Duration of cochlear implant use in children with prelingual single-sided deafness is a predictor of word perception in the CI ear.

As part of a longitudinal study regarding the benefit of early cochlear implantation for children with single-sided deafness, the current work explored the children's daily device use, potential barriers to full-time device use, and the children's ability to understand speech with the cochlear implant (CI). Data were collected from 20 children with prelingual SSD who received a CI before the age of 2.5 years, from the initial activation of the sound processor until the children were 4.8 to 11.0 years old. Daily device use was extracted from the CI's data logging, while word perception in quiet was assessed using direct audio input to the children's sound processor. The children's caregivers completed a questionnaire about habits, motivations, and barriers to device use. The children with SSD and a CI used their device on average 8.3 h per day, corresponding to 63 % of their time spent awake. All children except one could understand speech through the CI, with an average score of 59 % on a closed-set test and 73 % on an open-set test. More device use was associated with higher speech perception scores. Parents were happy with their decision to pursue a CI for their child. Certain habits, like taking off the sound processor during illness, were associated with lower device use. Providing timely counselling to the children's parents, focused on SSD-specific challenges, may be helpful to improve daily device use in these children.

The relation between cochlear implant programming levels and speech perception performance in post-lingually deafened adults: a data-driven approach.

PURPOSE: Programming a cochlear implant (fitting) is an essential part of a user's post-implantation journey, defining how sound will be translated into electrical stimulation and aiming to provide optimal speech perception outcomes. Currently, there are no established, evidence-based guidelines for fitting cochlear implant users, leading to a high degree of variability in fitting practices, users' parameters, and probably outcomes. In this study a data-driven approach is used to retrospectively investigate the relation between cochlear implant fitting parameters and speech perception outcomes in post-lingually deafened adults. METHODS: 298 data points corresponding to fitting parameters and speech audiometry test results for the same number of adult, post-lingually deafened, experienced CI users were analyzed. Correlation analysis was performed, after which parameters from the top-scoring and bottom-scoring tertiles were compared via the Mann-Whitney-Wilcoxon u test. RESULTS: Weak correlations between dynamic range and speech audiometry outcomes were identified, having p values lower than (albeit close to) 0.05. A significant (p < 0.05) difference in electrical dynamic range (the difference between the minimum and maximum amount of current which may be delivered by each electrode) was found, with top-scoring subjects having on average a wider dynamic range. CONCLUSION: The association between dynamic range and speech perception outcomes shown in this retrospective study highlights the need for deeper investigation into evidence-driven fitting. It might be a first step in the direction of evidence-based fitting, minimizing variability in outcomes for cochlear implant users and helping mitigate the issue of unexplained low performance.

Phoneme Training for Adult Cochlear Implant Users: A Review of the Literature and Study Protocol.

PURPOSE: This study describes a protocol for a novel individualized phoneme training program for adult cochlear implant (CI) users, based on individual phoneme confusion errors. The protocol is underpinned by a literature review on phoneme training and a focus group with adult CI users. METHOD: After a literature search, five studies were included for review and evaluation of quality and level of evidence. A focus group with experienced adult CI users (n = 7) was then conducted to gain insights into their experiences of auditory training post-implantation and recommendations for future training programs. The knowledge gained from the literature review and focus group was used as the foundation for a novel, individualized phoneme training program for adult CI users, for which the protocol is described in this study. RESULTS: A review of the literature shows that phoneme training in adult CI users has variable outcomes for on-task and off-task measures. Overall, the concept of individualized training relates to adaptive difficulty within training tasks and not to tailoring training content to participants' individual needs, as indicated by clinical outcomes. The focus group revealed that participants want to be able to track their training progress, have training content tailored to their individual needs, and expressed a preference for shorter training sessions. CONCLUSIONS: Using learnings from a literature review and focus group, this study describes a protocol for a novel, individualized phoneme training program for adult CI users. Study findings from this phoneme training program will be disseminated when available. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.24392863.

Variability in clinicians' prediction accuracy for outcomes of adult cochlear implant users.

