Duration Of Cochlear Implant Use Research Articles

Influence of Speech Rate on Auditory Recognition in Cochlear Implant Users

Introduction: This study aimed to verify the influence of speech stimulus presentation and speed on auditory recognition in cochlear implant (CI) users with poorer performance. Methods: The cross-sectional observational study applied auditory speech perception tests to fifteen adults, using three different ways of presenting the stimulus, in the absence of competitive noise: monitored live voice (MLV); recorded speech at typical speed (RSTS); recorded speech at slow speed (RSSS). The scores were assessed using the Percent Sentence Recognition Index (PSRI). The data were inferentially analysed using the Friedman and Wilcoxon tests with a 95% confidence interval and 5% significance level (p < 0.05). Results: The mean age was 41.1 years, the mean duration of CI use was 11.4 years, and the mean hearing threshold was 29.7 ± 5.9 dBHL. Test performance, as determined by the PSRI, was MLV = 42.4 ± 17.9%; RSTS = 20.3 ± 14.3%; RSSS = 40.6 ± 20.7%. There was a significant difference identified for RSTS compared to MLV and RSSS. Conclusion: The way the stimulus is presented and the speed at which it is presented enable greater auditory speech recognition in CI users, thus favouring comprehension when the tests are applied in the MLV and RSSS modalities.

A cortical biomarker of audibility and processing efficacy in children with single-sided deafness using a cochlear implant

The goals of the current study were to evaluate audibility and cortical speech processing, and to provide insight into binaural processing in children with single-sided deafness (CHwSSD) using a cochlear implant (CI). The P1 potential to acoustically-presented speech stimuli (/m/, /g/, /t/) was recorded during monaural [Normal hearing (NH), CI], and bilateral (BIL, NH + CI) listening conditions within a clinical setting in 22 CHwSSD (mean age at CI/testing 4.7, 5.7 years). Robust P1 potentials were elicited in all children in the NH and BIL conditions. In the CI condition: (1) P1 prevalence was reduced yet was elicited in all but one child to at least one stimulus; (2) P1 latency was prolonged and amplitude was reduced, consequently leading to absence of binaural processing manifestations; (3) Correlation between P1 latency and age at CI/testing was weak and not significant; (4) P1 prevalence for /m/ was reduced and associated with CI manufacturer and duration of CI use. Results indicate that recording CAEPs to speech stimuli in clinical settings is feasible and valuable for the management of CHwSSD. While CAEPs provided evidence for effective audibility, a substantial mismatch in timing and synchrony of early-stage cortical processing between the CI and NH ear remains a barrier for the development of binaural interaction components.

Sustainable Benefits of High Variability Phonetic Training in Mandarin-speaking Kindergarteners With Cochlear Implants: Evidence From Categorical Perception of Lexical Tones.

