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Hybrid spin-mechanical systems offer a promising platform for advancing quantum science and technology. However, practical implementation of applications within these hybrid quantum systems demands the seamless integration of supplementary physical components. In this context, we present a proposal for a multi-mode spin-mechanical setup, featuring the utilization of three-mode coupling nanomechanical carbon nanotube (CNT) resonators. These resonators interact with each other via a phase-dependent phonon-exchange mechanism, which is coupled to the same nitrogen vacancy (NV) centers in diamond. Based on the modulation of the phonon–phonon coupling phase and leveraging the triple Fano-like resonance phenomenon, a tripling of electromagnetically induced transparency (EIT) becomes achievable within the system. This tripling is accompanied by swift dispersion, leading to a subtle advancement or delay in outcomes. The phenomenon of triple Fano-like resonance, alongside the resulting triple EIT, engenders noteworthy slow-to-fast and fast-to-slow light effects, which is theoretically demonstrated in CNT resonators, with both identical and distinct frequencies. The findings underscore that CNT resonators with varying frequencies can evoke a more pronounced transition in the slow–fast–slow and fast–slow–fast light effects. This study lays the foundation for the application of phonon-mediated optical information storage and processing. [ABSTRACT FROM AUTHOR]

Hearing mediates many behaviours critical for survival in echolocating bats, including foraging and navigation. Although most mammals are susceptible to progressive age-related hearing loss, the evolution of biosonar, which requires the ability to hear low-intensity echoes from outgoing sonar signals, may have selected against the development of hearing deficits in bats. Many echolocating bats exhibit exceptional longevity and rely on acoustic behaviours for survival to old age; however, relatively little is known about the ageing bat auditory system. In this study, we used DNA methylation to estimate the ages of wild-caught big brown bats (Eptesicus fuscus) and measured hearing sensitivity in young and ageing bats using auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). We found no evidence for hearing deficits in bats up to 12.5 years of age, demonstrated by comparable thresholds and similar ABR and DPOAE amplitudes across age groups. We additionally found no significant histological evidence for cochlear ageing, with similar hair cell counts, afferent and efferent innervation patterns in young and ageing bats. Here, we demonstrate that big brown bats show minimal evidence for age-related hearing loss and therefore represent informative models for investigating mechanisms that may preserve hearing function over a long lifetime. [ABSTRACT FROM AUTHOR]

BACKGROUND: Varied noise environments, such as impulse noise and steady-state noise, may induce distinct patterns of hearing impairment among personnel exposed to prolonged noise. However, comparative studies on these effects remain limited. OBJECTIVE: This study aims to delineate the different characteristics of hearing loss in workers exposed to steady-state noise and impulse noise. METHODS: As of December 2020, 96 workers exposed to steady-state noise and 177 workers exposed to impulse noise were assessed. Hearing loss across various frequencies was measured using pure tone audiometry and distortion product otoacoustic emission (DPOAE) audiometry. RESULTS: Both groups of workers exposed to steady-state noise and impulse noise exhibited high frequencies hearing loss. The steady-state noise group displayed significantly greater hearing loss at lower frequencies in the early stages, spanning 1– 5 years of work (P < 0.05). Among individuals exposed to impulse noise for extended periods (over 10 years), the observed hearing loss surpassed that of the steady-state noise group, displaying a statistically significant difference (P < 0.05). CONCLUSION: Hearing loss resulting from both steady-state noise and impulse noise predominantly occurs at high frequencies. Early exposure to steady-state noise induces more pronounced hearing loss at speech frequencies compared to impulse noise. [ABSTRACT FROM AUTHOR]

The study "Energy exchanges between coherent modes in the near wake of a wind turbine model at different tip speed ratios" examines the spatio-temporal nature of coherent modes in wind turbine wakes using particle image velocimetry experiments. The research reveals that the tip vortex system in wind turbine wakes exchanges energy primarily through the turbine's rotational frequency, with the onset location of wake recovery shifting with the tip speed ratio. The study provides valuable insights into the complex network of energy transfers in wind turbine wakes, shedding light on the dynamics of fluid flows and their applications in engineering and environmental systems. [Extracted from the article]

Hearing problems in children impact development, especially speech and language. Some risk factors are known to influence the occurrence of congenital deafness. For the last five years, screening with Otoacoustic Emissions (OAE) and Brainstem Evoked Response Audiometry (BERA) examinations has been used at Dustira Hospital to make a diagnosis and intervene as early as possible. This study aims to obtain the prevalence, risk factors, and OAE and BERA examination results at Dustira Cimahi Hospital. A retrospective descriptive study was conducted on children who underwent the OAE and BERA examination by collecting subject data for the period of January 2020-- December 2022. The OAE examination uses distortion product otoacoustic emissions, while the BERA examination is based on the International Standard Organization (ISO). Of the 42 patients who were screened for hearing loss, the 3--5-year-old group was the most dominant (40.4%). Most of the patients were male (66%). While the prenatal risk factor was a history of TORCH infection (12%), the perinatal risk factor was low birth weight (14.2%) and the postnatal risk factor was hyperbilirubinemia (19%). The majority of the OAE examination results were refers found at 32 people (76.1%). The results of the BERA click examination were the presence of wave V found in 38 people (90.4%)). Patients with suspected congenital deafness who underwent hearing screening were in the age range of 3--5 years and were all male. The risk factors found were a history of TORCH infection, low birth weight, and hyperbilirubinemia. The majority of the results of the OAE examination was refer and that of the BERA was wave V. [ABSTRACT FROM AUTHOR]

Measuring and analyzing both nonlinear-distortion and linear-reflection otoacoustic emissions (OAEs) combined creates what we have termed a "joint-OAE profile." Here, we test whether these two classes of emissions have different sensitivities to hearing loss and whether our joint-OAE profile can detect mild-moderate hearing loss better than conventional OAE protocols have. 2f1-f2 distortion-product OAEs and stimulus-frequency OAEs were evoked with rapidly sweeping tones in 300 normal and impaired ears. Metrics included OAE amplitude for fixed-level stimuli as well as slope and compression features derived from OAE input/output functions. Results show that mild-moderate hearing loss impacts distortion and reflection emissions differently. Clinical decision theory was applied using OAE metrics to classify all ears as either normal-hearing or hearing-impaired. Our best OAE classifiers achieved 90% or better hit rates (with false positive rates of 5%–10%) for mild hearing loss, across a nearly five-octave range. In summary, results suggest that distortion and reflection emissions have distinct sensitivities to hearing loss, which supports the use of a joint-OAE approach for diagnosis. Results also indicate that analyzing both reflection and distortion OAEs together to detect mild hearing loss produces outstanding accuracy across the frequency range, exceeding that achieved by conventional OAE protocols. [ABSTRACT FROM AUTHOR]

Introduction: Schizophrenia patients have cognitive issues, such as attention deficits. Cognitive activity controls the micromechanics of cochlear outer hair cells (OHC). We integrated alternate auditory attention (ALAUDIN) tasks and contralateral suppression of otoacoustic emissions (CSOAE) to measure OHC micromechanics. Materials and methods: The ALAUDIN tasks' reliability has been evaluated in ten normal-hearing ears. Then, 36 healthy controls and 8 schizophrenia patients with normal auditory function has been included. The OAE amplitude was initially measured with 60 dB peak SPL clicks in the test ear without contralateral suppressors (CS) and re-measured with four types of CS, namely White Noise (CS1), White Noise + Attention Task I (CS2), White Noise + Attention Task II (CS3) and White Noise + Attention Task III (CS4), delivered randomly to non-test ears at 75 dB SPL. Suppression is a positive difference in OAE amplitudes with and without CS. Statistical analysis included Bayesian independent sample t-tests to compare suppression between groups and ears, as well as Bayesian repeated measures ANOVA to assess differences in suppression among various stimuli for all groups. Results: Interclass correlation showed moderate to high reliability across all CS. In the schizophrenia group, CS4 had the highest TEOAE suppression value. Suppression in schizophrenia is larger than healthy control in all stimuli with CS1 and CS4 showing significantly greater suppression. Stimuli did not affect CSOAE across groups. Conclusion: Cognitive deficits in schizophrenia patients may be objectively identified using the integrated ALAUDIN tasks-CSOAE. Their large suppression suggests dysconnectivity among brain regions, resulting in hyperactivity of the efferent pathway. [ABSTRACT FROM AUTHOR]

