Many cochlear implant users with binaural residual (acoustic) hearing benefit from combining electric and acoustic stimulation (EAS) in the implanted ear with acoustic amplification in the other. These bimodal EAS listeners can potentially use low-frequency binaural cues to localize sounds. However, their hearing is generally asymmetric for mid- and high-frequency sounds, perturbing or even abolishing binaural cues. Here, we investigated the effect of a frequency-dependent binaural asymmetry in hearing thresholds on sound localization by seven bimodal EAS listeners. Frequency dependence was probed by presenting sounds with power in low-, mid-, high-, or mid-to-high-frequency bands. Frequency-dependent hearing asymmetry was present in the bimodal EAS listening condition (when using both devices) but was also induced by independently switching devices on or off. Using both devices, hearing was near symmetric for low frequencies, asymmetric for mid frequencies with better hearing thresholds in the implanted ear, and monaural for high frequencies with no hearing in the non-implanted ear. Results show that sound-localization performance was poor in general. Typically, localization was strongly biased toward the better hearing ear. We observed that hearing asymmetry was a good predictor for these biases. Notably, even when hearing was symmetric a preferential bias toward the ear using the hearing aid was revealed. We discuss how frequency dependence of any hearing asymmetry may lead to binaural cues that are spatially inconsistent as the spectrum of a sound changes. We speculate that this inconsistency may prevent accurate sound-localization even after long-term exposure to the hearing asymmetry.

When listening to a sound source in everyday situations, typical movement behavior is highly individual and may not result in the listener directly facing the sound source. Behavioral differences can affect the performance of directional algorithms in hearing aids, as was shown in previous work by using head movement trajectories of normal-hearing (NH) listeners in acoustic simulations for noise-suppression performance predictions. However, the movement behavior of hearing-impaired (HI) listeners with or without hearing aids may differ, and hearing-aid users might adapt their self-motion to improve the performance of directional algorithms. This work investigates the influence of hearing impairment on self-motion, and the interaction of hearing aids with self-motion. In order to do this, the self-motion of three HI participant groups----aided with an adaptive differential microphone (ADM), aided without ADM, and unaided-was measured and compared to previously measured self-motion data from younger and older NH participants. Self-motion was measured in virtual audiovisual environments (VEs) in the laboratory, and the signal-to-noise ratios (SNRs) and SNR improvement of the ADM resulting from the head movements of the participants were estimated using acoustic simulations. HI participants did almost all of the movement with their head and less with their eyes compared to NH participants, which led to a 0.3 dB increase in estimated SNR and to differences in estimated SNR improvement of the ADM. However, the self-motion of the HI participants aided with ADM was similar to that of other HI participants, indicating that the ADM did not cause listeners to adapt their self-motion.

The auditory processing is related to certain skills such as speech recognition in noise. The HINT-Brazil test allows the measurement of the Speech/Noise ratio however there are no studies in the national literature that establish parameters for the child population.

(1) Background: Several types of hearing aids are available for the rehabilitation of vestibular-schwannoma (VS)-related hearing loss. There is a lack of recently published papers regarding this theme. The aim of the present work is to organize current knowledge. (2) Methods: A review of the literature regarding the topics "vestibular schwannoma", "hearing loss", and "hearing aid" was performed. Nineteen studies were thus considered. (3) Results: Conventional hearing aids, contralateral routing of signal (CROS) aids, bone anchored hearing aids (BAHA), and others are available options for hearing rehabilitation in VS patients. The speech discrimination score (SDS) is considered the best measure to assess candidacy for rehabilitation with hearing aids. The best hearing rehabilitative conditions in VS patients when using conventional hearing aid devices are a mild-moderate hearing loss degree with good word recognition (more than 50% SDS). CROS-Aid and BAHA are reported to be beneficial. CROS-Aid expands on the area of receiving hearing. BAHA aids use direct bone-conduction stimulation. Unfortunately, there are no available studies focused specifically on VS patients that compare CROS and BAHA technologies. (4) Conclusions: Hearing aids, CROS, and BAHA are viable options for rehabilitating hearing impairment in VS, but require an accurate case-by-case audiological evaluation for rehabilitating hearing impairment in VS. Further studies are needed to prove if what is currently known about similar hearing illnesses can be confirmed, particularly in the case of VS.

Occupational activities performed by sound engineers are associated with hearing loss. However, there is a dearth of research on the hearing functions and the related hearing loss for sound engineers.

