The word-with-noise test: test-retest reliability in normal-hearing adults. / Teste de palavras no ruído: confiabilidade no teste-reteste em adultos normo-ouvintes.

PURPOSE: To investigate the reliability of the Word-with-Noise Test in a group of normal-hearing adults. METHODS: Forty-five normal-hearing adult subjects participated in the research. The interval between the first and second assessment was 14 to 28 days, performed during the same time of the day and by the same evaluator. The comparison analysis between the test and the retest was performed considering the general result of the ears, totaling 90 ears evaluated. The inferential analysis included the comparison of the situations in the first and second assessment using the Wilcoxon Test, calculation, and interpretation of the Intraclass Correlation Index. RESULTS: There was a statistically significant difference between the test and retest performances. The intraclass correlation coefficients obtained were indicative of good reliability (r=0.759; p<0.001) for the monosyllabic stimulus and moderate reliability (r=0.631; p<0.001) for the disyllabic stimulus. CONCLUSION: The Word-with-Noise Test demonstrated satisfactory reliability for both the monosyllabic and disyllabic stimuli.

OBJETIVO: Investigar a confiabilidade do Teste de Palavras no Ruído em um grupo de adultos normo-ouvintes. MÉTODO: Participaram da pesquisa 45 sujeitos adultos normo-ouvintes. O intervalo entre a primeira e a segunda avaliação foi de 14 a 28 dias, realizadas no mesmo turno do dia e pelo mesmo avaliador. A análise de comparação entre teste e reteste foi realizada considerando o resultado geral das orelhas, totalizando 90 orelhas avaliadas. A análise inferencial incluiu a comparação das situações na primeira e segunda avaliação por meio do Teste de Wilcoxon, cálculo e interpretação do Índice de Correlação Intraclasse. RESULTADOS: Houve diferença estatisticamente significante entre os desempenhos no teste e reteste. Os coeficientes de correlação intraclasse obtidos foram indicativos de boa confiabilidade (r=0,759; p<0,001) para o estímulo monossilábico e de moderada confiabilidade (r=0,631; p<0,001) para o dissilábico. CONCLUSÃO: O Teste de Palavras no Ruído demonstrou satisfatória confiabilidade tanto para o estímulo monossilábico, quanto para o dissilábico.

Availability of resources for paediatric hearing care in a South African province.

BACKGROUND:  Unavailability of healthcare resources can lead to poor patient outcomes. The latter is true for infants with hearing loss and require early hearing detection and intervention (EHDI). AIM:  To determine the availability and distribution of resources for EHDI in state hospitals in the Eastern Cape (EC) province, South Africa. SETTING:  Sixteen state hospitals (nine district, four regional and three tertiary hospitals). METHODS:  Descriptive cross-sectional survey completed between July 2022 and October 2022. RESULTS:  Thirteen hospitals had audiologists (n = 4) or speech therapists and audiologists (n = 9). Specific to equipment, 10 hospitals had a screening otoacoustic emissions or automated auditory brainstem response, 8 hospitals had diagnostic middle ear analysers and only 3 hospitals had diagnostic auditory brainstem response and/or auditory steady state response. Twelve hospitals did not have visual response audiometry (VRA) and 94% had no hearing aid verification systems. Budget allocations were uneven, with only 10 hospitals, i.e., 4 districts, all regional and 2 tertiary hospitals being allocated varying amounts. Subsequently, only 50% provided newborn hearing screening, 56% provided diagnostic evaluations and 14 hospitals fitted hearing aids. CONCLUSION:  Results revealed a limited and uneven distribution of resources, which negatively impacted the provision of EHDI. Even distribution of healthcare resources and further research aimed at strengthening hearing health services is recommended as these could potentially improve equitable access to EHDI and the overall quality of healthcare provided.Contribution: This study highlights the need for even distribution of resources and strengthening of health systems, especially in the dawn of the National Health Insurance.

A call for linguistic and culturally congruent family-centred early hearing detection and intervention programmes in South Africa.

