantation is advisable to give children with sensorineural hearing loss a realistic chance to develop satisfactory expressive and receptive vocabulary and also to develop stable phonological, morphological and syntactical skills for school life. On the basis of these longitudinal data, we will be able to develop new diagnostic tools that enable clinicians to assess child's progress in hearing and speech development.     

Prelingual auditory-perceptual skills as indicators of initial oral language development in deaf children with cochlear implants

ObjectivesTo assess when prelingually deaf children with a cochlear implant (CI) achieve the First Milestone of Oral Language, to study the progression of their prelingual auditory skills in the first year after CI and to investigate a possible correlation between such skills and the timing of initial oral language development.MethodsThe sample included 44 prelingually deaf children (23 M and 21 F) from the same tertiary care institution, who received unilateral or bilateral cochlear implants. Achievement of the First Milestone of Oral Language (FMOL) was defined as speech comprehension of at least 50 words and speech production of a minimum of 10 words, as established by administration of a validated Italian test for the assessment of initial language competence in infants. Prelingual auditory-perceptual skills were assessed over time by means of a test battery consisting of: the Infant Toddler Meaningful Integration Scale (IT-MAIS); the Infant Listening Progress Profile (ILiP) and the Categories of Auditory Performance (CAP).ResultsOn average, the 44 children received their CI at 24 ± 9 months and experienced FMOL after 8 ± 4 months of continuous CI use. The IT-MAIS, ILiP and CAP scores increased significantly over time, the greatest improvement occurring between baseline and six months of CI use. On multivariate regression analysis, age at diagnosis and age at CI did not appear to bear correlation with FMOL timing; instead, the only variables contributing to its variance were IT-MAIS and ILiP scores after six months of CI use, accounting for 43% and 55%, respectively.ConclusionPrelingual auditory skills of implanted children assessed via a test battery six months after CI treatment, can act as indicators of the timing of initial oral language development. Accordingly, the period from CI switch-on to six months can be considered as a window of opportunity for appropriate intervention in children failing to show the expected progression of their auditory skills and who would have higher risk of delayed oral language development.     

学前听障儿童人工耳蜗术后语言康复教学研究

目的通过总结18名学前听障儿童植入人工耳蜗后1年内语言康复情况,分析儿童人工耳蜗术后语言康复的特点．为合理制订语言康复教学目标寻找依据,提出建议。方法定期对人工耳蜗术后儿童语言能力进行评估,记录儿童达到各个阶段语言目标的时间。1年后对以上材料进行整理、对比。分析儿童术后语言发展情况。结果18名儿童人工耳蜗术后康复1年的语言能力较术前有明显提高（P〈0．01）;语言康复呈现明显的阶段发展规律。结论依据儿童语言发展的阶段规律,通过多角度评估和观察,合理制订术后语言康复教学目标,开展多种途径的语言康复教学活动,能够促进儿童人工耳蜗术后语言康复的效果。     

Tinnitus is prevalent in children with cochlear implants

Objectives

To explore the prevalence and the perceived impact of tinnitus in children using cochlear implants.

Method

Cross-sectional study of implanted children attending a cochlear implant family event organized annually by our academic tertiary pediatric care center. Children were interviewed together with their parents, using open-questioning and structured interview qualitative methodologies. The main outcome measures were the prevalence of tinnitus and any impact of these symptoms.

Results

40 children (age range: 3-15, mean: 7 years) and their families were interviewed. These included unilateral implantees (n = 21), and bilateral implantees (n = 19) whose two procedures were simultaneous (n = 6), within 6-12 months (n = 3), or >2 years apart (n = 10). Tinnitus was reported by 38% (n = 15). Tinnitus occurred most commonly in the implanted ear, when the implants were not in use (e.g. in bed at night). The children were generally untroubled by the tinnitus, although two reported difficulty sleeping. Tinnitus was most frequent in children aged 6-8 years (8/17, 47%), and in bilateral implantees with an inter-procedure delay of at least 2 years (6/10, 60%). Tinnitus was least reported in those implanted bilaterally simultaneously (1/6, 17%), and in those 5 years old or younger (3/11, 27%). No obvious relationship was identified between the prevalence of tinnitus and the etiology of deafness, age of implantation, or time elapsed since implantation.