OBJECTIVE: The variability in outcomes among adult cochlear implant (CI) users poses challenges for clinicians in accurately predicting the benefits of the implant for individual candidates. This study aimed to investigate the accuracy and confidence of clinicians in predicting speech perception outcomes for adult CI users one-year post-implantation. DESIGN: Participants were presented with comprehensive information on pre-implantation, one-month post-implantation, and six-month post-implantation data for 10 case studies. The cases encompassed a range of one-year post-implantation phoneme scores, from low performers (27%) to high performers (92%). Participants were tasked with predicting the speech perception outcomes for these cases one year after implantation. STUDY SAMPLE: Forty-one clinicians completed the full outcome prediction survey. RESULTS: Our findings revealed a significant over-prediction of low performance by clinicians. Interestingly, clinicians tended to predict average performance (73-76% phoneme score) even when provided with information suggesting lower-than-average performance. Most clinicians expressed confidence in their predictions, irrespective of their accuracy. CONCLUSIONS: Identifying signs of low performance, particularly in the early post-implantation period, can enable clinicians to implement early interventions. Further research into accurate outcome prediction is essential for managing expectations, providing counselling, increasing CI adoption, and optimising clinical care for both high and low performers.

Early cochlear implantation supports narrative skills of children with prelingual single-sided deafness.

Prelingual single-sided deafness (SSD) not only affects children's hearing skills, but can also lead to speech-language delays and academic underachievement. Early cochlear implantation leads to improved spatial hearing, but the impact on language development is less studied. In our longitudinal study, we assessed the language skills of young children with SSD and a cochlear implant (CI). In particular, we investigated their narrative skills in comparison to two control groups: children with SSD without a CI, and children with bilateral normal hearing. We found that children with SSD and a CI performed in line with their normal-hearing peers with regard to narrative and verbal short-term memory skills. Children with SSD without a CI had worse narrative (group difference = - 0.67, p = 0.02) and verbal short-term memory (group difference = - 0.68, p = 0.03) scores than the implanted group. Verbal short-term memory scores and grammar scores each correlated positively with narrative scores across all groups. Early grammar scores (at 2-3 years of age) could partially predict later narrative scores (at 4-6 years of age). These results show that young children with prelingual SSD can benefit from early cochlear implantation to achieve age-appropriate language skills. They support the provision of a CI to children with prelingual SSD.

Exploring neurocognitive factors and brain activation in adult cochlear implant recipients associated with speech perception outcomes-A scoping review.

Background: Cochlear implants (CIs) are considered an effective treatment for severe-to-profound sensorineural hearing loss. However, speech perception outcomes are highly variable among adult CI recipients. Top-down neurocognitive factors have been hypothesized to contribute to this variation that is currently only partly explained by biological and audiological factors. Studies investigating this, use varying methods and observe varying outcomes, and their relevance has yet to be evaluated in a review. Gathering and structuring this evidence in this scoping review provides a clear overview of where this research line currently stands, with the aim of guiding future research. Objective: To understand to which extent different neurocognitive factors influence speech perception in adult CI users with a postlingual onset of hearing loss, by systematically reviewing the literature. Methods: A systematic scoping review was performed according to the PRISMA guidelines. Studies investigating the influence of one or more neurocognitive factors on speech perception post-implantation were included. Word and sentence perception in quiet and noise were included as speech perception outcome metrics and six key neurocognitive domains, as defined by the DSM-5, were covered during the literature search (Protocol in open science registries: 10.17605/OSF.IO/Z3G7W of searches in June 2020, April 2022). Results: From 5,668 retrieved articles, 54 articles were included and grouped into three categories using different measures to relate to speech perception outcomes: (1) Nineteen studies investigating brain activation, (2) Thirty-one investigating performance on cognitive tests, and (3) Eighteen investigating linguistic skills. Conclusion: The use of cognitive functions, recruiting the frontal cortex, the use of visual cues, recruiting the occipital cortex, and the temporal cortex still available for language processing, are beneficial for adult CI users. Cognitive assessments indicate that performance on non-verbal intelligence tasks positively correlated with speech perception outcomes. Performance on auditory or visual working memory, learning, memory and vocabulary tasks were unrelated to speech perception outcomes and performance on the Stroop task not to word perception in quiet. However, there are still many uncertainties regarding the explanation of inconsistent results between papers and more comprehensive studies are needed e.g., including different assessment times, or combining neuroimaging and behavioral measures. Systematic review registration: https://doi.org/10.17605/OSF.IO/Z3G7W.