Early Hearing Detection and Intervention (EHDI) programmes are recognised as the standard of care for newborns and infants presenting with hearing impairment, globally. However, widespread implementation of these programmes is far from being realised and faces numerous challenges within the South African context. The United Nations' sustainable development goal 3.8 and South Africa's national development plan seek to achieve equitable access to healthcare service, including EHDI. However, healthcare access is a complex concept which encompasses the dimensions: availability, affordability, acceptability and accommodation in healthcare. South Africa has made great progress towards universal implementation of EHDI programmes. Despite this progress, availability and affordability of these programmes are limited and their acceptability has received limited research focus in this context. Furthermore, accommodation of caregivers, as co-drivers of EHDI programmes and ensuring that EHDI programmes are linguistically and culturally congruent have also been overlooked within the South African context.Contribution: Increased robust efforts in improving access through availability and affordability of EHDI programmes are warranted in South Africa. However, improving access to these programmes through availability and affordability initiatives alone will not result in a pragmatic improvement in their accessibility. Acceptability of these programmes and accommodations such as involving caregivers and family members of children with hearing impairment as equal partners in EHDI programmes and being cognisant of their linguistic and cultural needs must be considered.

Investigation on the contribution of swim bladder to hearing in crucian carp (Carassius carassius).

The swim bladder in some teleost fish functions to transfer the sound energy of acoustic stimuli to the inner ears. This study uses the auditory evoked potential tests, micro-computed tomography scanning, reconstruction, and numerical modeling to assess the contribution of the swim bladder to hearing in crucian carp (Carassius carassius). The auditory evoked potential results show that, at the tested frequency range, the audiogram of fish with an intact swim bladder linearly increases, ranging from 100 to 600 Hz. Over this frequency, the sound pressure thresholds have a local lowest value at 800 Hz. The mean auditory threshold of fish with an intact swim bladder is lower than that of fish with a deflated swim bladder by 0.8-20.7 dB. Furthermore, numerical simulations show that the received pressure of the intact swim bladders occurs at a mean peak frequency of 826 ± 13.6 Hz, and no peak response is found in the deflated swim bladders. The increased sensitivity of reception in sound pressure and acceleration are 34.4 dB re 1 µPa and 40.3 dB re 1 m·s-2 at the natural frequency of swim bladder, respectively. Both electrophysiological measurement and numerical simulation results show that the swim bladder can potentially extend hearing bandwidth and further enhance auditory sensitivity in C. carassius.

Automated Speech Audiometry: Can It Work Using Open-Source Pre-Trained Kaldi-NL Automatic Speech Recognition?

A practical speech audiometry tool is the digits-in-noise (DIN) test for hearing screening of populations of varying ages and hearing status. The test is usually conducted by a human supervisor (e.g., clinician), who scores the responses spoken by the listener, or online, where software scores the responses entered by the listener. The test has 24-digit triplets presented in an adaptive staircase procedure, resulting in a speech reception threshold (SRT). We propose an alternative automated DIN test setup that can evaluate spoken responses whilst conducted without a human supervisor, using the open-source automatic speech recognition toolkit, Kaldi-NL. Thirty self-reported normal-hearing Dutch adults (19-64 years) completed one DIN + Kaldi-NL test. Their spoken responses were recorded and used for evaluating the transcript of decoded responses by Kaldi-NL. Study 1 evaluated the Kaldi-NL performance through its word error rate (WER), percentage of summed decoding errors regarding only digits found in the transcript compared to the total number of digits present in the spoken responses. Average WER across participants was 5.0% (range 0-48%, SD = 8.8%), with average decoding errors in three triplets per participant. Study 2 analyzed the effect that triplets with decoding errors from Kaldi-NL had on the DIN test output (SRT), using bootstrapping simulations. Previous research indicated 0.70 dB as the typical within-subject SRT variability for normal-hearing adults. Study 2 showed that up to four triplets with decoding errors produce SRT variations within this range, suggesting that our proposed setup could be feasible for clinical applications.

Sensitivity of Methods for Diagnosing Noise-Induced Hearing Loss in Cases of Exposures Including Intense Low-Frequency Noise.