Aim: Crimean-Congo Hemorrhagic Fever (CCHF) is a tick-borne viral disease, and Sensorineural Hearing Loss (SNHL) arises from pathologies in the cochlea or retrocochlear pathways. Viral infections, including Crimean-Congo hemorrhagic fever are considered possible etiological factors for Sensorineural hearing loss, as endothelial damage in Crimean-Congo hemorrhagic fever may impair inner ear blood flow. This study aimed to differentiate between cochlear and retrocochlear hearing loss in patients with Crimean- Congo hemorrhagic fever and assess the reliability of Auditory Steady-State Response (ASSR) testing by comparing its results with pure-tone audiometry. Materials and Methods: The study included 30 Crimean-Congo hemorrhagic fever patients (Group CCHF) and 30 healthy controls (Group C). Hearing measurements were conducted using pure tone audiometry, otoacoustic emissions, tympanometry, and Auditory steady-state response before the patients' discharge. Data were analyzed using SPSS 22.0. Results: The results showed no significant difference in audiometric thresholds between the right and left ears of Group CCHF at various frequencies. However, Auditory steady-state response results at 1000, 2000, and 4000 Hz in the right ear and at all tested frequencies in the left ear revealed significant differences between groups (p<0.05). Conclusion: While this study did not establish a clear link between Crimean-Congo hemorrhagic fever and Sensorineural hearing loss, it suggests the need for further research with larger samples and testing during both the active and recovery phases of Crimean-Congo hemorrhagic fever. [ABSTRACT FROM AUTHOR]

Studies about the effects of SARS-CoV-2 on pregnant women and children born to positive women are controversial with regard to possible inner ear-related damage but most of them do not detect the involvement of this virus in auditory function. However, only a few studies on long-term effects on language development are currently available because of the recent onset of the pandemic. The aim of this study was to investigate the impact of SARS-CoV-2 infection on perceptual and expressive abilities and the emerging development of communication in young children. To this purpose, the MacArthur–Bates Communicative Development Inventory—Words and Gestures form (CDI-WG), was administered to parents. In total, 115 children whose mother was infected by SARS-CoV-2 during pregnancy were enrolled in the study and evaluated at the Audiology Service of the Modena University Hospital. All children underwent Otoacoustic Emissions (OAE) at birth: 114/115 had a "pass" result bilaterally, while 1 case had a unilateral "refer" result. Overall, 110/115 newborns (95.65%) underwent audiological evaluation between 10–18 months of age. In 5/110 patients (3.6%), the Pure Tone Average (PTA) result was equal to 35 dB; one case had a hearing threshold of around 50 dB due to a bilateral effusive otitis media. A notable finding was the percentage of children with tubal dysfunction in both evaluations, within 2 months of age and around 12 months of age. Most children revealed normal hearing. The CDI-WG was completed by 56/115 families. The rate of children below the fifth percentile was 8.9% for sentences understood, 12.5% for words understood, and 5.4% for words produced. Concerning CDI-Gestures, only 2 children (3.6%) were below the fifth percentile. A structured audiological follow-up in association with the evaluation of communication skills of children appears fundamental, particularly in the years of maximum neuroplasticity. Long-term studies are still necessary to evaluate the possible consequences of the pandemic. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the cochlea, medial olivocochlear system, and brainstem function in autistic children using evoked otoacoustic emissions (OAEs) and a noninvasive contralateral suppression (CLS) test. In total, we included 21 autistic children with normal hearing (study group) and 11 healthy children (control group). Transient-evoked OAEs (TEOAEs) and CLS of TEOAE were evaluated in the left and right ears of all patients. In a silent room, spontaneous, transient, and dP ILO292 were evaluated. The mean age of the study and control group was 9.1 years (range: 6-13 and 6-12 years, respectively). For the study group, there was no statistically significant difference between the OAE and CLS values of the right ear (P >.05). However, for the left ears, OAE values were statistically significantly higher than the CLS values (P <.05). In the control group, the OAE values of both ears were statistically significantly higher than the CLS values (P <.05). In autistic children with normal hearing, the medial olivocochlear system functions more effectively in the right ear than the left ear. Asymmetry between the ears is likely responsible for the peripheral auditory lateralization and independence in auditory function between the left and right ears. [ABSTRACT FROM AUTHOR]

Yakshagana is an India's traditional folk theatre musical dance drama. The purpose of the study is to profile audiological characteristics and document hearing-related symptoms in Yakshagana artists. A cross-sectional study was performed on 96 Yakshagana artists. Participants' demographic data were captured, and audiological evaluations, including high frequency audiometry (HFA), tympanometry, acoustic reflex threshold and transient evoked otoacoustic emission (TEOAE), were performed. The majority of the individuals had minimal and mild hearing loss. The mean scores of pure tone thresholds were greater at 4 kHz and 8 kHz. The majority of the HFA thresholds at 10 kHz, 12.5 kHz, and 16 kHz indicated no responses, which can be accredited to the fact that noise-induced hearing loss (NIHL) first affects the higher frequencies. TEOAE analysis showed a greater percentage of failures in the higher frequencies, particularly at 3 and 4 kHz in both ears, which can be an indicator of bilateral cochlear damage. These findings indicate that Yakshagana artists are at risk of hearing loss due to noise exposure. Hearing evaluation and regular monitoring of hearing thresholds is advisable for this population as it can impact their careers. [ABSTRACT FROM AUTHOR]

Aim: To estimate the Single-sided deafness (SSD) among sensorineural hearing loss (SNHL) in Tertiary Care Rehabilitation Centre. To determine the audiological characteristics, associated and medical problems, and rehabilitative approaches among SSD. Method: A retrospective study was conducted to report on demographic details, audiological evaluation, and hearing aid management among SSD clients. A total of 11,534 cases of SNHL were reported to the Audiology department at the tertiary care rehabilitative center at Mysuru between January 2014 and December 2017. Results: A total of 225 were diagnosed as having SSD, accounting for approximately two cases of SSD in a cohort of 100 SNHL cases (225/11,534*100). In addition, males are affected more than females. SSD is found to have more in the right ear than the left ear. Their major complaints were tinnitus and vertigo, apart from reduced hearing sensitivity from the affected ear. In the side of the ear with profound hearing loss among SSD clients showed normal middle ear status with absent acoustic reflexes, otoacoustic emissions, and auditory brainstem response. Only 54 individuals (24%) out of 225 SSD clients underwent a hearing aid trial. Twenty-one (9%) SSD clients purchased a hearing aid, and a minuscule seven (3%) of 225 SSD clients are using a hearing aid. The preference for hearing aid uptake was low because of the experience of vibratory sensation and having near-normal hearing in one ear. Conclusion: Two cases of SSD were observed among SNHL and they are less likely to get benefits from the hearing aid. [ABSTRACT FROM AUTHOR]