Longitudinal auditory data of children with prelingual single-sided deafness managed with early cochlear implantation.

Individuals with single-sided deafness (SSD) have no access to binaural hearing, which limits their ability to localize sounds and understand speech in noisy environments. In addition, children with prelingual SSD are at risk for neurocognitive and academic difficulties. Early cochlear implantation may lead to improved hearing outcomes by restoring bilateral hearing. However, its longitudinal impact on the development of children with SSD remains unclear. In the current study, a group of young children with prelingual SSD received a cochlear implant at an early age. From the age of four, the children's spatial hearing skills could be assessed using a spatial speech perception in noise test and a sound localization test. The results are compared to those of two control groups: children with SSD without a cochlear implant and children with bilateral normal hearing. Overall, the implanted group exhibited improved speech perception in noise abilities and better sound localization skills, compared to their non-implanted peers. On average, the children wore their device approximately nine hours a day. Given the large contribution of maturation to the development of spatial hearing skills, further follow-up is important to understand the long-term benefit of a cochlear implant for children with prelingual SSD.

Assessment of Receptive and Expressive Language Skills Among Young Children With Prelingual Single-Sided Deafness Managed With Early Cochlear Implantation.

Importance: Pediatric single-sided deafness (SSD) can seriously affect development, causing impaired spatial hearing skills, speech-language delays, and academic underachievement. Early cochlear implantation likely improves hearing-related outcomes, but its association with language development remains unclear. Objective: To investigate whether early cochlear implantation is associated with language outcomes for children with prelingual SSD. Design, Setting, and Participants: The Cochlear Implant for Children and One Deaf Ear study was initiated in 2015 and recruited participants at 4 academic hospitals in Flanders, Belgium, through 2019. This cohort study included 3 groups of children aged 2 to 5 years: children with SSD and a cochlear implant, children with SSD without a cochlear implant, and a control group with normal hearing. Language and hearing skills were assessed 1 to 2 times per year until the age of 10 years. Study completion rates were high (82%). Data analysis was performed from October to December 2020. Exposure: Unilateral cochlear implant. Main Outcomes and Measures: Longitudinal vocabulary, grammar, and receptive language scores. The implanted group was hypothesized to outperform the nonimplanted group on all language tests. Results: During the recruitment period, 47 children with prelingual SSD without additional disabilities were identified at the participating hospitals. Fifteen of the 34 children with an intact auditory nerve received a cochlear implant (44%, convenience sample). Sixteen of the remaining children were enrolled in the SSD control group (50%). Data from 61 children (mean [SD] age at the time of enrollment, 2.08 [1.34] years; 26 girls [42%]) were included in the analysis: 15 children with SSD and a cochlear implant, 16 children with SSD without a cochlear implant, and 30 children with normal hearing. Children with SSD and a cochlear implant performed in line with their peers with normal hearing with regard to grammar. In contrast, children with SSD without a cochlear implant had worse grammar scores than the group with implants (-0.76; 95% CI, -0.31 to -1.21; P = .004) and the group with normal hearing (-0.53; 95% CI, -0.91 to -0.15; P = .02). The 3 groups had similar vocabulary and receptive language abilities. Conclusions and Relevance: These findings suggest that early cochlear implantation is associated with normal grammar development in young children with prelingual SSD. Although further follow-up will reveal the long-term outcomes of the cochlear implant for other skills, the current results will help clinicians and policy makers identify the best treatment option for these children.

Empowering Senior Cochlear Implant Users at Home via a Tablet Computer Application.