Although pitch reception poses a great challenge for individuals with cochlear implants (CIs), formal auditory training (e.g., high variability phonetic training [HVPT]) has been shown to provide direct benefits in pitch-related perceptual performances such as lexical tone recognition for CI users. As lexical tones in spoken language are expressed with a multitude of distinct spectral, temporal, and intensity cues, it is important to determine the sources of training benefits for CI users. The purpose of the present study was to conduct a rigorous fine-scale evaluation with the categorical perception (CP) paradigm to control the acoustic parameters and test the efficacy and sustainability of HVPT for Mandarin-speaking pediatric CI recipients. The main hypothesis was that HVPT-induced perceptual learning would greatly enhance CI users' ability to extract the primary pitch contours from spoken words for lexical tone identification and discrimination. Furthermore, individual differences in immediate and long-term gains from training would likely be attributable to baseline performance and duration of CI use. Twenty-eight prelingually deaf Mandarin-speaking kindergarteners with CIs were tested. Half of them received five sessions of HVPT within a period of 3 weeks. The other half served as control who did not receive the formal training. Two classical CP tasks on a tonal continuum from Mandarin tone 1 (high-flat in pitch) to tone 2 (mid-rising in pitch) with fixed acoustic features of duration and intensity were administered before (pretest), immediately after (posttest), and 10 weeks posttraining termination (follow-up test). Participants were instructed to either label a speech stimulus along the continuum (i.e., identification task) or determine whether a pair of stimuli separated by zero or two steps from the continuum was the same or different (i.e., discrimination task). Identification function measures (i.e., boundary position and boundary width) and discrimination function scores (i.e., between-category score, within-category score, and peakedness score) were assessed for each child participant across the three test sessions. Linear mixed-effects (LME) models showed significant training-induced enhancement in lexical tone categorization with significantly narrower boundary width and better between-category discrimination in the immediate posttest over pretest for the trainees. Furthermore, training-induced gains were reliably retained in the follow-up test 10 weeks after training. By contrast, no significant changes were found in the control group across sessions. Regression analysis confirmed that baseline performance (i.e., boundary width in the pretest session) and duration of CI use were significant predictors for the magnitude of training-induced benefits. The stringent CP tests with synthesized stimuli that excluded acoustic cues other than the pitch contour and were never used in training showed strong evidence for the efficacy of HVPT in yielding immediate and sustained improvement in lexical tone categorization for Mandarin-speaking children with CIs. The training results and individual differences have remarkable implications for developing personalized computer-based short-term HVPT protocols that may have sustainable long-term benefits for aural rehabilitation in this clinical population.

Preoperative Reading Efficiency as a Predictor of Adult Cochlear Implant Outcomes.

1) Scores of reading efficiency (the Test of Word Reading Efficiency, second edition) obtained in adults before cochlear implant surgery will be predictive of speech recognition outcomes 6 months after surgery; and 2) Cochlear implantation will lead to improvements in language processing as measured through reading efficiency from preimplantation to postimplantation. Adult cochlear implant (CI) users display remarkable variability in speech recognition outcomes. "Top-down" processing-the use of cognitive resources to make sense of degraded speech-contributes to speech recognition abilities in CI users. One area that has received little attention is the efficiency of lexical and phonological processing. In this study, a visual measure of word and nonword reading efficiency-relying on lexical and phonological processing, respectively-was investigated for its ability to predict CI speech recognition outcomes, as well as to identify any improvements after implantation. Twenty-four postlingually deaf adult CI candidates were tested on the Test of Word Reading Efficiency, Second Edition preoperatively and again 6 months post-CI. Six-month post-CI speech recognition measures were also assessed across a battery of word and sentence recognition. Preoperative nonword reading scores were moderately predictive of sentence recognition outcomes, but real word reading scores were not; word recognition scores were not predicted by either. No 6-month post-CI improvement was demonstrated in either word or nonword reading efficiency. Phonological processing as measured by the Test of Word Reading Efficiency, Second Edition nonword reading predicts to a moderate degree 6-month sentence recognition outcomes in adult CI users. Reading efficiency did not improve after implantation, although this could be because of the relatively short duration of CI use.

Children with cochlear implant and additional disabilities benefit from consistent device use.