Conclusions

To our knowledge this is the first study to report the widespread prevalence of tinnitus in implanted children. Further work, particularly examining the effect of inter-implant delay on tinnitus in bilateral implantees, may contribute to our understanding of the neuronal plasticity after implantation.     

An exploratory study of visual sequential processing in children with cochlear implants

ObjectiveThe objective of the study was to compare visual sequential processing in school-age children with cochlear implants (CIs) and their normal-hearing (NH) peers. Visual sequential processing was examined using both behavioral and an event-related potential (ERP) measures.MethodsEighteen children with CIs and nineteen children who had hearing within normal limits (NH) participated in the behavioral study. Subtests from the Test of Visual Perceptual Skills and the Sensory Integration and Praxis Test were administered to all children. ERP measures were collected from five children with CI and five age-matched peers. Peak latencies (N200 and P300) and reaction times for visual sequential processing were compared in these two groups.ResultsThe findings of the study revealed significant group differences in visual sequential memory and visuo-motor sequencing tasks suggesting that children with severe-profound hearing loss may have difficulties in visual sequential tasks. The study also revealed longer P300 latencies and longer reaction times for a visual sequential matching task in children with CI when compared to their NH peers suggesting slower or delayed processing of visual sequential stimuli.ConclusionsThis exploratory study involving behavioral and ERP measures showed that as a group, children with prelingual, severe-profound hearing loss who use CIs have difficulties with visual sequential processing. These findings may have implications for rehabilitation for children with hearing loss in the light of recent evidence that accurate and efficient processing of sequentially presented visual stimuli is important for language and reading outcomes.     

Lexical and semantic ability in groups of children with cochlear implants,language impairment and autism spectrum disorder

Objective

Lexical-semantic ability was investigated among children aged 6–9 years with cochlear implants (CI) and compared to clinical groups of children with language impairment (LI) and autism spectrum disorder (ASD) as well as to age-matched children with normal hearing (NH). In addition, the influence of age at implantation on lexical-semantic ability was investigated among children with CI.

Methods

97 children divided into four groups participated, CI (n = 34), LI (n = 12), ASD (n = 12), and NH (n = 39). A battery of tests, including picture naming, receptive vocabulary and knowledge of semantic features, was used for assessment. A semantic response analysis of the erroneous responses on the picture-naming test was also performed.

Results

The group of children with CI exhibited a naming ability comparable to that of the age-matched children with NH, and they also possessed a relevant semantic knowledge of certain words that they were unable to name correctly. Children with CI had a significantly better understanding of words compared to the children with LI and ASD, but a worse understanding than those with NH. The significant differences between groups remained after controlling for age and non-verbal cognitive ability.

Conclusions

The children with CI demonstrated lexical-semantic abilities comparable to age-matched children with NH, while children with LI and ASD had a more atypical lexical-semantic profile and poorer sizes of expressive and receptive vocabularies. Dissimilar causes of neurodevelopmental processes seemingly affected lexical-semantic abilities in different ways in the clinical groups.     

Inferences and metaphoric comprehension in unilaterally implanted children with adequate formal oral language performance

Objectives

To assess skills in inferences during conversations and in metaphors comprehension of unilaterally cochlear implanted children with adequate abilities at the formal language tests, comparing them with well-matched hearing peers; to verify the influence of age of implantation on overall skills.

Methods

The study was designed as a matched case–control study. 31 deaf children, unilateral cochlear implant users, with normal linguistic competence at formal language tests were compared with 31 normal hearing matched peers. Inferences and metaphor comprehension skills were assessed through the Implicit Meaning Comprehension, Situations and Metaphors subtests of the Italian Standardized Battery of “Pragmatic Language Skills MEDEA”. Differences between patient and control groups were tested by the Mann–Whitney U test. Correlations between age at implantation and time of implant use with each subtest were investigated by the Spearman rank correlation coefficient.