To assess deafness in term infant with birth asphyxia by otoacoustic emission and brain stem evoked response audiometry. A Prospective observational study was done at Tertiary care government hospital from 15/02/2021 to 15/10/2022.Total 130 patients were included in the study by consecutive sampling method. All the patients fulfilling the inclusion criteria during the study period were included. After explaining the aims, objectives and methods of study, written informed consent was obtained from the parents to undergo Otoacoustic Emission (OAE) and Brain Stem Evoked Response Audiometry Test (BERA). Data was entered in case record form. Collected data was analysed by appropriate statistical methods. Hearing impairment was present in eight (6.15%) asphyxiated term infants. A mild degree of hearing loss was seen in three (37.5%), a moderate degree of hearing loss was seen in four (50%), severe degree of hearing loss was seen in one (12.5%) asphyxiated term infant. In asphyxiated term infants, no significant difference in hearing loss was seen with respect to gender, Obstetrics history, and type of delivery. Significant difference in hearing loss was seen in antenatal Diabetes mellitus, hypertension, family history of SNHL and APGAR Score less than 6. Severe degree of hearing loss was seen in prolonged labour and HTN mother. Significant difference in hearing loss was seen in antenatal Diabetes mellitus, hypertension, family history of SNHL and APGAR Score less than 4 and 6 in one and five minutes respectively. Severe degree of hearing loss was seen in prolonged labour and HTN mother. [ABSTRACT FROM AUTHOR]

Gene therapy has made significant progress in the treatment of hereditary hearing loss. However, most research has focused on deafness-related genes that are primarily expressed in hair cells with less attention given to multisite-expressed deafness genes. MPZL2 , the second leading cause of mild-to-moderate hereditary deafness, is widely expressed in different inner ear cells. We generated a mouse model with a deletion in the Mpzl2 gene, which displayed moderate and slowly progressive hearing loss, mimicking the phenotype of individuals with DFNB111. We developed a gene replacement therapy system mediated by AAV-ie for efficient transduction in various types of cochlear cells. AAV-ie- Mpzl2 administration significantly lowered the auditory brainstem response and distortion product otoacoustic emission thresholds of Mpzl2 −/− mice for at least seven months. AAV-ie- Mpzl2 delivery restored the structural integrity in both outer hair cells and Deiters cells. This study suggests the potential of gene therapy for MPZL2 -related deafness and provides a proof of concept for gene therapy targeting other deafness-related genes that are expressed in different cell populations in the cochlea. [Display omitted] MPZL2 is widely expressed in various inner ear cells, and its mutations are the second leading cause of mild-to-moderate hereditary deafness. Here, the authors developed a gene replacement therapy system using AAV-ie with wide tropism in the inner ear, which restored hearing and structural integrity in Mpzl2 −/− mice. [ABSTRACT FROM AUTHOR]

Purpose: The auditory brainstem response (ABR) can be elicited by broadband stimuli such as the click and chirp. Differences in the click- and chirp-evoked ABR have been extensively described using subjective analyses. The aim of the current research is to determine if subjectively observed differences between the click- and chirp-evoked ABR are also represented in objective signal-tonoise ratio (SNR) measurements obtained from these responses at different stimulus intensities and sweep counts. Method: ABRs were collected using click and chirp stimuli on nine adults with normal hearing sensitivity. Three SNR methods (split-sweep average--based SNR [SSA-SNR], F ratio--based single-point [Fsp], and multipoint [Fmp]) were used for the objective analysis of the waveforms at four stimulus intensities (20, 40, 60, and 80 dB nHL) and five sweep counts (100, 200, 300, 400, and 500 sweeps). Results: SSA-SNR measurements were statistically stronger for chirp- as compared to click-evoked ABRs. Additionally, chirp/click SSA-SNR, Fsp, and Fmp ratio measurements were consistently greater than 1. The advantage associated with the chirp was most noticeable at moderate stimulus intensities for all three measurements. Discussion: The advantages for the chirp observed here could have implications for threshold estimation and screening ABR tests. Furthermore, when stimulus intensity and sweep count were varied, general response trends suggest that the three SNR-based methods performed similarly to each other, as well as to traditionally used subjective measures, suggesting that these techniques have the potential to be used effectively in clinic. [ABSTRACT FROM AUTHOR]

Objectives The study aimed to explore the impact of various head positions on the distortion product otoacoustic emissions (DPOAE) amplitudes, identifying the specific DPOAE frequencies showing the effect was also of interest. Materials and Methods DPOAEs were recorded from the right ears of 50 normal-hearing individuals in six head positions, supine, and five sitting positions (head erect, roll left, roll right, pitch backward, and pitch forward). DPOAEs were averaged and measured for their overall and frequency-specific amplitudes at 1 kHz, 1.5 kHz, 2 kHz, 3 kHz, 4 kHz, 6 kHz, and 8 kHz. Statistical Analysis To investigate the statistical significance of the observed mean differences, the data was tested using repeated measures of analysis of variance (ANOVA) following the Shapiro–Wilk normality test. The pair-wise comparison was tested using the Bonferroni post-hoc test and one-sided Bayesian paired sample t-test. Results The results of ANOVA revealed a significant main effect of head posture only at 1 kHz. The Bonferroni post-hoc test and one-sided Bayesian paired sample t-test results showed significantly higher DPOAE amplitude in the head erect compared to the supine position. There were no significant differences between other pairs of head postures. Conclusion Head posture is a trivial influencing factor of DPOAEs and hence, does not require consideration in interpreting DPOAEs. [ABSTRACT FROM AUTHOR]

The human medial olivocochlear (MOC) reflex was assessed by observing the effects of contralateral acoustic stimulation (CAS) on the cochlear microphonic (CM) across a range of probe frequencies. A frequency-swept probe tone (125–4757 Hz, 90 dB SPL) was presented in two directions (up sweep and down sweep) to normal-hearing young adults. This study assessed MOC effects on the CM in individual participants using a statistical approach that calculated minimum detectable changes in magnitude and phase based on CM signal-to-noise ratio (SNR). Significant increases in CM magnitude, typically 1–2 dB in size, were observed for most participants from 354 to 1414 Hz, where the size and consistency of these effects depended on participant, probe frequency, sweep direction, and SNR. CAS-related phase lags were also observed, consistent with CM-based MOC studies in laboratory animals. Observed effects on CM magnitude and phase were in the opposite directions of reported effects on otoacoustic emissions (OAEs). OAEs are sensitive to changes in the motility of outer hair cells located near the peak region of the traveling wave, while the effects of CAS on the CM likely originate from MOC-related changes in the conductance of outer hair cells located in the basal tail of the traveling wave. Thus, MOC effects on the CM are complementary to those observed for OAEs. [ABSTRACT FROM AUTHOR]

Background: The study explored the differences in audiological and non-audiological characteristics between congenital, early-onset, and late-onset auditory neuropathy spectrum disorder (ANSD). Ninety-five individuals diagnosed with ANSD were included in the study. They were divided into three groups congenital ANSD—children (30 individuals, 60 ears), adults with early-onset ANSD (30 individuals, 56 ears), and adults with late-onset ANSD (35 individuals, 62 ears). The non-audiological characteristics (gender, laterality, and risk factors) and audiological characteristics (behavioral and electrophysiological measures) were compared between the three groups. Results: Discriminant analyses showed that the pure tone average, audiogram configuration, and speech thresholds were the best auditory predictors of onset-based group differences in ANSD (congenital and early-onset versus late-onset ANSD). While the congenital and early-onset group showed poorer pure-tone and speech thresholds, along with flat configuration, the late-onset group demonstrated relatively better thresholds and other configurations (rising, tent-shaped, cookie-bite). In addition, long latency responses were delayed or absent in children with congenital ANSD, indicative of onset coding deficits at the cortical level. Conclusions: The study highlights the audiological differences between congenital, early-, and late-onset ANSD groups. These differences could be because of variations in etiology, pathophysiology, site of lesion, or genetic variability between the groups, which needs to be explored further. [ABSTRACT FROM AUTHOR]