Exposure to intense low-frequency sounds, for example inside tanks and armoured vehicles, can lead to noise-induced hearing loss (NIHL) with a variable audiometric pattern, including low- and mid-frequency hearing loss. It is not known how well existing methods for diagnosing NIHL apply in such cases. Here, the audiograms of 68 military personnel (mostly veterans) who had been exposed to intense low-frequency noise (together with other types of noise) and who had low-frequency hearing loss (defined as a pure-tone average loss at 0.25, 0.5 and 1 kHz ≥20 dB) were used to assess the sensitivity of three diagnostic methods: the method of Coles, Lutman and Buffin, denoted CLB, which depends on the identification of a notch or bulge in the audiogram near 4 kHz, and two methods specifically intended for diagnosing NIHL sustained during military service, the rM-NIHL method, which depends on the identification of a notch or bulge in the audiogram near 4 kHz and/or a hearing loss at high frequencies greater than expected from age alone, and the MLP(18) method based on a multi-layer perceptron. The proportion of individuals receiving a positive diagnosis for either or both ears, which provides an approximate measure of sensitivity, was 0.40 for the CLB method, 0.79 for the rM-NIHL method and 1.0 for the MLP(18) method. It is concluded that the MLP(18) method is suitable for diagnosing NIHL sustained during military service whether or not the exposure includes intense low-frequency sounds.

Predictors of the Outcome at 2 Years in Neonates With Congenital Cytomegalovirus Infection.

BACKGROUND: Approximately 20% of neonates with congenital cytomegalovirus (cCMV) develop long-term sequelae. The ability to accurately predict long-term outcomes as early as the neonatal period would help to provide for appropriate parental counseling and treatment indications. With this study, we aimed to identify neonatal predictive markers of cCMV long-term outcomes. METHODS: As this study's subjects, we chose neonates diagnosed with cCMV in 13 hospitals throughout France recruited from 2013 to 2017 and evaluated for at least 2 years with thorough clinical, audiology, and imaging evaluations and psychomotor development tests. RESULTS: A total of 253 neonates were included, and 3 were later excluded because of the identification of a genetic disorder. A total of 227 were followed up for 2 years: 187/227 (82%) and 34/227 (15%) were infected after a maternal primary or nonprimary infection, respectively, 91/227 (40%) were symptomatic at birth, and 44/227 (19%) had cCMV sequelae. Maternal primary infection in the first trimester was the strongest prognosis factor (odds ratio = 38.34 [95% confidence interval, 5.02-293], P < .001). A predictive model of no risk of sequelae at 2 years of age according to normal hearing loss at birth, normal cerebral ultrasound, and normal platelet count had 98% specificity, 69% sensitivity, and 0.89 area under the curve (95% confidence interval, 0.83-0.96). CONCLUSIONS: In the studied population, children with normal hearing at birth, normal platelet count at birth, and a normal cranial ultrasound had no risk of neurologic sequelae and a low risk of delayed unilateral sensorineural hearing loss. The use of this model based on readily available neonatal markers should help clinicians establish a personalized care pathway for each cCMV neonate.

Otoacoustic emissions in African mole-rats.

African mole-rats display highly derived hearing that is characterized by low sensitivity and a narrow auditory range restricted to low frequencies < 10 kHz. Recently, it has been suggested that two species of these rodents do not exhibit distortion product otoacoustic emissions (DPOAE), which was interpreted as evidence for a lack of cochlear amplification. If true, this would make them unique among mammals. However, both theoretical considerations on the generation of DPOAE as well as previously published experimental evidence challenge this assumption. We measured DPOAE and stimulus-frequency otoacoustic emissions (SFOAE) in three species of African mole-rats (Ansell's mole-rat - Fukomys anselli; Mashona mole-rat - Fukomys darlingi; naked mole-rat - Heterocephalus glaber) and found unexceptional otoacoustic emission values. Measurements were complicated by the remarkably long, narrow and curved external ear canals of these animals, for which we provide a morphological description. Both DPOAE and SFOAE displayed the highest amplitudes near 1 kHz, which corresponds to the region of best hearing in all tested species, as well as to the frequency region of the low-frequency acoustic fovea previously described in Ansell's mole-rat. Thus, the cochlea in African mole-rats shares the ability to generate evoked otoacoustic emission with other mammals.