Results

No significant differences between the two groups were found in inferencing skills (p = 0.24 and p = 0.011 respectively for Situations and Implicit Meaning Comprehension). Regarding figurative language, unilaterally cochlear implanted children performed significantly below their normal hearing peers in Verbal Metaphor comprehension (p = 0.001). Performances were related to age at implantation, but not with time of implant use.

Conclusions

Unilaterally cochlear implanted children with normal language level showed responses similar to NH children in discourse inferences, but not in figurative language comprehension. Metaphors still remains a challenge for unilateral implant users and above all when they have not any reference, as demonstrated by the significant difference in verbal rather than figurative metaphors comprehension. Older age at implantation was related to worse performance for all items. These aspects, until now less investigated, had to receive more attention to deeply understand specific mechanisms involved and possible effects of different levels of figurative language complexity (presence or absence of contextual input, degree of transparency and syntactic frozenness). New insight is needed to orient programs in early intervention settings in considering and adequately responding to all these complex communicative need of children with hearing loss.     

Simultaneous cochlear implantation in children: the Great Ormond Street experience

Abstract

Objectives

To analyse the surgical aspects and safety of bilateral simultaneous cochlear implantation in children.

Methods

A retrospective case series at a tertiary paediatric centre in the United Kingdom. Surgical times, analgesia and antiemetic use, and complications were analysed for the first 25 bilateral simultaneous cochlear implants performed at Great Ormond Street Hospital for Children between September 2007 and December 2009. These were compared with a consecutive group of sequentially implanted children whose second implant was performed during the same period.

Results

Total time for simultaneous implantation was significantly less than the cumulative time required for sequential implantation (P < 0.05). In addition, the number of paracetamol, non-steroidal anti-inflammatory, and antiemetic doses was significantly less for simultaneous implantation than for sequential implantation (P < 0.001). Furthermore, the number of doses of analgesia and antiemetic required for simultaneous implantation were no higher than for single-side surgery (P > 0.05). No difference in complication rates was seen between the groups.

Discussion

Bilateral simultaneous cochlear implantation in children is safe and results in a reduction in total theatre time when compared with the cumulative time required for sequential implantation. Simultaneous implantation also reduces total analgesia and antiemetic requirements and length of stay to levels comparable with single-side implantation.     

Working memory in children with cochlear implants: Problems are in storage,not processing

Background

There is growing consensus that hearing loss and consequent amplification likely interact with cognitive systems. A phenomenon often examined in regards to these potential interactions is working memory, modeled as consisting of one component responsible for storage of information and another component responsible for processing of that information. Signal degradation associated with cochlear implants should selectively inhibit storage without affecting processing. This study examined two hypotheses: (1) A single task can be used to measure storage and processing in working memory, with recall accuracy indexing storage and rate of recall indexing processing; (2) Storage is negatively impacted for children with CIs, but not processing.

Method

Two experiments were conducted. Experiment 1 included adults and children, 8 and 6 years of age, with NH. Procedures tested the prediction that accuracy of recall could index storage and rate of recall could index processing. Both measures were obtained during a serial-recall task using word lists designed to manipulate storage and processing demands independently: non-rhyming nouns were the standard condition; rhyming nouns were predicted to diminish storage capacity; and non-rhyming adjectives were predicted to increase processing load. Experiment 2 included 98 8-year-olds, 48 with NH and 50 with CIs, in the same serial-recall task using the non-rhyming and rhyming nouns.

Results

Experiment 1 showed that recall accuracy was poorest for the rhyming nouns and rate of recall was slowest for the non-rhyming adjectives, demonstrating that storage and processing can be indexed separately within a single task. In Experiment 2, children with CIs showed less accurate recall of serial order than children with NH, but rate of recall did not differ. Recall accuracy and rate of recall were not correlated in either experiment, reflecting independence of these mechanisms.

Conclusions

It is possible to measure the operations of storage and processing mechanisms in working memory in a single task, and only storage is impaired for children with CIs. These findings suggest that research and clinical efforts should focus on enhancing the saliency of representation for children with CIs. Direct instruction of syntax and semantics could facilitate storage in real-world working memory tasks.     