PURPOSE: The introduction of connectivity technologies in hearing implants allows new ways to support cochlear implant (CI) users remotely. Some functionalities and services that are traditionally only available in an in-clinic care model can now also be accessed at home. This study explores the feasibility of a prototype of a tablet computer application (MyHearingApp [MHA]) in a group of senior experienced CI users at home, evaluating usability and user motivation. METHOD: Based on user feedback, a tablet computer application (MHA) for the Cochlear Nucleus 6 CP910 sound processor was designed implementing six different functionalities: (a) My Hearing Tests, (b) My Environment, (c) My Hearing Journey, (d) Tip of the Day, (e) Recipient Portal, and (f) Program Use and Events. The clinical evaluation design was a prospective study of the MHA in 16 senior experienced CI users. During 4 weeks, participants could freely explore the functionalities. At the end, the usability and their motivation for uptake and adherence were measured using a baseline and follow-up questionnaire. RESULTS: Based on the System Usability Score (as part of the follow-up questionnaire), a good level of usability was indicated (M = 75.6, range: 62.5-92.5, SD = 8.6). The ability to perform hearing tests at home is ranked as the most relevant functionality within the MHA. According to the Intrinsic Motivation Inventory (Deci, Eghrari, Patrick, & Leone, 1994) questionnaire (as part of the follow-up questionnaire), participants reported high levels of interest and enjoyment, found themselves competent, and did not experience pressure while working with the app. CONCLUSIONS: This study evaluated a tablet computer application (MHA) for experienced senior CI users by means of a prospective design, which provided novel insights into delivering CI care into the home of the CI user. The user feedback from this small-scale study suggests that the participants are open to take more responsibility for and to become a more active actor in their own hearing care, if only this is facilitated with the right tools. This may foster the evolution from a clinic-led to a more patient-centered care model, where CI users feel more empowered in the self-management of their hearing implant device.

Conversion of adult Nucleus® 5 cochlear implant users to the Nucleus® 6 system.

OBJECTIVES: Cochlear's new sound processor system (Nucleus(®) 6) features a new noise reduction algorithm called SNR-NR (signal-to-noise ratio), and an environmental classifier called SCAN, which activates the appropriate sound coding algorithms for a given listening environment. In addition, the sound processors (CP910 and CP920) have a data logging feature with data visually summarized using clinical programing software and come with two remote controls, CR210 and CR230. The objective of this clinical study was to conduct a field acceptance study comparing the user experience with the Nucleus(®) 6 to the Nucleus(®) 5 system and to evaluate the benefits of Nucleus(®) 6 in an adult population currently equipped with the previous generation Nucleus(®) 5 sound processor. Our primary objective was to compare speech recognition in speech-weighted noise using Nucleus(®) 6 with SCAN (activating SNR-NR) with the default Nucleus(®) 5 'Noise' Program. Secondary objectives included comparisons of speech recognition in quiet, subjective performance feedback via questionnaires and diaries, and recipient preference for device and program type. METHODS: A prospective controlled trial was conducted with 30 adult Nucleus CI recipients using the Nucleus(®) 5 sound processor (condition A). The Nucleus(®) 6 sound processor (condition B) was evaluated in a within-subject ABBA design, with repeated speech in noise (S0N0, LIST sentence test), and speech in quiet testing (S0, NVA words). The remote controls were randomly given during the two B intervals. In addition, recipients had to complete questionnaires and diaries on the use of their current as well as new sound processors and remotes. RESULTS: The group mean speech reception threshold in noise (SRT50) with Nucleus(®) 6 SCAN was significantly better (1.2 dB SNR) than with the Nucleus(®) 5 'Noise' Program. Mean speech recognition scores in quiet were not significantly different between the processors. Subjective performance feedback (APHAB) did not show a significant difference between Nucleus(®) 6 and Nucleus(®) 5 with high satisfaction scores being reported for both sound processors. Recipients preferred the SCAN program in noise and reported a clear overall preference for the Nucleus(®) 6 system. Clinicians were satisfied with the conversion process from Nucleus(®) 5 to Nucleus(®) 6. DISCUSSION AND CONCLUSION: SNR-NR provides a significant benefit in noise. Recipients were easily converted from Nucleus(®) 5 to Nucleus(®) 6 requiring little or no sound quality adjustment period. The Nucleus(®) 6 SCAN program was well accepted by the majority of recipients for use during their daily life.

Cochlear implants in children deafened by congenital cytomegalovirus and matched Connexin 26 peers.