Lexical effects on talker discrimination in adult cochlear implant usersa).

The lexical and phonological content of an utterance impacts the processing of talker-specific details in normal-hearing (NH) listeners. Adult cochlear implant (CI) users demonstrate difficulties in talker discrimination, particularly for same-gender talker pairs, which may alter the reliance on lexical information in talker discrimination. The current study examined the effect of lexical content on talker discrimination in 24 adult CI users. In a remote AX talker discrimination task, word pairs-produced either by the same talker (ST) or different talkers with the same (DT-SG) or mixed genders (DT-MG)-were either lexically easy (high frequency, low neighborhood density) or lexically hard (low frequency, high neighborhood density). The task was completed in quiet and multi-talker babble (MTB). Results showed an effect of lexical difficulty on talker discrimination, for same-gender talker pairs in both quiet and MTB. CI users showed greater sensitivity in quiet as well as less response bias in both quiet and MTB for lexically easy words compared to lexically hard words. These results suggest that CI users make use of lexical content in same-gender talker discrimination, providing evidence for the contribution of linguistic information to the processing of degraded talker information by adult CI users.

Toward Sound Localization Testing in Virtual Reality to Aid in the Screening of Auditory Processing Disorders.

Sound localization testing is key for comprehensive hearing evaluations, particularly in cases of suspected auditory processing disorders. However, sound localization is not commonly assessed in clinical practice, likely due to the complexity and size of conventional measurement systems, which require semicircular loudspeaker arrays in large and acoustically treated rooms. To address this issue, we investigated the feasibility of testing sound localization in virtual reality (VR). Previous research has shown that virtualization can lead to an increase in localization blur. To measure these effects, we conducted a study with a group of normal-hearing adults, comparing sound localization performance in different augmented reality and VR scenarios. We started with a conventional loudspeaker-based measurement setup and gradually moved to a virtual audiovisual environment, testing sound localization in each scenario using a within-participant design. The loudspeaker-based experiment yielded results comparable to those reported in the literature, and the results of the virtual localization test provided new insights into localization performance in state-of-the-art VR environments. By comparing localization performance between the loudspeaker-based and virtual conditions, we were able to estimate the increase in localization blur induced by virtualization relative to a conventional test setup. Notably, our study provides the first proxy normative cutoff values for sound localization testing in VR. As an outlook, we discuss the potential of a VR-based sound localization test as a suitable, accessible, and portable alternative to conventional setups and how it could serve as a time- and resource-saving prescreening tool to avoid unnecessarily extensive and complex laboratory testing.

Towards universal access: A review of global efforts in ear and hearing care.

Hearing loss affects 1.6 billion people worldwide and disproportionately affects those in low- and middle-income countries. Despite being largely preventable or treatable, ear and hearing conditions result in significant and lifelong morbidity such as delayed language development, reduced educational attainment, and diminished social well-being. There is a need to augment prevention, early identification, treatment, and rehabilitation for these conditions. Expanded access to hearing screening, growth of the hearing health workforce, and innovations in ear and hearing care delivery systems are among the changes that are needed. To that end, the World Health Organization has prioritized ear and hearing care as a component of Universal Health Coverage, and recent publications have advanced the priority for ear and hearing care. Efforts are underway at the national levels around the world, as evidenced by countries like Zambia and Nigeria that have integrated ear and hearing care within national health strategies. While significant strides have been made in improving access, a critical need remains for additional research, advocacy, and intervention to ensure that no one is left behind in the goal to achieve universal access to ear and hearing care.

Reduced Channel Interaction Improves Timbre Recognition Under Vocoder Simulation of Cochlear Implant Processing.