Introduction: Pulmonary exacerbations increase the requirement of aminoglycoside (AG) antibiotics in people with cystic fibrosis (pwCF). Several studies have shown that AGs have a cumulative effect on ototoxicity. We aimed to investigate the relationship between AG exposure and ototoxicity by using 3 different methods in patients with CF. Materials/Methods: The multicenter study included 121 pwCF aged between 5 and 18 years with a history of parenteral AG exposure. Standard pure-tone audiometry, extended high-frequency pure-tone audiometry (EHF-PTA), and distortion-product otoacoustic emissions (DPOAE) tests were performed. Mitochondrial mutation analysis for m1555G>A was performed in 61 patients. Results: Median age was 12.85 years and 52.1% (n = 63) were male. 18.2% (n = 22) of the patients had received parenteral AGs more than 5 courses/lifetime. Ototoxicity was detected in at least one of the tests in 56.2% (n = 68) of the patients. Only 10.7% (n = 13) of the patients had reported a symptom indicating ototoxicity. 30.3% (n = 30) of the patients had ototoxicity in the low exposure group, while it was 45.5% (n = 10) in the high exposure group according to EHF-PTA (p > 0.05). Median number of parenteral amikacin courses was significantly higher in the ototoxic group (2 [1.25–5.75] vs. 2 [1–3]; p = 0.045). No m1555A>G mutation was detected in 61 patients who screened for mitochondrial mutation analysis. Conclusion: As AG ototoxicity occurs primarily at high frequencies, EHF-PTA is important in early detecting ototoxicity. EHF-PTA and DPOAE detected ototoxicity in some patients with normal PTA results. All pwCF with a history of AG exposure should be evaluated for hearing loss since symptoms may only be noticed in the late period. [ABSTRACT FROM AUTHOR]

Introduction Auditory injuries induced by repeated exposures to blasts reduce the operational performance capability and the life quality of military personnel. The treatment for blast-induced progressive hearing damage is lacking. We have recently investigated the therapeutic function of liraglutide, a glucagon-like peptide-1 receptor agonist, to mitigate blast-induced hearing damage in the animal model of chinchilla, under different blast intensities, wearing earplugs (EPs) or not during blasts, and drug-treatment plan. The goal of this study was to investigate the therapeutical function of liraglutide by comparing the results obtained under different conditions. Materials and Methods Previous studies on chinchillas from two under-blast ear conditions (EP/open), two blast plans (G1: 6 blasts at 3–5 psi or G2:3 blasts at 15–25 psi), and three treatment plans (blast control, pre-blast drug treatment, and post-blast drug treatment) were summarized. The auditory brainstem response (ABR), distortion product otoacoustic emission (DPOAE), and middle latency response (MLR) recorded within 14 days after the blasts were used. Statistical analysis was performed to evaluate the effect of liraglutide under different conditions Results ABR threshold shifts indicated that the conditions of the EP and open ears were substantially different. Results from EP chinchillas indicated that the pre-blast treatment reduced the acute ABR threshold elevation on the day of blasts, and the significance of such an effect increased with the blast level. Liraglutide-treated open chinchillas showed lower ABR threshold shifts at the later stage of the experiment regardless of the blast levels. The DPOAE was less damaged after G2 blasts compared to G1 when pre-blast liraglutide was administrated. Lower post-blast MLR amplitudes were observed in the pre-blast treatment groups. Conclusions This study indicated that the liraglutide mitigated the blast-induced auditory injuries. In EP ears, the pre-blast administration of liraglutide reduced the severity of blast-induced acute damage in ears with EP protection, especially under G2. In animals with open ears, the effect of liraglutide on the restoration of hearing increased with time. The liraglutide potentially benefits post-blast hearing through multiple approaches with different mechanics. [ABSTRACT FROM AUTHOR]

BACKGROUND: The inner ear is most susceptible to the aging effects. Distortion product otoacoustic emissions (DPOAEs) are a good indicator for interpreting the age effects but are usually recorded at up to 8000 Hz frequencies in routine audiologic testing. The present study was designed to assess and compare the DPOAEs at conventional frequencies and at extended high frequencies (EHFs) across different age groups. METHODS: Extended high-frequency audiometry (9000-16 000 Hz) and DPOAEs from 500-16 000 Hz were recorded on 80 adult (160 ears) participants (15-55 years) with normal hearing sensitivity. The participants were categorized into 4 groups: group I (15-<25 years), group II (25-<35 years), group III (35-<45 years), and group IV (45-55 years). RESULTS: A statistically significant reduction in EHF thresholds was observed from group III onward. However, the thresholds were comparatively better for group III at frequencies 9000, 10 000, and 11 500Hz than group IV. No significant difference was observed for EHF DPOAEs in groups I and II (except at 16 000 Hz) and III and IV. Distortion product otoacoustic emissions at conventional frequencies in group IV were significantly poorer than the other 3 groups. A weak negative correlation was observed between the DPOAE parameters and EHF thresholds. The effect of age was more pronounced on EHF DPOAEs than EHF thresholds for frequencies 9000, 10 000, and 11 500 Hz. CONCLUSION: Distortion product otoacoustic emissions at EHF started deteriorating below the age of 30 years and showed a rapid decline above 35 years. Extended high-frequency DPOAEs can be used as screening tools to assess the function of the basal part of the cochlea. [ABSTRACT FROM AUTHOR]

We studied the function of the auditory system in Wistar rats after repeated intravenous administration of nicotinamide riboside (NR). The functional activity of the receptor and retrocochlear parts of the auditory system were assessed by recording short-latency auditory evoked potentials (SLAEPs) and distortion-product otoacoustic emissions (DPOAEs) at baseline, immediately after NR administration, and 1 and 2 months later. Repeated intravenous NR administration (cumulative dose of 2700 mg/kg) to Wistar rats has a detrimental impact on the structures within the cochlear section of the auditory system. [ABSTRACT FROM AUTHOR]

A speech intelligibility (SI) prediction model is proposed that includes an auditory preprocessing component based on the physiological anatomy and activity of the human ear, a hierarchical spiking neural network, and a decision back-end processing based on correlation analysis. The auditory preprocessing component effectively captures advanced physiological details of the auditory system, such as retrograde traveling waves, longitudinal coupling, and cochlear nonlinearity. The ability of the model to predict data from normal-hearing listeners under various additive noise conditions was considered. The predictions closely matched the experimental test data under all conditions. Furthermore, we developed a lumped mass model of a McGee stainless-steel piston with the middle-ear to study the recovery of individuals with otosclerosis. We show that the proposed SI model accurately simulates the effect of middle-ear intervention on SI. Consequently, the model establishes a model-based relationship between objective measures of human ear damage, like distortion product otoacoustic emissions, and speech perception. Moreover, the SI model can serve as a robust tool for optimizing parameters and for preoperative assessment of artificial stimuli, providing a valuable reference for clinical treatments of conductive hearing loss. [ABSTRACT FROM AUTHOR]

Purpose: This study focused on the selected markers of oxidative stress, impact of elevated lead levels on long-term hearing quality. We investigated whether the presence of certain essential minerals might provide protection to the auditory system against the effects of lead (and cadmium) compounds. Methods: The research group included 280 male employees of the zinc and lead smelter, which was divided into: L-Pb—low blood lead concentration (PbB) subgroup, H-Pb—high PbB subgroup. Hearing tests were performed using the click evoked otoacoustic emission (CEOAE). Results: Zinc protoporphyrin level was significantly higher in the H-Pb subgroup by 68%. Cd concentration was significantly higher in H-Pb by 33%. The Ca concentration was significantly lower in the H-Pb by − 2%. Selected oxidative stress markers concentration were significantly higher in the H-Pb group: malondialdehyde (MDA) by 4%, and lipofuscin (LPS) by 9%. In the CEOAE results showed statistically significant differences between the L-Pb and H-Pb subgroups. Larger negative changes in otoemission amplitude were observed in H-Pb subgroup. All otoemission results showed a statistically significant negative correlation with age, time of work, MDA concentration, and with PbB. Selected CEOAE parameters showed a significant negative correlation with cadmium blood concentration (CdB), and a positive correlation with Ca and Zn. Conclusion: Elevated blood lead content in occupational exposure is associated with an increase in MDA and LPS concentration, which negatively correlates with CEOAE parameters. This suggests an important role of oxidative stress in the long-term deterioration of hearing. [ABSTRACT FROM AUTHOR]