Although the prevalence of additional disabilities (AD) in children with a cochlear implant (CI) is high, children with such disabilities are often excluded from clinical studies, or their specific characteristics are only partially included. The literature shows that several factors need to be considered in evaluating auditory and language development in CI children with AD, including demographic variables as well as the severity and type of disability. Current findings on device use in children show correlations with auditory and language outcome, but little is known about device use specifically in children with AD. The purpose of this study was to determine the auditory and language outcome of CI children with AD and to analyse their datalogging-based daily device use, both 1 year and 2 years after implantation. In addition, any potential correlations between outcome and device use were to be identified. A cohort of 32 CI children with 5 different types of AD were included in this retrospective analysis. The children's auditory and language outcome was assessed by the parental questionnaires LittlEARS and ELFRA and by the professional observation tool CAP (Categories of Auditory Performance) 1 and 2 years after implantation. Longitudinal device use was analysed by using the CI system-integrated data-logging; daily duration of CI use, number of coil disconnections and exposure to different listening scenes were recorded. Overall, the cohort's auditory and language performance showed significant progress over time, while reduced abilities became more obvious after 2 years of CI experience. The mean daily duration of CI use increased significantly from 7.8±2.8 to 8.2±2.7h after 2 years. High numbers of daily coil disconnections were detected, with a significant mean decrease from 83.4±73.1 to 66.3±54.6 whereas the percentage exposure to different listening environments was widely stable over time. Significant rank correlations were identified between outcomes measured by ELFRA and CAP with daily duration of CI use, numbers of coil disconnections and percentage of exposure to speech-characterised listening scenes. The auditory and language outcome in CI children with AD is variable, but it progresses over time. Children benefit from a consistent daily device use as well as from a high exposure to speech-characterised environments. Device use should be monitored constantly, with particular focus on daily duration of CI use and, in particular, on the number of coil disconnections if children have a severe motor impairment. Objective data-logging is an important addition to outcome assessment by testing, observations and parental questionnaires. Although assessment in children with AD is a major challenge for professionals, comprehensive assessment is needed to improve cochlear implant services with special adaption to children with AD, and this should include audiological, development-related and psychosocial information. A unified system to classify types of disabilities could help to improve procedures for analysing different outcomes.

MELUDIA – Online music training for cochlear implant users

Background Music enjoyment is of importance for many cochlear implant (CI) users, and the interest in music training is high. But many CI users report that it is a challenge to find suitable training resources and that they stall because they don’t know how to practice. Meludia is an online music training program that provides structured and guided music training for musically experienced and inexperienced children and adults. Objective The aim of the study was to evaluate the suitability of the Meludia music training software for CI recipients based on two research questions: (1) are the easiest exercises available easy enough for CI users, and (2) are there any gaps when progressing through levels and stars with increasing difficulty? Methods Thirty-eight adult MED-EL CI users completed fourteen exercises involving 5 different musical dimensions of the online music training program. Results Our results show that the easiest exercises available in Meludia are easy enough for CI users to be able to use this training resource independent of age, indication, duration of CI use or musical background. Conclusion With Meludia we assessed and found a suitable and comprehensive training tool that allows CI recipients to work on individual goals regardless of their present abilities.

Sound Source Localization by Cochlear Implant Recipients with Normal Hearing in the Contralateral Ear: Effects of Spectral Content and Duration of Listening Experience

Introduction: Cochlear implant (CI) recipients with normal hearing (NH) in the contralateral ear experience a significant improvement in sound source localization when listening with the CI in combination with their NH-ear (CI + NH) as compared to with the NH-ear alone. The improvement in localization is primarily due to sensitivity to interaural level differences (ILDs). Sensitivity to interaural timing differences (ITDs) may be limited by auditory aging, frequency-to-place mismatches, the signal coding strategy, and duration of CI use. The present report assessed the sensitivity of ILD and ITD cues in CI + NH listeners who were recipients of long electrode arrays that provide minimal frequency-to-place mismatches and were mapped with a coding strategy that presents fine structure cues on apical channels. Methods: Sensitivity to ILDs and ITDs for localization was assessed using broadband noise (BBN), as well as high-pass (HP) and low-pass (LP) filtered noise for adult CI + NH listeners. Stimuli were 200-ms noise bursts presented from 11 speakers spaced evenly over an 180° arc. Performance was quantified in root-mean-squared error and response patterns were analyzed to evaluate the consistency, accuracy, and side bias of the responses. Fifteen listeners completed the task at the 2-year post-activation visit; seven listeners repeated the task at a later annual visit. Results: Performance at the 2-year visit was best with the BBN and HP stimuli and poorer with the LP stimulus. Responses to the BBN and HP stimuli were significantly correlated, consistent with the idea that CI + NH listeners primarily use ILD cues for localization. For the LP stimulus, some listeners responded consistently and accurately and with limited side bias, which may indicate sensitivity to ITD cues. Two of the 7 listeners who repeated the task at a later annual visit experienced a significant improvement in performance with the LP stimulus, which may indicate that sensitivity to ITD cues may improve with long-term CI use. Conclusions: CI recipients with a NH-ear primarily use ILD cues for sound source localization, though some may use ITD cues as well. Sensitivity to ITD cues may improve with long-term CI listening experience.