There is a long-standing tradition to assess hearing-aid benefits using lab-based speech intelligibility tests. Towards a more everyday-like scenario, the current study investigated the effects of hearing-aid amplification and noise on face-to-face communication between two conversational partners. Eleven pairs, consisting of a younger normal-hearing (NH) and an older hearing-impaired (HI) participant, solved spot-the-difference tasks while their conversations were recorded. In a two-block randomized design, the tasks were solved in quiet or noise, both with and without the HI participant receiving hearing-aid amplification with active occlusion cancellation. In the presence of 70 dB SPL babble noise, participants had fewer, slower, and less well-timed turn-starts, while speaking louder with longer inter-pausal units (IPUs, stretches of continuous speech surrounded by silence) and reducing their articulation rates. All these changes are indicative of increased communication effort. The timing of turn-starts by the HI participants exhibited more variability than that of their NH conversational partners. In the presence of background noise, the timing of turn-starts by the HI participants became even more variable, and their NH partners spoke louder. When the HI participants were provided with hearing-aid amplification, their timing of turn-starts became faster, they increased their articulation rate, and they produced shorter IPUs, all indicating reduced communication effort. In conclusion, measures of the conversational dynamics showed that background noise increased the communication effort, especially for the HI participants, and that providing hearing-aid amplification caused the HI participant to behave more like their NH conversational partner, especially in quiet situations.

Little is known about the perception of artificial spatial hearing by hearing-impaired subjects. The purpose of this study was to investigate how listeners with hearing disorders perceived the effect of a spatialization feature designed for wireless microphone systems. Forty listeners took part in the experiments. They were arranged in four groups: normal-hearing, moderate, severe, and profound hearing loss. Their performance in terms of speech understanding and speaker localization was assessed with diotic and binaural stimuli. The results of the speech intelligibility experiment revealed that the subjects presenting a moderate or severe hearing impairment better understood speech with the spatialization feature. Thus, it was demonstrated that the conventional diotic binaural summation operated by current wireless systems can be transformed to reproduce the spatial cues required to localize the speaker, without any loss of intelligibility. The speaker localization experiment showed that a majority of the hearing-impaired listeners had similar performance with natural and artificial spatial hearing, contrary to the normal-hearing listeners. This suggests that certain subjects with hearing impairment preserve their localization abilities with approximated generic head-related transfer functions in the frontal horizontal plane.

Directing gaze towards auditory events is a natural behavior. In addition to the well-known accuracy of auditory elicited gaze responses for normal binaural listening, their latency is a measure of possible clinical interest and methodological importance. The aim was to develop a clinically feasible method to assess sound localization latency (SLL), and to study SLL as a function of simulated unilateral hearing loss (SUHL) and the relationship with accuracy. Eight healthy and normal-hearing adults (18-40 years) participated in this study. Horizontal gaze responses, recorded by non-invasive corneal reflection eye-tracking, were obtained during azimuthal shifts (24 trials) of a 3-min continuous auditory stimulus. In each trial, a sigmoid function was fitted to gaze samples. Latency was estimated by the abscissa corresponding to 50% of the arctangent amplitude. SLL was defined as the mean latency across trials. SLL was measured in normal-hearing and simulated SUHL conditions (SUHL30 and SUHL43: mean threshold of 30 dB HL and 43 dB HL across 0.5, 1, 2, and 4 kHz). In the normal-hearing condition, the mean ± SD SLL was 280 ± 40 ms (n = 8) with a test-retest SD = 20 ms. A linear mixed model showed a statistically significant effect of listening condition on SLL. The SUHL30 and SUHL43 conditions revealed a mean SLL of 370 ± 49 ms and 540 ± 120 ms, respectively. Repeated measures correlation analysis showed a clear relationship between SLL and the average sound localization accuracy (R2 = 0.94). The rapid and reliable method to obtain SLL may be an important clinical tool for evaluation of binaural processing. Future studies in clinical cohorts are needed to assess whether SLL may reveal information about binaural processing abilities beyond that afforded by sound localization accuracy.

The purpose of this study was two-fold: 1) to identify differences in the characteristics of adopters and non-adopters of hearing aids (HAs); and 2) to investigate factors influencing the purchase of HA.