Purpose: Otoacoustic emissions (OAE) are a common screening tool to evaluate cochlear function. Middle ear dysfunction has been shown to impact results of otoacoustic emission testing, but there are limited data on the effect of tympanostomy tubes on OAE. The purpose of this study was to determine whether tympanostomy tube placement significantly improved OAE. Methods: A retrospective review of charts was completed for patients younger than 18 years old who underwent tympanostomy tube placement from January 1, 2018 to September 1, 2023 and had preoperative and postoperative OAE testing within 6 months of surgery. The primary variable was presence of OAE preoperatively and postoperatively. Chi-square analysis and t test were used for statistical analysis. Results: A total of 212 ears were examined from 111 pediatric patients who underwent tympanostomy tube placement during the study period. Presence of OAE at 3000, 4000, and 5000 Hz were all noted to significantly increase following tympanostomy tube placement, with OAE presence increasing from approximately 27.8% of the sample preoperatively to 95.3% postoperatively at 3000 and 4000 Hz. Patients who noted improvement had a significantly higher proportion of type B tympanogram preoperatively, compared to a higher proportion of type A tympanogram noted in patients who did not note improvement. Conclusion: Tympanostomy tubes can significantly improve otoacoustic emissions in patients with middle ear dysfunction. [ABSTRACT FROM AUTHOR]

Background: Recent technological evolutions allow for the identification of hearing level (HL) in infants soon after birth. The goal of early hearing detection and intervention is to maximize linguistic and communication skills and literacy development for children who are deaf or hard of hearing. Infants whose HL has been confirmed before 6 months of age must be provided early intervention. Aims and Objectives: The aim of the study was to observe the changes in the otoacoustic emissions (OAE) and brainstem auditory evoked potential (BAEP) in infants with birth asphyxia (BA). Materials and Methods: The present study was a case– control study. A total of 50 cases of infants with BA and 50 normal-term infants were part of the study after obtaining informed consent as per the ICMR guidelines. A through clinical examination and otoscopy examination were done to rule out any conductive hearing loss. Then, OAE and BAEP were recorded to estimate the hearing loss and hearing threshold of infants. Results: BAEP waveform I, III, and V absolute latencies were significantly prolonged among BA infants than normal infants. The interpeak latency (IPL) of the right ear III-V was significantly increased in BA infants. However, III-V and I-V latencies though prolonged in BA infants, they are not statistically significant. No significant interaural difference was noted in absolute and IPLs of both BA and normal infants. No significant relationship existed between the mode of delivery and the degree of hearing loss in both ears. Significant association was observed between the degree of hearing loss and severity of BA (hypoxic-ischemic encephalopathy) in both ears. Conclusion: BAEP recording in BA infants is useful to identify the hearing impairment at the earliest. The implication of this research work will help in early detection of hearing impairment, so that speech and language developmental delay in the child can be prevented. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the current scoping review is to identify the studies reporting ototoxicity monitoring in individuals with head and neck cancer (HNC) undergoing radiation therapy and/or chemoradiation therapy across the world. The specific objectives were to identify and report the test protocol used, identify the most common timeline of follow-up, and identify barriers and facilitators influencing the implementation of the monitoring program. Method: A comprehensive search was conducted across six electronic databases, including PubMed, Embase, Web of Science, Scopus, Google Scholar, and ProQuest. The scoping review method adhered to relevant guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) and frameworks. The database search was carried out by two independent researchers, and studies were selected based on specific inclusion and exclusion criteria. Results: This scoping review identified 13 studies that fulfilled the inclusion criteria of this study. Only one study reported findings from the perspective of ototoxicity monitoring. Another study explicitly mentioned that ototoxicity monitoring was a standard of care in their hospital. Only one study reported using the relevant guidelines for monitoring ototoxicity. Specialized tests such as high-frequency audiometry, distortion product otoacoustic emissions, and vestibular tests were rarely used. Ototoxicity monitoring was influenced by awareness-related factors, technical factors, treatment-related factors, and organizational factors. Conclusions: Research on ototoxicity monitoring programs is in its early stages, highlighting the need for standardized practices and multidisciplinary collaboration to enhance health care services for HNC patients. A standardized approach, improved awareness, and the incorporation of patient perspectives are crucial to enhancing ototoxicity monitoring in HNC patients. [ABSTRACT FROM AUTHOR]

The cochlea, situated within the inner ear, is a spiral-shaped, liquid-filled organ responsible for hearing. The physiological significance of its shape remains uncertain. Previous research has scarcely addressed the occurrence of transverse flow within the cochlea, particularly in relation to its unique shape. This study aims to investigate the impact of the geometric features of the cochlea on fluid dynamics by characterizing transverse flow induced by harmonically oscillating axial flow in square ducts with curvature and torsion resembling human cochlear anatomy. We examined four geometries to investigate curvature and torsion effects on axial and transverse flow components. Twelve frequencies from 0.125 Hz to 256 Hz were studied, covering infrasound and low-frequency hearing, with mean inlet velocity amplitudes representing levels expected for normal conversation or louder situations. Our simulations show that torsion contributes significantly to transverse flow in unsteady conditions, and that its contribution increases with increasing oscillation frequency. Curvature alone has a small effect on transverse flow strength, which decreases rapidly with increasing frequency. Strikingly, the combined effect of curvature and torsion on transverse flow is greater than expected from a simple superposition of the two effects, especially when the relative contribution of curvature alone becomes negligible. These findings may be relevant to understanding physiological processes in the cochlea, including metabolite transport and wall shear stress. Further studies are needed to investigate possible implications for cochlear mechanics. [ABSTRACT FROM AUTHOR]

Objective: Describe the ear and hearing outcomes in Aboriginal infants in an Australian urban area. Design: Aboriginal infants enrolled in the Djaalinj Waakinj prospective cohort study had ear health screenings at ages 2-4, 6-8 and 12-18 months and audiological assessment at ∼12 months of age. Sociodemographic, environmental characteristics, otoscopy, otoacoustic emissions, tympanometry and visual reinforcement audiometry data were collected. Study Sample: 125 infants were enrolled in the study; 67 completed audiological assessment, 62, 54, and 58 of whom attended ear screenings at 2-4, 6-8 and 12-18 months. Results: Of the children that attended the audiological assessment, 36.5%, 50% and 64.3% of infants had otitis media (OM) at 2-4, 6-8 and 12-18 months. Using a 10 dB correction factor, 44.8% of infants had hearing loss (HL) (≥ 25 dB HL) at ∼ 12 months of age. More males (X2=5.4 (1df, p = 0.02)) and infants with OM at audiological assessment (X2=5.8 (1df, p = 0.02)) had HL. More infants that used a pacifier at 12-18 months of age had HL (X2=4.7 (1df, p = 0.03)). Conclusion: Aboriginal infants in an urban area have high rates of HL and OM, which requires early surveillance and timely treatment to reduce the medical and developmental impacts of OM and HL. [ABSTRACT FROM AUTHOR]