Just-Noticeable Differences of Fundamental Frequency Change in Mandarin-Speaking Children with Cochlear Implants.

Fundamental frequency (F0) provides the primary acoustic cue for lexical tone perception in tonal languages but remains poorly represented in cochlear implant (CI) systems. Currently, there is still a lack of understanding of sensitivity to F0 change in CI users who speak tonal languages. In the present study, just-noticeable differences (JNDs) of F0 contour and F0 level changes in Mandarin-speaking children with CIs were measured and compared with those in their age-matched normal-hearing (NH) peers. Results showed that children with CIs demonstrated significantly larger JND of F0 contour (JND-C) change and F0 level (JND-L) change compared to NH children. Further within-group comparison revealed that the JND-C change was significantly smaller than the JND-L change among children with CIs, whereas the opposite pattern was observed among NH children. No significant correlations were seen between JND-C change/JND-L change and age at implantation /duration of CI use. The contrast between children with CIs and NH children in sensitivity to F0 contour and F0 level change suggests different mechanisms of F0 processing in these two groups as a result of different hearing experiences.

Establishment of Reference Values for Early Auditory Preverbal Skills of Children with Cochlear Implants.

Auditory and verbal abilities of children with early cochlear implant (CI) surgery usually take some time to develop, and a reference index of early development for horizontal comparisons is urgently needed to guide the mapping process and adjust rehabilitation programs. Therefore, the aim of this study was to establish a reference value for early auditory preverbal skills development in children with CI and investigate the developmental curve and influencing factors for these children. The LittlEARS® Auditory Questionnaire (LEAQ) scores of 287 eligible Chinese participants were obtained at 1, 2, 3, 6, 9, 12, 18, 24, 28, and 36 months interval after CI activation. The median and standard deviation of the LEAQ score of each hearing stage for these children with different activation ages were calculated to establish the reference values. Quadratic regression was conducted to fit the expected developmental curve of the LEAQ score ( [0 to 20 months]). With a linear mixed-effects model, we found that the receptive auditory behavior increased rapidly after CI activation, while expressive language skills developed at a steady rate. We also found that the following factors all significantly influenced the LEAQ: the duration of CI use, the development quotient, age of implantation and activation, and the presence of large vestibular aqueduct syndrome or auditory neuropathy spectrum disorder. The reference values and the expected developmental curve for the LEAQ in children with CI established by the present study provides guidance to clinicians and parents as well as realistic expectations regarding language and speech outcomes.

A Meta-analysis of Language Abilities and Executive Function for Children with Cochlear Implants

The purpose of this study was to identify the differences in language ability and executive functions of children with cochlear implants (CI) and their peer normal hearing (NH) children, and to find out whether the auditory history (duration of CI use, age at implantation) of CI group plays a role as a moderator in controlling the effect size of the differences of the CI and NH groups. A total of 77 articles were searched, 11 studies which met the inclusive and exclusive criteria were selected from three electronic databases (Academic Search Complete, PsycInfo, PubMed). As a result, significant differences were identified in language ability and the five executive function subtypes (working memory, inhibition, shifting, emotion control, and sustained sequential processing) between two groups. But, the hearing history of CI group (duration of CI use, age at implantation) did not appear as a significant moderator. In conclusion, CI children’s language ability and executive function should be precisely monitored and regularly evaluated. In addition, we discussed the possibility that some executive function abilities (plan/organize, attention, and visuo-spatial organization) will remain in CI group. For the follow-up study, we need to identify various factors that support the CI children.