This review addresses the advances of our molecular understanding of hearing and how this benefits the hearing impaired. Classical biochemical methods usually fall short in contributing to the analysis of the molecular mechanisms of hearing e. g. in the cochlea, the auditory part of the inner ear, due to the scarcity of the cells of interest. Genetics, molecular cell biology, and physiology, on the other hand, have elucidated the intricate molecular and cellular mechanisms that bring about the outstanding performance of the auditory system. Many of those mechanisms are quite unique and specialized to serve the specific needs of hearing. Hence, their defects often spare other organs and lead to specific non-syndromic deafness. High throughput sequencing can reveal causes of sporadic deafness when combined with careful bioinformatics. Molecular approaches are also helpful for understanding more common forms of hearing impairment such as noise-induced hearing impairment. While molecular therapies are not yet clinically available, careful molecular genetic analysis helps to counsel the hearing impaired subjects.

Neuroglobin (Ngb) is a member of the globin family of respiratory proteins, which was recently observed in many neurons of the auditory pathways. Up to now, however, nothing was known about the role of Ngb in hearing processes. We therefore studied auditory function by recording distortion-product otoacoustic emissions (DPOAE) and auditory brainstem responses (ABRs) in wild-type (C57BL/6N) and Ngb-knockout mice. In KO mice, DPOAE thresholds were moderately augmented in the range of 5-18 kHz, reaching statistical significance at 8 and 10 kHz, while the ABR thresholds were not different between groups. The activation of the efferent system by an additional noise given to the contralateral ear resulted in an increased f2-f1-emission level only in WT animals. A noise exposure resulted in similar acute threshold shifts in the DPOAE and ABR of both animal groups. The recovery of hearing function, expressed by decreased DPOAE thresholds, was not significantly different between groups after four days and after four weeks. ABR recordings showed that threshold shifts elicited by noise-trauma were slightly better revised in wild-type mice. While ABR amplitudes were similar in both groups before noise overexposure, four weeks after trauma a moderate but statistically significant decrease of the latest peak-to-peak response amplitude (originating in the inferior colliculus) was observed in KO mice. Our results suggest that the lack of Ngb, at least in the model used in the present study, results in only marginal deficits in hearing ability. A putative functional role of Ngb in the efferent system warrants further studies.

Age-related hearing loss typically affects the hearing of high frequencies in older adults. Such hearing loss influences the processing of spoken language, including higher-level processing such as that of complex sentences. Hearing aids may alleviate some of the speech processing disadvantages associated with hearing loss. However, little is known about the relation between hearing loss, hearing aid use, and their effects on higher-level language processes. This neuroimaging (fMRI) study examined these factors by measuring the comprehension and neural processing of simple and complex spoken sentences in hard-of-hearing older adults (n = 39). Neither hearing loss severity nor hearing aid experience influenced sentence comprehension at the behavioral level. In contrast, hearing loss severity was associated with increased activity in left superior frontal areas and the left anterior insula, but only when processing specific complex sentences (i.e. object-before-subject) compared to simple sentences. Longer hearing aid experience in a sub-set of participants (n = 19) was associated with recruitment of several areas outside of the core speech processing network in the right hemisphere, including the cerebellum, the precentral gyrus, and the cingulate cortex, but only when processing complex sentences. Overall, these results indicate that brain activation for language processing is affected by hearing loss as well as subsequent hearing aid use. Crucially, they show that these effects become apparent through investigation of complex but not simple sentences.

This manuscript examines the issue of potential decline in hearing sensitivity due to hearing aid usage through an analysis of data obtained from the temporary threshold shift (TTS) paradigm. Following a critique of the traditional measures of TTS, the concept of integrated TTS (ITTS) is reviewed and data on hearing-aid-induced ITTS are presented. In addition, a series of equations relating permanent threshold shift (PTS) to a recently developed measure of noise dose (Dn) is derived and predictions for hearing-aid-induced PTS are made. Recommended gain settings established to protect the hearing of a person wearing a hearing aid from further decline following various durations of hearing aid usage are also provided.

To identify predictors of the 5-year uptake of hearing aids (HAs) and hearing assistive technology (HAT) in a sample of Dutch employees eligible for HAs and/or HAT. The potential predictors included demographic factors (age, sex, marital status, and living situation), education, hearing factors (ability to recognize speech in noise and self-reported hearing disability), distress, self-efficacy, and work-related factors (job demand, job control, and need for recovery).