OBJECTIVE: To compare the long-term speech perception and production outcomes after cochlear implantation (CI) in children deafened by congenital cytomegalovirus (cCMV) with a matched group of Cx26-CI children by controlling for chronological age and magnetic resonance imaging (MRI) findings. METHODS: Retrospective review of 12 cCMV-CI children and matched Cx26-CI children for speech perception and speech production outcomes. RESULTS: Two trends were seen in our data. First, cCMV-CI children with normal MRI scans perform equally or even slightly better on speech perception tests compared to their Cx26-CI peers during the first three years. The majority of cCMV-CI children with normal MRI scans (5 out of 7), suffered from a delayed-onset SNHL. Their mean age at first implantation (2y9m, range 15-82m) was higher compared to their matched Cx26 peers (9m, range 7-12m). Before being implanted, the majority of these delayed-onset hearing impaired children had benefited from a certain period of normal hearing (with or without amplification of a hearing aid). Possibly, this input might have led to an advantage the first three years after CI. Second, results between cCMV-CI children with and cCMV-CI children without MRI abnormalities and their matched Cx26-CI counterparts tentatively suggest that, over a 5-yr follow-up period, cCMV-CI children with abnormalities on MRI scans catch up for speech perception, but lag behind for speech production. CONCLUSION: cCMV-CI children with normal MRI scans perform equally or even slightly better on speech perception tests compared to their Cx26-CI peers during the first three years, whereas results between cCMV-CI children with and cCMV-CI children without MRI abnormalities and their matched Cx26-CI counterparts tentatively suggest that, over a 5-yr follow-up period, cCMV-CI children with abnormal MRI scans catch up for speech perception, but lag behind for speech production. In future, the inclusion of MRI results may assist in improved counseling of parents with cCMV deafened children seeking CI.

Results of a multicenter clinical study evaluating a new Smart algorithm to measure neural response imaging.

OBJECTIVE: To evaluate the smart algorithm in speed and reliability of threshold estimation compared with the algorithm available in the standard fitting software and to evaluate the possibility of using programs based on the smart algorithm instead of programs derived from behavioral measures. PATIENTS: Twenty subjects unilaterally implanted with a CII Bionic Ear or HiRes90K device. INTERVENTIONS: Neural response imaging thresholds (tNRI) were measured using both the smart approach within the Research Studies Platform for Objective Measures and the SoundWave fitting software. Measurements were performed intraoperatively, at first fitting, and after 3 months of implant use. Each subject received a standard behavioral program and a SmartNRI program. Speech perception tests were conducted at 3 months, and subjective preferences were documented. MAIN OUTCOME MEASURES: Smart tNRI and SoundWave tNRI at each session; speech test results and subject preferences at the 3-month session. RESULTS: High correlations were found between smart tNRI and SoundWave tNRI. The time required to obtain NRI thresholds with the smart algorithm was a quarter of the time needed with SoundWave. Although most tested subjects preferred their behavioral programs, there were no significant differences in performance between SmartNRI and behavioral programs. CONCLUSION: Neural response imaging thresholds were obtained more rapidly with the smart algorithm than with SoundWave. Because no differences were observed between SmartNRI and behavioral programs, SmartNRI programs may be a useful alternative to behavioral programs in difficult to fit cases, where user feedback is sometimes difficult to obtain.

Effect of pediatric bilateral cochlear implantation on language development.

OBJECTIVE: To examine spoken language outcomes in children undergoing bilateral cochlear implantation compared with matched peers undergoing unilateral implantation. DESIGN: Case-control, frequency-matched, retrospective cross-sectional multicenter study. SETTING: Two Belgian and 3 Dutch cochlear implantation centers. PARTICIPANTS: Twenty-five children with 1 cochlear implant matched with 25 children with 2 cochlear implants selected from a retrospective sample of 288 children who underwent cochlear implantation before 5 years of age. INTERVENTION: Cochlear implantation. MAIN OUTCOME MEASURES: Performance on measures of spoken language comprehension and expression (Reynell Developmental Language Scales and Schlichting Expressive Language Test). RESULTS: On the receptive language tests (mean difference [95% CI], 9.4 [0.3-18.6]) and expressive language tests (15.7 [5.9-25.4] and 9.7 [1.5-17.9]), children undergoing bilateral implantation performed significantly better than those undergoing unilateral implantation. Because the 2 groups were matched with great care on 10 auditory, child, and environmental factors, the difference in performance can be mainly attributed to the bilateral implantation. A shorter interval between both implantations was related to higher standard scores. Children undergoing 2 simultaneous cochlear implantations performed better on the expressive Word Development Test than did children undergoing 2 sequential cochlear implantations. CONCLUSIONS: The use of bilateral cochlear implants is associated with better spoken language learning. The interval between the first and second implantation correlates negatively with language scores. On expressive language development, we find an advantage for simultaneous compared with sequential implantation.