Vocal singing by prelingually-deafened children with cochlear implants

The coarse pitch information in cochlear implants might hinder the development of singing in prelingually-deafened pediatric users. In the present study, seven prelingually-deafened children with cochlear implants (5.4–12.3 years old) sang one song that was the most familiar to him or her. The control group consisted of 14 normal-hearing children (4.1–8.0 years old). The fundamental frequencies (F0) of each note in the recorded songs were extracted. The following five metrics were computed based on the reference music scores: (1) F0 contour direction of the adjacent notes, (2) F0 compression ratio of the entire song, (3) mean deviation of the normalized F0 across the notes, (4) mean deviation of the pitch intervals, and (5) standard deviation of the note duration differences. Children with cochlear implants showed significantly poorer performance in the pitch-based assessments than the normal-hearing children. No significant differences were seen between the two groups in the rhythm-based measure. Prelingually-deafened children with cochlear implants have significant deficits in singing due to their inability to manipulate pitch in the correct directions and to produce accurate pitch height. Future studies with a large sample size are warranted in order to account for the large variability in singing performance.     

Behavioral inhibition and clinical outcomes in children with cochlear implants

OBJECTIVES/HYPOTHESIS: Individual speech and language outcomes of deaf children with cochlear implants (CIs) are quite varied. Individual differences in underlying cognitive functions may explain some of this variance. The current study investigated whether behavioral inhibition skills of deaf children were related to performance on a range of audiologic outcome measures. DESIGN: Retrospective analysis of longitudinal data collected from prelingually and profoundly deaf children who used CIs. METHODS: Behavioral inhibition skills were measured using a visual response delay task that did not require hearing. Speech and language measures were obtained from behavioral tests administered at 1-year intervals of CI use. RESULTS: Female subjects showed higher response delay scores than males. Performance increased with length of CI use. Younger children showed greater improvement in performance as a function of device use than older children. No other subject variable had a significant effect on response delay score. A series of multiple regression analyses revealed several significant relations between delay task performance and open set word recognition, vocabulary, receptive language, and expressive language scores. CONCLUSIONS: The present results suggest that CI experience affects visual information processing skills of prelingually deaf children. Furthermore, the observed pattern of relations suggests that speech and language processing skills are closely related to the development of response delay skills in prelingually deaf children with CIs. These relations may reflect underlying verbal encoding skills, subvocal rehearsal skills, and verbally mediated self-regulatory skills. Clinically, visual response delay tasks may be useful in assessing behavioral and cognitive development in deaf children after implantation.     

UK and Ireland experience of cochlear implants in children with Down Syndrome

Objectives

Down Syndrome (DS) is associated with a high incidence of hearing loss. The majority of hearing loss is conductive, but between 4 and 20% is sensorineural, which in the main is mild or moderate and is managed with conventional behind-the-ear hearing aids. Cochlear implantation is an elective invasive procedure, performed to provide some form of hearing rehabilitation in individuals with severe to profound sensorineural hearing loss, and initially candidacy criteria were strict—excluding patients with additional disabilities. With good results and expanding experience, more candidates with additional disabilities are now being implanted. A survey of UK and Ireland Cochlear Implant Programmes sought to identify the number of individuals with DS who have been implanted with a cochlear implant (CI) and to provide relevant information on outcomes of implantation in these individuals.

Methods

E-mail survey of all programmes within the British Cochlear Implant Group (BCIG). Postal questionnaire to programmes identified to have implanted a child with Down Syndrome, with data collection on pre-operative assessment, surgical and post-operative outcomes. Case series review.

Results

Three of 23 BCIG programmes have implanted a child with Down Syndrome. Four children have received implants. No intraoperative or post-operative surgical complications were encountered. All children had middle ear disease, but no problems with implantation were associated with their middle ear condition. All children remain implant users, 12 months to 4 years post-implantation.

Conclusion

Cochlear implantation is an option for a child with Down Syndrome and associated severe to profound sensorineural hearing loss. Clinicians caring for these children and their families should consider referral for assessment by a Cochlear Implant Programme.     