False Belief Understanding in Deaf Children With Cochlear Implants.

Theory of mind (ToM) is crucial for social interactions. Previous research has indicated that deaf and hard-of-hearing children born into hearing families (DoH) are at risk of delayed ToM development. However, it is unclear whether this is the case for DoH children who receive cochlear implants (CIs) before and around the second year of life. The present study aimed to investigate false belief understanding (FBU) in DoH children with CIs. The relationships between false belief task (FBT) performance, sentence comprehension, age at implantation, duration of CI use, and Speech Recognition Threshold were explored. A total of 94 children with typical levels of hearing (TH) and 45 DoH children (age range: 3–8), who received their first CI between 6 and 27 months of age, were tested on the FBT and a sentence comprehension test. Results showed that 4- and 5-year-old children with CIs performed significantly worse than their peers with TH on the FBT; 6- to 8-year-old children with CIs performed similarly to age-matched children with TH. Age at implantation and duration of CI use were correlated with sentence comprehension but not with the FBT. The results indicated that FBU was delayed until the age of 6 years in most of children with CIs.

Age-related language performance and device use in children with very early bilateral cochlear implantation

ObjectivesPaediatric cochlear implantation within the first year of life results in better outcome in auditory and language skills. Beside individual, audiological and social factors, quantity and quality of daily cochlear implant (CI) use also seem to be an influencing factor. The purpose of this study was to evaluate children's early receptive and expressive language performance considering bilingual language development as well as quantity and quality of daily CI use and intraoperative objective measurements. MethodsThe retrospective analysis included data from 35 very early bilaterally cochlear-implanted children (age at CI M = 8.4 ± 1.5 months). Language performance was assessed by the German standardised test SETK-2 (age at testing M = 29.4 ± 4.0 months). The CI system-integrated data-logging was analysed with regard to daily CoilOn-time, CoilOff and exposure to classified listening scenes. Intraoperatively measured thresholds of evoked compound action potentials (T-ECAPs) were analysed to ensure CI functionality. ResultsThe cohort showed language performance within the normal range for word comprehension, sentence comprehension and word production, level of sentence production was reduced. Overall, bilingual children performed less well than monolingual children. Intraoperative T-ECAPs were recorded for the total cohort and no anomalies were detected. Children used their CI for about 8.7 ± 1.4 h per day, most of this time spent in a quiet environment (38%). Word production was significantly correlated with the daily duration of CI use (CoilOn-time) and with exposure to the listening environment Speech. No correlation was found between number of daily coil disconnections (CoilOff) and language performance. ConclusionVery early bilateral cochlear implantation may result in age-appropriate language skills already at the age of 2 years. Monolingualism seems to a better condition for early language development with CI than bilingualism. Especially for word production, the daily duration of CI use and exposure time in a speech-characterised environment seem to be additional positive factors. Monitoring the data-logs should be one important focus of professionals during the postoperative rehabilitation process to detect potential benefits and risks. These findings should be integrated into rehabilitative therapy and parent counselling.

Assessment of Reliability and Validity of the Cochlear Implant Skills Review: A New Measure to Evaluate Cochlear Implant Users' Device Skills and Knowledge.