Characteristics and determinants of music appreciation in adult CI users.

The main objective of this study was to assess the associations between self-reported listening habits and perception of music and speech perception outcomes in quiet and noise for both unilateral cochlear implant (CI) users and bimodal (CI in one ear, hearing aid in contra-lateral ear) users. Information concerning music appreciation was gathered by means of a newly developed questionnaire. Moreover, audiological data (pure-tone audiometry, speech tests in noise and quiet) were gathered and the relationship between speech perception and music appreciation is studied. Bimodal users enjoy listening to music more in comparison with unilateral CI users. Also, music training within rehabilitation is still uncommon, while CI recipients believe that music training might be helpful to maximize their potential with current CI technology. Music training should not be exclusively reserved for the good speech performers. Therefore, a music training program (MTP) that consists of different difficulty levels should be developed. Hopefully, early implementation of MTP in rehabilitation programs can enable adult CI users to enjoy and appreciate music and to maximize their potential with commercially available technology. Furthermore, because bimodal users consider the bimodal stimulation to be the most enjoyable way to listen to music, CI users with residual hearing in the contra-lateral ear should be encouraged to continue wearing their hearing aid in that ear.

Clinical usefulness of the rotatory, caloric, and vestibular evoked myogenic potential test in unilateral peripheral vestibular pathologies.

OBJECTIVE: The aim of this study was to investigate the diagnostic capacity of three different rotatory tests, and to investigate the clinical effectiveness of the caloric, rotatory, and vestibular evoked myogenic potential (VEMP) test. DESIGN AND STUDY SAMPLE: Several rotatory tests--sinusoidal harmonic acceleration test (SHAT), pseudorandom rotation test (PRRT), velocity step test (VST)--and a caloric and a VEMP test, were given to 77 patients (mean age 52 years) with a unilateral peripheral vestibular pathology, and 80 control subjects (mean age 48 years). RESULTS: For the rotatory test, the highest diagnostic capacity was obtained with the 0.01 Hz SHAT frequency, followed by 0.1 and 0.05 Hz. A higher diagnostic accuracy was reached for the caloric and VEMP test. The caloric test demonstrated high sensitivity and specificity values, but the 0.01 Hz SHAT rotation appeared more sensitive, and the VEMP more specific, than the caloric test. CONCLUSION: A selection of the 0.01, 0.05, and 0.1 Hz SHAT rotations is suggested as the most ideal rotatory test protocol, and a combination of rotatory, caloric, and VEMP testing will result in a more complete examination of our vestibular system.

Speech recognition in noise with active and passive hearing protectors: a comparative study.

The perceived negative influence of standard hearing protectors on communication is a common argument for not wearing them. Thus, "augmented" protectors have been developed to improve speech intelligibility. Nevertheless, their actual benefit remains a point of concern. In this paper, speech perception with active earplugs is compared to standard passive custom-made earplugs. The two types of active protectors included amplify the incoming sound with a fixed level or to a user selected fraction of the maximum safe level. For the latter type, minimal and maximal amplification are selected. To compare speech intelligibility, 20 different speech-in-noise fragments are presented to 60 normal-hearing subjects and speech recognition is scored. The background noise is selected from realistic industrial noise samples with different intensity, frequency, and temporal characteristics. Statistical analyses suggest that the protectors' performance strongly depends on the noise condition. The active protectors with minimal amplification outclass the others for the most difficult and the easiest situations, but they also limit binaural listening. In other conditions, the passive protectors clearly surpass their active counterparts. Subsequently, test fragments are analyzed acoustically to clarify the results. This provides useful information for developing prototypes, but also indicates that tests with human subjects remain essential.