By means of a questionnaire it was investigated how in individuals who had previously had normal hearing deafness influences their pleasure and habits in listening to music, and which role a hearing aid can play in this respect. Out of 330 questionnaires returned, 206 could be statistically evaluated. 95% reported that formerly they had liked music, light music coming from the radio being the most frequently mentioned type of music and medium. 36% had formerly played an instrument or had enjoyed singing. 79% feel that their deafness has affected their pleasure in listening to music. Most common complaints refer to the fact that everything sounds distorted and wrong, melodies cannot be recognised any longer, the text of songs is not understood. 60% are fitted with one hearing aid, 40% have binaural hearing aids. 67% report that the hearing aid has rendered listening to music again more pleasurable, and 74% use their hearing aid more or less regularly when listening to music. The distorted sound and the fast alternating between "too soft" and "too loud", forcing the subject to continually adjusting his hearing aid, seem to be among the most annoying features.

Individuals with the same ability of speech recognition in quiet can have extremely different results in noisy environments.

Congenital cytomegalovirus (cCMV) is the most common cause of nongenetic sensorineural hearing loss (SNHL) in children. We examined the longitudinal hearing outcomes of children with cCMV in relation to their newborn hearing screening findings, and their use of antiviral therapy.

In recent years, a growing body of literature has explored the effect of hearing impairment on the neural processing of speech, particularly related to the neural tracking of speech envelopes. However, only limited work has focused on the potential usage of the method for evaluating the effect of hearing aids designed to amplify and process the auditory input provided to hearing-impaired listeners. The current study investigates how directional sound processing in hearing-aids, denoted directionality, affects the neural tracking and encoding of speech in EEG recorded from 11 older hearing-impaired listeners. Behaviorally, the task performance improved when directionality was applied, while subjective ratings of listening effort were not affected. The reconstruction of the to-be-attended speech envelopes improved significantly when applying directionality, as well as when removing the background noise altogether. When inspecting the modelled response of the neural encoding of speech, a faster transition was observed between the early bottom-up response and the later top-down attentional-driven responses when directionality was applied. In summary, hearing-aid directionality affects both the neural speech tracking and neural encoding of to-be-attended speech. This result shows that hearing-aid signal processing impacts the neural processing of sounds and that neural speech tracking is indicative of the benefits associated with applying hearing-aid processing algorithms.

Preference for noise reduction (NR) strength differs between individuals. The purpose of this study was (1) to investigate whether hearing loss influences this preference, (2) to find the number of distinct settings required to classify participants in similar groups based on their preference for NR strength, and (3) to estimate the number of paired comparisons needed to predict to which preference group a participant belongs. A paired comparison paradigm was used in which participants listened to pairs of speech-in-noise stimuli processed by NR with 10 different strength settings. Participants indicated their preferred sound sample. The 30 participants were divided into three groups according to hearing status (normal hearing, mild hearing loss, and moderate hearing loss). The results showed that (1) participants with moderate hearing loss preferred stronger NR than participants with normal hearing; (2) cluster analysis based solely on the preference for NR strength showed that the data could be described well by dividing the participants into three preference clusters; (3) the appropriate cluster membership could be found with 15 paired comparisons. We conclude that on average, a higher hearing loss is related to a preference for stronger NR, at least for our NR algorithm and our participants. The results show that it might be possible to use a limited set of pre-set NR strengths that can be chosen clinically. For our NR one might use three settings: no NR, intermediate NR, and strong NR. Paired comparisons might be used to find the optimal one of the three settings.

Hearing loss is associated with poor cognitive performance and incident dementia and may contribute to cognitive decline. Treating hearing loss with hearing aids may ameliorate cognitive decline. The purpose of this study was to test whether use of hearing aids was associated with better cognitive performance, and if this relationship was mediated via social isolation and/or depression. Structural equation modelling of associations between hearing loss, cognitive performance, social isolation, depression and hearing aid use was carried out with a subsample of the UK Biobank data set (n = 164,770) of UK adults aged 40 to 69 years who completed a hearing test. Age, sex, general health and socioeconomic status were controlled for as potential confounders. Hearing aid use was associated with better cognition, independently of social isolation and depression. This finding was consistent with the hypothesis that hearing aids may improve cognitive performance, although if hearing aids do have a positive effect on cognition it is not likely to be via reduction of the adverse effects of hearing loss on social isolation or depression. We suggest that any positive effects of hearing aid use on cognition may be via improvement in audibility or associated increases in self-efficacy. Alternatively, positive associations between hearing aid use and cognition may be accounted for by more cognitively able people seeking and using hearing aids. Further research is required to determine the direction of association, if there is any direct causal relationship between hearing aid use and better cognition, and whether hearing aid use results in reduction in rates of cognitive decline measured longitudinally.