Purpose The Cochlear Implant Skills Review (CISR) was developed as a measure of cochlear implant (CI) users' skills and knowledge regarding device use. This study aimed to determine intra- and interrater reliability and agreement and establish construct validity for the CISR. Method In this study, the CISR was developed and administered to a cohort of 30 adult CI users. Participants included new CI users with less than 1 year of CI experience and experienced CI users with greater than 1 year of CI experience. The CISR administration required participants to demonstrate skills using the various features of their CI processors. Intra- and interrater reliability were assessed using intraclass correlation coefficients, agreement was assessed using Cohen's kappa, and construct validity was assessed by relating CISR performance to duration of CI use. Results Overall reliability for the entire instrument was 92.7%. Inter- and intrarater agreement were generally substantial or higher. Duration of CI use was a significant predictor of CISR performance. Conclusions The CISR is a reliable and valid assessment measure of device skills and knowledge for adult CI users. Clinicians can use this tool to evaluate areas of needed instruction and counseling and to assess users' skills over time.

Acoustic Assessment of Tone Production of Prelingually-Deafened Mandarin-Speaking Children With Cochlear Implants.

ObjectiveThe purpose of the present study was to investigate Mandarin tone production performance of prelingually deafened children with cochlear implants (CIs) using modified acoustic analyses and to evaluate the relationship between demographic factors of those CI children and their tone production ability.MethodsTwo hundred seventy-eight prelingually deafened children with CIs and 173 age-matched normal-hearing (NH) children participated in the study. Thirty-six monosyllabic Mandarin Chinese words were recorded from each subject. The fundamental frequencies (F0) were extracted from the tone tokens. Two acoustic measures (i.e., differentiability and hit rate) were computed based on the F0 onset and offset values (i.e., the tone ellipses of the two-dimensional [2D] method) or the F0 onset, midpoint, and offset values (i.e., the tone ellipsoids of the 3D method). The correlations between the acoustic measures as well as between the methods were performed. The relationship between demographic factors and acoustic measures were also explored.ResultsThe children with CIs showed significantly poorer performance in tone differentiability and hit rate than the NH children. For both CI and NH groups, performance on the two acoustic measures was highly correlated with each other (r values: 0.895–0.961). The performance between the two methods (i.e., 2D and 3D methods) was also highly correlated (r values: 0.774–0.914). Age at implantation and duration of CI use showed a weak correlation with the scores of acoustic measures under both methods. These two factors jointly accounted for 15.4–18.9% of the total variance of tone production performance.ConclusionThere were significant deficits in tone production ability in most prelingually deafened children with CIs, even after prolonged use of the devices. The strong correlation between the two methods suggested that the simpler, 2D method seemed to be efficient in acoustic assessment for lexical tones in hearing-impaired children. Age at implantation and especially the duration of CI use were significant, although weak, predictors for tone development in pediatric CI users. Although a large part of tone production ability could not be attributed to these two factors, the results still encourage early implantation and continual CI use for better lexical tone development in Mandarin-speaking pediatric CI users.

Quantitative assessment of temporal skin elasticity using shear wave elastography in pediatric cochlear implant users

ObjectiveTo evaluate temporal skin thicknesses and stiffness values using shear wave elastography (SWE) in asymptomatic pediatric patients who underwent cochlear implantation. Subjects and methodsSixty-four deafened pediatric patients with unilateral cochlear implant (CI) who had no complications were enrolled. The age, sex, weight, height, body mass index (BMI), CI side, duration of CI use and CI device brand of all participants were noted. Temporal skin thickness and stiffness values were measured from implanted and contralateral unimplanted sides using SWE. ResultsThe mean skin thickness measurements of implanted and unimplanted sides were 11.87 ± 3.42 and 5.34 ± 1.56 mm, respectively. The mean skin stiffness measurements of implanted and unimplanted sides were 3.08 ± 0.7 and 1.29 ± 0.26 m/s, respectively. There were statistically significant differences in skin thickness and stiffness between implanted and unimplanted sides (P < .001, P < .001). The mean skin thickness and stiffness measurements did not differ among types of CI devices (P = .948, P = .362). Age had positive correlation with implanted (P < .001, P = .019) and unimplanted sides (P < .001, P < .001) skin thickness and stiffness. BMI had positive correlation with implanted (P < .001, P = .023) and unimplanted sides (P < .001, P < .001) skin thickness and stiffness. Duration of CI use had positive correlation with implanted side skin thickness (P < .001) and stiffness (P = .031). ConclusionTemporal skin thickness and stiffness increase after CI surgery. SWE has the potential to improve diagnostic accuracy, and our results may provide important data for evaluation of clinical entities that affect temporal skin structures.