Short-term auditory effects of listening to an MP3 player.

OBJECTIVES: To determine the output levels of a commercially available MPEG layer-3 (MP3) player and to evaluate changes in hearing after 1 hour of listening to the MP3 player. DESIGN: First, A-weighted sound pressure levels (measured in decibels [dBA]) for 1 hour of pop-rock music on an MP3 player were measured on a head and torso simulator. Second, after participants listened to 1 hour of pop-rock music using an MP3 player, changes in hearing were evaluated with pure-tone audiometry, transient-evoked otoacoustic emissions, and distortion product otoacoustic emissions. PARTICIPANTS: Twenty-one participants were exposed to pop-rock music in 6 different sessions using 2 types of headphones at multiple preset gain settings of the MP3 player. MAIN OUTCOME MEASURES: Output levels of an MP3 player and temporary threshold and emission shifts after 1 hour of listening. RESULTS: The output levels at the full gain setting were 97.36 dBA and 102.56 dBA for the supra-aural headphones and stock earbuds, respectively. In the noise exposure group, significant changes in hearing thresholds and transient-evoked otoacoustic emission amplitudes were found between preexposure and postexposure measurements. However, this pattern was not seen for distortion product otoacoustic emission amplitudes. Significant differences in the incidence of significant threshold or emission shifts were observed between almost every session of the noise exposure group compared with the control group. CONCLUSIONS: Temporary changes in hearing sensitivity measured by audiometry and otoacoustic emissions indicate the potential harmful effects of listening to an MP3 player. Further research is needed to evaluate the long-term risk of cumulative noise exposure on the auditory system of adolescents and adults.

Determination and evaluation of clinically efficient stopping criteria for the multiple auditory steady-state response technique.

OBJECTIVE: The present study aimed at establishing clinically efficient stopping criteria for a multiple 80-Hz auditory steady-state response (ASSR) system. METHODS: In Experiment 1, data of 31 normal-hearing subjects were analyzed off-line to propose stopping rules. Consequently, ASSR recordings will be stopped when (1) all 8 responses reach significance and significance can be maintained for 8 consecutive sweeps; or (2) the mean noise levels were 4nV (if p-values were between 0.05 and 0.1, measurements were extended once by 8 sweeps); or (3) a maximum amount of 48 sweeps was attained; whichever occurred first. In Experiment 2, these stopping criteria were applied on 10 normal hearing and 10 hearing-impaired adults to assess the efficiency. RESULTS: The application of these stopping rules resulted in ASSR threshold values that were comparable to other ASSR research. Furthermore, preliminary analysis of the response and noise amplitudes demonstrated slightly higher values for hearing impaired than normal-hearing subjects. CONCLUSIONS: The proposed stopping rules can be used in adults to determine accurate ASSR thresholds within a time-frame of about 1h. SIGNIFICANCE: The use of these a priori stopping criteria might assist the clinician in their decision to terminate ASSR recordings.

Transient-evoked and distortion product otoacoustic emissions: A short-term test-retest reliability study.

Knowledge regarding the variability of transient-evoked otoacoustic emissions (TEOAEs) and distortion product otoacoustic emissions (DPOAEs) is essential in clinical settings and improves their utility in monitoring hearing status over time. In the current study, TEOAEs and DPOAEs were measured with commercially available OAE-equipment in 56 normally-hearing ears during three sessions. Reliability was analysed for the retest measurement without probe-refitting, the immediate retest measurement with probe-refitting, and retest measurements after one hour and one week. The highest reliability was obtained in the retest measurement without probe-refitting, and decreased with increasing time-interval between measurements. For TEOAEs, the lowest reliability was seen at half-octave frequency bands 1.0 and 1.4 kHz; whereas for DPOAEs half-octave frequency band 8.0 kHz had also poor reliability. Higher primary tone level combination for DPOAEs yielded to a better reliability of DPOAE amplitudes. External environmental noise seemed to be the dominating noise source in normal-hearing subjects, decreasing the reliability of emission amplitudes especially in the low-frequency region.