Background: Sensorial non-motor symptoms (NMSs) in Parkinson's disease (PD) still lack appropriate investigation in clinical practice. This study aimed to assess if and to what extent auditory dysfunction is associated with other NMSs in PD and its impact on patient's quality of life (QoL). Methods: We selected patients with idiopathic PD, without other concomitant neurological diseases, dementia, or diagnosis of any audiological/vestibular disease. Demographic and clinical data were collected. Patients underwent otoscopic examination, audiological testing with pure tone audiometry (PTA) and distortion product otoacoustic emissions (DPOAEs) and completed Non-Motor Symptoms Scale (NMSS) and Parkinson's Disease Questionnaires-39 (PDQ-39). ANCOVA and partial correlation analysis have been used for statistical analysis. Results: 60 patients were enrolled and completed PTA and DPOAEs. 32 patients with hearing impairment (HI), assessed by PTA, (hearing threshold ≥ 25 dB) showed similar disease duration, motor impairment, and staging, compared to patients without HI, but higher scores both in NMSS and in PDQ-39, except for cardiovascular (CV), gastrointestinal (GI), urogenital (U) and sexual function (SF) of NMSS. In addition, DPOAEs showed a significant correlation with higher scores both in NMSS and PDQ-39, except for CV, SF, GI, U and perceptual problem subdomains of NMSS. Conclusion: This study demonstrated that PD patients with HI have a greater burden of NMS and lower related QoL and functioning. Our results highlight the importance to reconsider HI as a NMS, in parallel with the others. HI evaluation, even in asymptomatic patients, may reveal a wider pathology with a worse QoL. [ABSTRACT FROM AUTHOR]

Wireless communication systems are facing challenges in maintaining high-quality speech transmission due to the growing amount of data being transmitted. Linear predictive coding (LPC) is by far the most popular speech coding technique. A well-known shortcoming of LPC-based methods is their sensitivity to noise. In recent research, slight performance improvement is observed for LPC-based speech coding system under noisy environments. In this paper, we propose a pre-processing speech enhancement technique based on deep neural networks (DNN) to improve speech coding quality in negative signal-to-noise ratio (SNR) conditions. Furthermore, this study emphasizes the significance of phase information and underscores the potential benefits of employing DNN-based pre-processing modules to improve speech coding quality. We evaluate our proposed method using two databases, NOIZEUS and Kannada, which contain a wide range of noise levels. Experimental results show that our method outperforms traditional LPC, as demonstrated by the speech quality metrics. [ABSTRACT FROM AUTHOR]

Input/output (I/O) functions of distortion-product otoacoustic emissions (DPOAEs) may contain sudden amplitude minima (notches) although they are measured in animals with a negligible reflection source. We measured DPOAEs in humans and analyzed the data by time-frequency filtering to decompose the nonlinear-distortion and coherent-reflection components of DPOAE. The presented I/O functions of the nonlinear-distortion component contain notches. We suggest that because these notches are present only in the nonlinear-distortion component, they result from destructive interference between distortion-product wavelets coming from the primary generation region. Simulations conducted with a nonlinear cochlear model showed qualitative similarities with the presented experimental results. [ABSTRACT FROM AUTHOR]

Background: No studies to date have compared audiologic characteristics in patients with continuous and intermittent tinnitus. The present study classified tinnitus patients into continuous and intermittent groups based on tinnitus duration and compared their audiologic characteristics. Methods: This study enrolled 604 patients with tinnitus from January 2019 to December 2022. Clinical manifestations, PTA results, the frequency and loudness of tinnitus, ABR, DPOAE, and TEOAE tests were compared in patients with continuous and intermittent tinnitus. Results: Of the 604 patients, 231 (38.2%) had continuous and 373 (61.8%) had intermittent tinnitus. There were no significant between-group differences in otologic symptoms, tinnitus onomatopoeia. PTA showed that hearing thresholds, except at 125 Hz, were significantly higher in patients with continuous rather than intermittent tinnitus. The loudness of tinnitus was significantly greater in patients with continuous rather than intermittent tinnitus. ABR tests showed that the absolute latency of wave V was significantly longer in continuous than in intermittent tinnitus. Signal-to-noise ratios on TEOAE tests were significantly lower in patients with continuous rather than intermittent tinnitus at all frequencies tested (1, 1.5, 2, 3, and 4 kHz). Response rates to sound stimuli at all frequencies, except for 1 kHz, were significantly lower on DPOAE tests in patients with continuous rather than intermittent tinnitus. Conclusions: Continuous tinnitus is more common in males, more persistent over time, and is associated with a higher rate of hearing loss. In contrast, intermittent tinnitus is more common in women, appears acutely, and is associated with a relatively lower rate of hearing loss. Based on the findings of the current paper, it seems that audiologic characteristics may differ between patients with continuous and intermittent tinnitus.

Objective: The aim of this study was to investigate whether ABO and Rhesus (Rh) blood type systems are associated with distortion product otoacoustic emission (DPOAE) and transient otoacoustic emission (TEOAE) amplitudes, with the hypothesis that blood types affect hearing thresholds. Methods: Seventy participants with normal hearing, aged 18-26 years, with normal tympanometry and otoscopic examination findings, were included in the study. TEOAE and DPOAE tests were conducted on all participants. Results: The Rh factor did not significantly affect the OAE results. It was found that the TEOAE amplitudes of blood type B at 1.4 kHz in the left ear were higher than those of blood types A and AB. The amplitude of AB blood was lower than that of O, A, and B blood types at 2 kHz. Conclusion: Our study results did not indicate a consistent pattern for a specific blood type, in contrast to previous findings. Additional research is required to investigate the potential correlation between hearing function and ABO and Rh blood types. [ABSTRACT FROM AUTHOR]

Background: No studies to date have compared audiologic characteristics in patients with continuous and intermittent tinnitus. The present study classified tinnitus patients into continuous and intermittent groups based on tinnitus duration and compared their audiologic characteristics. Methods: This study enrolled 604 patients with tinnitus from January 2019 to December 2022. Clinical manifestations, PTA results, the frequency and loudness of tinnitus, ABR, DPOAE, and TEOAE tests were compared in patients with continuous and intermittent tinnitus. Results: Of the 604 patients, 231 (38.2%) had continuous and 373 (61.8%) had intermittent tinnitus. There were no significant between-group differences in otologic symptoms, tinnitus onomatopoeia. PTA showed that hearing thresholds, except at 125 Hz, were significantly higher in patients with continuous rather than intermittent tinnitus. The loudness of tinnitus was significantly greater in patients with continuous rather than intermittent tinnitus. ABR tests showed that the absolute latency of wave V was significantly longer in continuous than in intermittent tinnitus. Signal-to-noise ratios on TEOAE tests were significantly lower in patients with continuous rather than intermittent tinnitus at all frequencies tested (1, 1.5, 2, 3, and 4 kHz). Response rates to sound stimuli at all frequencies, except for 1 kHz, were significantly lower on DPOAE tests in patients with continuous rather than intermittent tinnitus. Conclusions: Continuous tinnitus is more common in males, more persistent over time, and is associated with a higher rate of hearing loss. In contrast, intermittent tinnitus is more common in women, appears acutely, and is associated with a relatively lower rate of hearing loss. Based on the findings of the current paper, it seems that audiologic characteristics may differ between patients with continuous and intermittent tinnitus. [ABSTRACT FROM AUTHOR]

The study investigated the relationship between the strength of the medial olivocochlear reflex (measured via contralateral inhibition of otoacoustic emissions) and speech perception in noise (obtained from behavioural identification task) through meta-analyses. A systematic review and random-effects meta-analysis of studies investigating the relationship in neurotypical adults was performed. The systematic search (in PubMed, Scopus, Science Direct and Google Scholar databases) revealed 21 eligible studies, which were critically appraised using the NIH tool for Observational Cohort and Cross-Sectional Studies. Meta-analysis was performed on 17 studies (374 participants) with fair to good quality. The results revealed that the medial olivocochlear reflex accounts for less than 1% of the variations in speech perception in noise in neurotypical individuals. Sub-group analyses conducted to address a few methodological differences also revealed no discernible association between the two variables. The results reveal no modulatory effect of the medial olivocochlear reflex assessed using contralateral inhibition of otoacoustic emission on the ability to perceive speech in noise. However, more data utilising alternative measures of medial olivocochlear reflex strength is necessary before drawing any conclusions about the role of the medial olivocochlear bundle in speech perception in noise. [ABSTRACT FROM AUTHOR]