Psychoacoustic and Demographic Factors for Speech Recognition of Older Adult Cochlear Implant Users.

Purpose This study aimed to evaluate the effects of aging and cochlear implant (CI) on psychoacoustic and speech recognition abilities and to assess the relative contributions of psychoacoustic and demographic factors to speech recognition of older CI (OCI) users. Method Twelve OCI users, 12 older acoustic-hearing (OAH) listeners age-matched to OCI users, and 12 younger normal-hearing (YNH) listeners underwent tests of temporal amplitude modulation detection, temporal gap detection in noise, and spectral-temporal modulated ripple discrimination. Speech reception thresholds were measured for sentence recognition in multitalker, speech-babble noise. Results Statistical analyses showed that, for the small sample of OAH listeners, the degree of hearing loss did not significantly affect any outcome measure. Temporal resolution, spectral resolution, and speech recognition all significantly degraded with both age and the use of a CI (i.e., YNH better than OAH and OAH better than OCI performance). Although both were significantly correlated with OCI users' speech recognition, the duration of CI use no longer had a significant effect on speech recognition once the effect of spectral-temporal ripple discrimination performance was taken into account. For OAH listeners, the only significant predictor of speech recognition was temporal gap detection performance. Conclusion The preliminary results suggest that speech recognition of OCI users may improve with longer duration of CI use, mainly due to higher perceptual acuity to spectral-temporal modulated ripples in acoustic stimuli.

The influence of age and language on developmental trajectory of theory of mind in children with cochlear implants

ObjectiveThe present study investigates if children with cochlear implants (CI) are associated with delayed development of Theory of Mind (ToM) and the differences in gain of ToM ability with respect to age, language and other aspects of CI. MethodsOne-hundred-eleven children with participation of their hearing parents, aged between 36 months and 132 months, who had congenital profound bilateral deafness and were unilateral CI users; plus 99 healthy children underwent ‘Peabody Picture Vocabulary’ and ‘Sally-Anne’ tests. A total of 77 children with CI (mean age: 76.51 months, 31 girls and 46 boys) and 82 healthy children (mean age: 72.41 months, 47 girls and 35 boys) were included in the analyses. Analytic comparisons were created between the controls and children with CI and between subgroups of CI users by univariate and multivariate analysis. The effects of age of hearing aid use, age of CI surgery, duration of CI use, language scores and the presence of risk factors, early rehabilitation with hearing aid and CI on the ToM development were analyzed. ResultsThe Sally-Anne test success rates of 67.1% were significantly higher in controls than that of children with CI (49.4%) (p < 0.05). The mean age difference of the children, who were successful in Sally-Anne test was 5.33 months in favor of healthy controls. The ToM task success rates were 57.1% (24/42) and 40% (14/35) in children with early CI and late CI respectively. The children, who were good at language, were also better in Sally-Anne tests, but the mean Peabody Picture Vocabulary test scores were indifferent in the same age group with respect to the presence of CI use (p > 0.05). However, multivariate analysis presented the higher language scores as the only significant independent variable that has impact on the success in Sally-Anne test (p < 0.05). ConclusionThe results revealed that among all children, who did better in ToM were older in age and better in language skills. Children with CI also performed better in false-belief test depending on their language scores. Early CI surgery, older age, and hence longer CI use can provide a well-developed ToM for children with CI.