Development of auditory and language skills in children using cochlear implants with two signal processing strategies

IntroductionThe increase in the spectral information offered by the sound processing strategy HiRes 120 has led to great expectations for the pediatric population. Due to a shorter duration of auditory deprivation and higher neural plasticity, children could benefit more substantially from the spectral information of this sound processing strategy.ObjectiveTo compare auditory and language skills in Brazilian children with cochlear implants using the HiRes and HiRes 120 sound processing strategies.MethodsThirty children, aged 1–3 years, with congenital hearing loss, were divided into two groups, according to the signal processing strategy adjusted at the time of the cochlear implant activation. The assessed children were matched according to chronological age and the time of the cochlear implant use. The auditory and language skills were evaluated longitudinally through the Infant-Toddler Meaningful Auditory Integration Scale and Production Infant Scale Evaluation, carried out before surgery, and 3, 6 and 12 months after device implantation. The Mann–Whitney test was applied for the comparison between the two groups with a 5% significance level.ResultsThe findings indicated development of hearing and language skills in the first year of cochlear implant use; however, there was no statistically significant difference in the evolution of such skills due to the adjusted processing strategy in the activation of the cochlear implant electrodes.ConclusionThe development of auditory and language skills in the assessed children was similar during the entire study period, regardless of which signal processing strategy was used.     

Incidence and characteristics of facial nerve stimulation in children with cochlear implants

OBJECTIVES: Electrical stimulation from a cochlear implant can spread beyond the auditory nerve. The aims of this study were to accurately measure facial nerve stimulation in pediatric implant users and to determine the characteristics and incidence of this unwanted activity. Part A consisted of a prospective study of a randomized sample of 44 pediatric implant users. Part B consisted of a retrospective analysis of 121 children with previously recorded electrically evoked auditory brainstem responses (EABR). STUDY DESIGN AND METHODS: Responses were evoked by 3 electrodes along the implant array in three groups of children: 1) postmeningitic, 2) abnormal cochlea, and 3) neither. Intraoperative measures were obtained under anesthesia; all other recordings were completed in awake children. RESULTS: Intraoperative recordings revealed large nonauditory responses in a number of channels, including the midline EABR. Under paralysis, these responses disappeared, and clear EABRs were recorded. Similarly, prospective postoperative electromyographic (EMG) responses from the facial nerve were found in more than 59% (26 of 44) of experienced implant users (Nucleus 24): 31% of postmeningitic children (4 of 13), 80% of those with abnormal cochlea (8 of 10), and 66% of those with neither (14 of 21). Retrospective analysis of previously recorded postoperative EABRs demonstrated facial nerve stimulation in 35% (42 of 121). In most cases, facial nerve stimulation occurred when levels were perceptually loud but comfortable. CONCLUSIONS: 1) Facial nerve potentials can be recorded using EMG in a large proportion of cochlear implant users at high levels of stimulation. 2) The EABR can be obscured in the presence of facial nerve stimulation and care should be taken to distinguish it from the EMG response, particularly when auditory brainstem activity is in question. 3) Use of surface EMG provides an additional objective measure to ensure the safe and comfortable use of cochlear implants.     

Lexical tone recognition in noise in normal-hearing children and prelingually deafened children with cochlear implants

Abstract

Objective: The purpose of the present study was to investigate Mandarin tone recognition in background noise in children with cochlear implants (CIs), and to examine the potential factors contributing to their performance. Design: Tone recognition was tested using a two-alternative forced-choice paradigm in various signal-to-noise ratio (SNR) conditions (i.e. quiet,?+12,?+6, 0, and ?6?dB). Linear correlation analysis was performed to examine possible relationships between the tone-recognition performance of the CI children and the demographic factors. Study sample: Sixty-six prelingually deafened children with CIs and 52 normal-hearing (NH) children as controls participated in the study. Results: Children with CIs showed an overall poorer tone-recognition performance and were more susceptible to noise than their NH peers. Tone confusions between Mandarin tone 2 and tone 3 were most prominent in both CI and NH children except for in the poorest SNR conditions. Age at implantation was significantly correlated with tone-recognition performance of the CI children in noise. Conclusions: There is a marked deficit in tone recognition in prelingually deafened children with CIs, particularly in noise listening conditions. While factors that contribute to the large individual differences are still elusive, early implantation could be beneficial to tone development in pediatric CI users.