AbstractObjectivesDesignStudy SampleResultsConclusionThe objective of this systematic review was to assess the evidence about the prevalence of permanent hearing loss for children not identified from newborn hearing screening (NHS).Articles were grouped into three categories based on the methodological approach: (1) all participants received diagnostic testing, (2) otoacoustic emission (OAE) or pure tone screening was completed and those not passing were referred for a diagnostic test, and (3) data were retrieved from archival records. Study characteristics, prevalence, and contextual factors were synthesised and narratively described.30 peer-reviewed articles.Prevalence of permanent hearing loss per 1,000 children ranged from 0.32 to 77.87 (M = 7.30; SD = 16.87). Variations in the criteria for inclusion contributed to prevalence differences. Prevalence was higher when unilateral and milder degrees of hearing loss were included, and older children had higher prevalence (M = 13.71; SD = 23.21) than younger children (M = 1.57; SD = 0.86).There is scant research on prevalence of childhood hearing loss after NHS that utilised methods to accurately differentiate between permanent and temporary hearing loss. Rigorous research is needed on the prevalence of permanent childhood hearing loss to inform strategies for monitoring, identification, intervention, and management. [ABSTRACT FROM AUTHOR]

Although it is widely used, there is still no valid treatment for ototoxicity caused by the antineoplastic drug cisplatin. In this study, we aimed to investigate the efficacy of intratympanic resveratrol and intratympanic dexamethasone treatment in cisplatin-induced ototoxicity. We also compared intratympanic atosiban (oxytocin antagonist) and oxytocin in cisplatin ototoxicity. In this study, 30 rats (60 ears) were used by separating into 5 groups. Cisplatin, oxytocin, dexamethasone, atosiban and 0.9% NaCl were administered intraperitoneally to all groups separately. Auditory Brainstem Response and Distortion Product Otoacoustic Emission tests were performed on all groups before and 72 h after the procedure. Pre-treatment values were higher than post-treatment values in all groups (p < 0.001). There was no significant prolongation of the post-treatment Auditory Brainstem Response I-IV interval in the oxytocin and dexamethasone groups (p > 0.05). There was no significant decrease in the frequencies of 2832 and 4004 after treatment in the oxytocin and dexamethasone group compared to pre-treatment in Distortion Product Otoacoustic Emission. As a result, it has been shown that intratympanic oxytocin may be an option that can be used in the treatment, although it is not as effective as dexamethasone in preventing cisplatin ototoxicity. [ABSTRACT FROM AUTHOR]

Identifying auditory impairments early in newborns is essential to prevent developmental delays. Otoacoustic Emissions (OAE) screenings play a critical role in newborn hearing assessments. However, the ideal timing post-birth for these tests remains unclear. This study evaluates the efficacy of OAE screenings within the first five days after birth to determine the most effective timing. An observational study involved 1,013 full-term neonates at a tertiary care centre. These neonates underwent Transient Evoked Otoacoustic Emissions (TEOAE) screenings daily from Day 1 to Day 5, following WHO and JCIH guidelines. The study assessed pass rates, false positives, and false negatives, with follow-up screenings at one and three months for neonates with initial ambiguous results. The study found that screening efficiency significantly increased, with Day 1 pass rates at 8% (81 neonates) and 98% (992 neonates) by Day 5, marking a significant improvement in diagnostic accuracy (p < 0.001). False positive rates dropped from 92% on Day 1 to 2% by Day 5, and false negatives decreased to below 1%. Sensitivity and specificity reached their peak at 98% and 99.5%, respectively, on Day 5. Our study findings advocate for adjusting neonatal hearing screening protocols to include OAE tests on the fifth day post-birth, optimizing clinical efficacy through enhanced diagnostic accuracy and reducing the logistical and emotional burdens on families and healthcare providers. [ABSTRACT FROM AUTHOR]

Objective: Exploring the auditory and vestibular manifestations associated with chronic kidney disease (CKD) has been growing in recent years. Understanding these complaints in CKD patients is crucial for comprehensive patient care. This review aimed to investigate the audiological findings and profiles across various stages of CKD and guide for informed decision-making in their management. Methods: Relevant articles from PubMed, ScienceDirect, EBSCO Medline, SCOPUS, Google Scholar, and Clinical Key were identified for review. The selected articles were published from 2008 to 2023 and written in English language. A total of 41 articles on auditory and vestibular assessments in CKD were eligible for review. Results: Pure tone audiometry (PTA), immittance audiometry (IA) and otoacoustic emissions (OAEs) were the most commonly employed hearing tests respectively, with a higher frequency of utilization in hemodialysis cases compared to non-hemodialysis ones. Also, vestibular evoked myogenic potentials (VEMPs) emerged as the most popular vestibular test among hemodialysis patients while questionnaires were frequently employed in CKD patients. Moreover, our analysis suggests a potential association between the duration of hemodialysis and the development of tinnitus and vertigo. Abnormalities were also observed in auditory brainstem response (ABR), speech audiometry, central auditory processing tests and videonystagmography (VNG) assessment in hemodialysis and non-hemodialysis patients. Conclusion: CKD patients, particularly those undergoing hemodialysis, face a higher risk of hearing loss, tinnitus, and vestibular complaints. Performing otoacoustic emissions and vestibular-evoked myogenic potentials along with PTA on CKD patients, regardless of the disease stage is recommended to more effective management of audiovestibular complaints in these population. [ABSTRACT FROM AUTHOR]

Objective: To retrospectively analyze clinical features in adolescent Menière's disease (MD). Methods: The medical records of adolescents with MD (11–17 years old) from May 2014 to March 2023 in Shandong Provincial ENT Hospital were retrospectively analyzed, including clinical features, a battery of auditory and vestibular function tests, sensory organization test, and imaging assessments. Patients with recurrent vertigo of childhood (RVC) were as controls. Results: Compared with RVC, adolescent MD showed higher pure tone average threshold (p <.001), lower speech discrimination score (p =.014), and lower otoacoustic emission pass rates (p =.005). Adolescents with MD exhibited significant reduction in equilibrium score (Conditions 1, 5, and 6; p1 =.035; p5 =.033; p6 =.003), composite sensory score (p =.014), and vestibular sensory score (p =.029). Adolescents with bilateral MD exhibited worse performance in equilibrium score and strategy score compared to adolescents with unilateral MD. For the affected ear, the more severe endolymphatic hydrops detected by gadolinium‐enhanced magnetic resonance imaging, the higher the auditory brainstem response threshold (r =.850, p =.007), and the lower the otoacoustic emission pass rate (r = −.976, p <.001). Conclusion: Adolescent MD has similar vestibular information inputs with that of RVC, but the ability for the nerve center to use these clues to maintain balance is worse in adolescents with MD. There were potential differences in vestibular weights in adolescents with unilateral and bilateral MD, also potential effects on vision and proprioception. Level of Evidence: Level 4. [ABSTRACT FROM AUTHOR]

A study published in Clinical & Translational Medicine suggests that the antiviral drug oseltamivir (Tamiflu) may have potential as a treatment for hearing loss. The researchers found that oseltamivir protected against hair cell loss in mouse cochlear explants caused by the chemotherapy drug cisplatin, without affecting cisplatin's ability to kill tumors. In mouse models, oseltamivir also protected against cisplatin-induced hearing loss and outer hair cell loss. Furthermore, oral oseltamivir therapy showed promise in protecting against noise-induced hearing loss. The study suggests that oseltamivir could be a promising candidate for treating hearing loss caused by chemotherapy and noise exposure. [Extracted from the article]