Speech Perception, Dichotic Listening, and Ear Advantage in Simultaneous Bilateral Cochlear Implanted Children

To study the development of dichotic listening, ear advantage, and speech perception in cochlear implant (CI) recipients using five audiometric tests. Prospective cohort analysis. University Hospital. One hundred twenty one participants who received simultaneous bilateral CIs and had at least 12 months of regular bilateral CI use. Age at time of testing ranged from 4 to 18 years with a mean age of 9 years (standard deviation [SD]: 3.0). Mean duration of CI use was 7.073 years (SD: 2.86). Bilateral simultaneous cochlear implantation. Goettinger and Freiburger monosyllabic word test, Hochmair, Schulz and Desoyer sentence (HSM) test in noise and in quiet conditions and the dichotic listening test by Uttenweiler were applied according to the childrens' age. The results were evaluated using a two-sided t test for dependent samples. In all tests applied, we could not show significant differences in performance between left and right CI and therefore could not demonstrate an ear advantage. Dichotic listening was challenging, only one subject produced results required for normal hearing subjects to pass the test. The older the CI recipients get and duration of CI use increases, the more results in all speech perception tests improve. Our results cannot lend further support to the existence of ear advantage in CI recipients. We do not recommend the Uttenweiler dichotic listening test to determine lateralization. Further research to gather more information on dichotic listening and ear advantage in CI recipients is necessary and should use consonant-vowel stimuli as more comparable stimuli.

Restoration of auditory network after cochlear implant in prelingual deafness: a P300 study using LORETA.

SUMMARYThe concept of auditory restoration after cochlear implant (CI) in prelingual deafness is well described by a synaptic network model, whose development depends on sensory experience. The aim of this work was to study the associative networks activated by the CI in a population of prelingually deaf patients. In particular, the impact of age at time of first CI fitting and duration of CI use was evaluated. Twenty patients were tested and divided into three groups: early implanted and lengthy CI use (group A); late implanted and lengthy CI use (group B); late implanted and short CI use (group C). Each patient group was compared with a normal hearing age matched control group. All subjects underwent to auditory event-related potentials (ERPs) registration. ERP latencies and their cortical sources were investigated. Cortical source analysis was performed using LORETA (Low Resolution Electromagnetic Tomography) software. P300 latencies were significantly longer in patients than in controls. The amount of cortical activation was found to be significantly directly correlated with duration of implant use and significantly correlated inversely with age at implant. When comparing patients and controls, comparable cortical activation was only found in A patient group, and to a lesser extent in group B, while significantly lower activation was found in patient group C in the frontal and cingulate areas. CI adds a sensory modality in deafness patients, i.e. the auditory one. This involves areas implicated in sensory and cognitive functions, and needs some time to form. The duration of CI use is crucial: our results demonstrate the importance of long term use of the device in addition to an early time of implant.

Health-related quality of life in South African children who use cochlear implants

Objective: To describe health-related quality of life (HRQoL) outcomes of school-going paediatric cochlear implant (CI) recipients in a South African cohort from the perspectives of parents.Design: Parents of school-going CI recipients completed the Children with Cochlear Implants: Parental Perspectives (CCIPP) CI-specific HRQoL questionnaire. The effect of different demographic variables on HRQoL outcomes was also determined.Study sample: The study sample included 54 parents of school-going (mean age = 12.2 years; SD = 3.6; range = 6.6–18.3 years) CI recipients with at least six months CI experience.Results: Children’s communication and general functioning with a CI received the most positive parental ratings. Among a number of confirmed statistically significant (p < 0.05) associations between HRQoL outcomes and demographic variables, pre-lingual onset of deafness was linked to better HRQoL in terms of general functioning and well-being. While shorter duration of deafness and unilateral implantation were associated with higher parental ratings for self-reliance and well-being respectively, longer duration of CI use was linked to improved HRQoL outcomes in terms of general functioning.Conclusion: Parents assigned positive ratings to their child’s HRQoL. This exploration of children’s HRQoL related to their CIs contributes to evidence-based paediatric CI services that promote optimal psychosocial outcomes.