OBJECTIVE: This study aimed to investigate the influence of the number of channels and channel interaction on timbre perception in cochlear implant (CI) processing. By utilizing vocoder simulations of CI processing, the effects of different numbers of channels and channel interaction were examined to assess their impact on timbre perception, an essential aspect of music and auditory performance. STUDY DESIGN, SETTING, AND PATIENTS: Fourteen CI recipients, with at least 1 year of CI device use, and two groups (N = 16 and N = 19) of normal hearing (NH) participants completed a timbre recognition (TR) task. NH participants were divided into two groups, with each group being tested on different aspects of the study. The first group underwent testing with varying numbers of channels (8, 12, 16, and 20) to determine an ideal number that closely reflected the TR performance of CI recipients. Subsequently, the second group of NH participants participated in the assessment of channel interaction, utilizing the identified ideal number of 20 channels, with three conditions: low interaction (54 dB/octave), medium interaction (24 dB/octave), and high interaction (12 dB/octave). Statistical analyses, including repeated-measures analysis of variance and pairwise comparisons, were conducted to examine the effects. RESULTS: The number of channels did not demonstrate a statistically significant effect on TR in NH participants ( p > 0.05). However, it was observed that the condition with 20 channels closely resembled the TR performance of CI recipients. In contrast, channel interaction exhibited a significant effect ( p < 0.001) on TR. Both the low interaction (54 dB/octave) and high interaction (12 dB/octave) conditions differed significantly from the actual CI recipients' performance. CONCLUSION: Timbre perception, a complex ability reliant on highly detailed spectral resolution, was not significantly influenced by the number of channels. However, channel interaction emerged as a significant factor affecting timbre perception. The differences observed under different channel interaction conditions suggest potential mechanisms, including reduced spectro-temporal resolution and degraded spectral cues. These findings highlight the importance of considering channel interaction and optimizing CI processing strategies to enhance music perception and overall auditory performance for CI recipients.

Over-the-Counter Hearing Aids Challenge the Core Values of Traditional Audiology.

PURPOSE: Regulatory changes in the United States introduced over-the-counter (OTC) hearing aids with the goal of increasing the accessibility and affordability of hearing health care. It is critical to understand the values inherent to hearing health care systems to evaluate their effectiveness in serving people with hearing difficulty. In this study, we evaluated the relative importance of values across service delivery models and the extent to which the introduction of OTC hearing aids represents a values shift relative to traditional audiology. METHOD: We performed a qualitative content analysis of two document categories: critique documents that motivated the creation of OTC hearing aids and regulatory documents that defined OTC hearing aids. Team members coded portions of text for the values they expressed. In total, 29,235 words were coded across 72 pages in four documents. Rank-order analyses were performed to determine the prioritization of values within each category of documents and subsequently compare values between OTC and traditional audiology documents analyzed in a previous study. RESULTS: Critique and regulatory documents both prioritized values related to reducing barriers to hearing aid access and use, but the lack of a significant correlation in the rank order of values in these documents was evidence of inconsistency between the motivation and implementation of OTC hearing aids. Differences in the rank order of values in the OTC documents compared to traditional audiology were consistent with a values shift. CONCLUSIONS: The introduction of OTC as a solution to low hearing aid use represents a values shift, challenging the values of traditional audiology. This research demonstrates a need to establish the values of hearing health care service delivery through a consensus of stakeholders, including individuals from diverse backgrounds underserved by the traditional model.

How I do it: hearing preservation in large vestibular schwannomas using vestibular nerve fiber preservation technique.

BACKGROUND: To improve hearing function after resection of large vestibular schwannomas, we describe a strategy of vestibular-nerve-fiber preservation. Anatomical considerations and stepwise dissection are described. METHOD: Steps include locating the vestibular nerve at the brainstem and identifying a dissection plane between nerve fibers and tumor capsule. Using this plane to mobilize and resect tumor reduced manipulation and maintained vascularity of underlying cochlear and facial nerves. CONCLUSION: Preservation of hearing function is feasible in large vestibular schwannomas with vestibular-nerve-fiber preservation. Reducing manipulation and ischemic injury of underlying cochlear and facial nerves thereby helped facilitate hearing preservation, even in large tumors.

Head and Eye Movements Reveal Compensatory Strategies for Acute Binaural Deficits During Sound Localization.

The present study aimed to define use of head and eye movements during sound localization in children and adults to: (1) assess effects of stationary versus moving sound and (2) define effects of binaural cues degraded through acute monaural ear plugging. Thirty-three youth (MAge = 12.9 years) and seventeen adults (MAge = 24.6 years) with typical hearing were recruited and asked to localize white noise anywhere within a horizontal arc from -60° (left) to +60° (right) azimuth in two conditions (typical binaural and right ear plugged). In each trial, sound was presented at an initial stationary position (L1) and then while moving at ∼4°/s until reaching a second position (L2). Sound moved in five conditions (±40°, ±20°, or 0°). Participants adjusted a laser pointer to indicate L1 and L2 positions. Unrestricted head and eye movements were collected with gyroscopic sensors on the head and eye-tracking glasses, respectively. Results confirmed that accurate sound localization of both stationary and moving sound is disrupted by acute monaural ear plugging. Eye movements preceded head movements for sound localization in normal binaural listening and head movements were larger than eye movements during monaural plugging. Head movements favored the unplugged left ear when stationary sounds were presented in the right hemifield and during sound motion in both hemifields regardless of the movement direction. Disrupted binaural cues have greater effects on localization of moving than stationary sound. Head movements reveal preferential use of the better-hearing ear and relatively stable eye positions likely reflect normal vestibular-ocular reflexes.

Associations Between Recreational Noise Exposure and Hearing Function in Adolescents and Young Adults: A Systematic Review.

PURPOSE: There is an increasing concern regarding hazardous recreational noise exposure among adolescents and young adults. Daily exposure to loud sound levels over a long period of time can increase the risk of noise-induced hearing loss. The full extent of the impact of recreational noise on hearing is not yet fully understood. The purpose of this review was to synthesize research that investigated hearing function in relation to recreational noise exposure in adolescents and young adults. METHOD: A systematic literature search of five databases covering the years 2000-2023 was performed. The articles included investigated audiological measurements of hearing function in relation to recreational noise exposure. RESULTS: Four hundred sixty records were identified, of which 20 met the inclusion criteria and were included in the results. This review showed that although some recreational noise activities can be potentially harmful, there is an unclear relationship between exposure and outcome. Some findings indicated hearing threshold shifts or reduced otoacoustic emission amplitudes after recreational noise exposure, but most changes were short term and in the extended high-frequency range. CONCLUSIONS: There seemed to be inconsistencies regarding the utilization of methods of measuring exposure and outcome between studies. This might be one reason for the differing results in studies on the reported impact on hearing function from recreational noise exposure. To draw more certain conclusions about long-term effects, there is a need for longitudinal research that utilizes sound level measurements to assess low and high degrees of recreational noise exposure in relation to hearing function. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.25114193.

Use of Diagnostic Audiology and Cochlear Implantation in the US.

This study examined if cochlear implant (CI) use varies geographically within the US and if diagnostic audiology use correlates with CI usage.

Increased reliance on temporal coding when target sound is softer than the background.

Everyday environments often contain multiple concurrent sound sources that fluctuate over time. Normally hearing listeners can benefit from high signal-to-noise ratios (SNRs) in energetic dips of temporally fluctuating background sound, a phenomenon called dip-listening. Specialized mechanisms of dip-listening exist across the entire auditory pathway. Both the instantaneous fluctuating and the long-term overall SNR shape dip-listening. An unresolved issue regarding cortical mechanisms of dip-listening is how target perception remains invariant to overall SNR, specifically, across different tone levels with an ongoing fluctuating masker. Equivalent target detection over both positive and negative overall SNRs (SNR invariance) is reliably achieved in highly-trained listeners. Dip-listening is correlated with the ability to resolve temporal fine structure, which involves temporally-varying spike patterns. Thus the current work tests the hypothesis that at negative SNRs, neuronal readout mechanisms need to increasingly rely on decoding strategies based on temporal spike patterns, as opposed to spike count. Recordings from chronically implanted electrode arrays in core auditory cortex of trained and awake Mongolian gerbils that are engaged in a tone detection task in 10 Hz amplitude-modulated background sound reveal that rate-based decoding is not SNR-invariant, whereas temporal coding is informative at both negative and positive SNRs.