A fast numerical time-domain solution for a one-dimensional cochlear transmission-line model was proposed for real-time applications. In this approach, the three-dimensional solver developed by Murakami [J. Acoust. Soc. Am. 150(4), 2589–2599 (2021)] was modified to develop a solution for the one-dimensional model. This development allows the solution to accurately and quickly calculate cochlear responses. The present solution can solve the model in real-time under coarse grid conditions. However, under fine-grid conditions, the computation time is significantly longer than the duration of the signal. Nevertheless, calculations can be performed under the fine grid condition, which previously required much computation time. This fact is essential to applications. [ABSTRACT FROM AUTHOR]

Purpose: Tone-pip-evoked otoacoustic emissions (PEOAEs) are transient-evoked otoacoustic emissions (OAEs) that are hypothesized to originate from reflection of energy near the best-frequency (BF) cochlear place of the stimulus frequency. However, individual PEOAEs have energy with a wide range of delays. We sought to determine whether some PEOAE energy is consistent with having been generated far from BF. Methods: PEOAEs from 35 and 47 dB SPL tone pips were obtained by removing pip-stimulus energy by subtracting the ear-canal sound pressure from scaled-down 59 dB SPL tone pips (which evoke relatively small OAEs). PEOAE delays were measured at each peak in the PEOAE absolute-value waveforms. While measuring PEOAEs and auditory-nerve compound action potentials (CAPs), amplification was blocked sequentially from apex to base by cochlear salicylate perfusion. The perfusion time when a CAP was reduced identified when the perfusion reached the tone-pip BF place. The perfusion times when each PEOAE peak was reduced identified where along the cochlea it received cochlear amplification. PEOAEs and CAPs were measured simultaneously using one pip frequency in each ear (1.4 to 4 kHz across 16 ears). Results: Most PEOAE peaks received amplification primarily between the BF place and 1–2 octaves basal of the BF place. PEOAE peaks with short delays received amplification basal of BF place. PEOAE peaks with longer delays sometimes received amplification apical of BF place, consistent with previous stimulus-frequency-OAE results. Conclusion: PEOAEs provide information about cochlear amplification primarily within ~ 1.5 octave of the tone-pip BF place, not about regions > 3 octaves basal of BF. [ABSTRACT FROM AUTHOR]

Otoacoustic emissions (OAEs) are generated in the cochlea and recorded in the ear canal either as a time domain waveform or as a collection of complex responses to tones in the frequency domain (Probst et al. J Account Soc Am 89:2027–2067, 1991). They are typically represented either in their original acquisition domain or in its Fourier-conjugated domain. Round-trip excursions to the conjugated domain are often used to perform filtering operations in the computationally simplest way, exploiting the convolution theorem. OAE signals consist of the superposition of backward waves generated in different cochlear regions by different generation mechanisms, over a wide frequency range. The cochlear scaling symmetry (cochlear physics is the same at all frequency scales), which approximately holds in the human cochlea, leaves its fingerprints in the mathematical properties of OAE signals. According to a generally accepted taxonomy (Sher and Guinan Jr, J Acoust Soc Am 105:782–798, 1999), OAEs are generated either by wave-fixed sources, moving with frequency according with the cochlear scaling (as in nonlinear distortion) or by place-fixed sources (as in coherent reflection by roughness). If scaling symmetry holds, the two generation mechanisms yield OAEs with different phase gradient delay: almost null for wave-fixed sources, and long (and scaling as 1/f) for place-fixed sources. Thus, the most effective representation of OAE signals is often that respecting the cochlear scale-invariance, such as the time-frequency domain representation provided by the wavelet transform. In the time-frequency domain, the elaborate spectra or waveforms yielded by the superposition of OAE components from different generation mechanisms assume a much clearer 2-D pattern, with each component localized in a specific and predictable region. The wavelet representation of OAE signals is optimal both for visualization purposes and for designing filters that effectively separate different OAE components, improving both the specificity and the sensitivity of OAE-based applications. Indeed, different OAE components have different physiological meanings, and filtering dramatically improves the signal-to-noise ratio. [ABSTRACT FROM AUTHOR]

Across the wide range of land vertebrate species, spontaneous otoacoustic emissions (SOAE) are common, but not always found. The reasons for the differences between species of the various groups in their emission patterns are often not well understood, particularly within mammals. This review examines the question as to what determines in mammals whether SOAE are emitted or not, and suggests that the coupling between hair-cell regions diminishes when the space constant of frequency distribution becomes larger. The reduced coupling is assumed to result in a greater likelihood of SOAE being emitted. [ABSTRACT FROM AUTHOR]

Purpose: Age-related hearing loss is the most common form of permanent hearing loss that is associated with various health traits, including Alzheimer's disease, cognitive decline, and depression. The present study aims to identify genetic comorbidities of age-related hearing loss. Past genome-wide association studies identified multiple genomic loci involved in common adult-onset health traits. Polygenic risk scores (PRS) could summarize the polygenic inheritance and quantify the genetic susceptibility of complex traits independent of trait expression. The present study conducted a PRS-based association analysis of age-related hearing difficulty in the UK Biobank sample (N = 425,240), followed by a replication analysis using hearing thresholds (HTs) and distortion-product otoacoustic emissions (DPOAEs) in 242 young adults with self-reported normal hearing. We hypothesized that young adults with genetic comorbidities associated with age-related hearing difficulty would exhibit subclinical decline in HTs and DPOAEs in both ears. Methods: A total of 111,243 participants reported age-related hearing difficulty in the UK Biobank sample (> 40 years). The PRS models were derived from the polygenic risk score catalog to obtain 2627 PRS predictors across the health spectrum. HTs (0.25–16 kHz) and DPOAEs (1–16 kHz, L1/L2 = 65/55 dB SPL, F2/F1 = 1.22) were measured on 242 young adults. Saliva-derived DNA samples were subjected to low-pass whole genome sequencing, followed by genome-wide imputation and PRS calculation. The logistic regression analyses were performed to identify PRS predictors of age-related hearing difficulty in the UK Biobank cohort. The linear mixed model analyses were performed to identify PRS predictors of HTs and DPOAEs. Results: The PRS-based association analysis identified 977 PRS predictors across the health spectrum associated with age-related hearing difficulty. Hearing difficulty and hearing aid use PRS predictors revealed the strongest association with the age-related hearing difficulty phenotype. Youth with a higher genetic predisposition to hearing difficulty revealed a subclinical elevation in HTs and a decline in DPOAEs in both ears. PRS predictors associated with age-related hearing difficulty were enriched for mental health, lifestyle, metabolic, sleep, reproductive, digestive, respiratory, hematopoietic, and immune traits. Fifty PRS predictors belonging to various trait categories were replicated for HTs and DPOAEs in both ears. Conclusion: The study identified genetic comorbidities associated with age-related hearing loss across the health spectrum. Youth with a high genetic predisposition to age-related hearing difficulty and other related complex traits could exhibit sub-clinical decline in HTs and DPOAEs decades before clinically meaningful age-related hearing loss is observed. We posit that effective communication of genetic risk, promoting a healthy lifestyle, and reducing exposure to environmental risk factors at younger ages could help prevent or delay the onset of age-related hearing difficulty at older ages. [ABSTRACT FROM AUTHOR]

When David Kemp discovered "spontaneous ear noise" in 1978, it opened up a whole new perspective on how the cochlea works. The continuous tonal sound emerging from most healthy human ears, now called spontaneous otoacoustic emissions or SOAEs, was an unmistakable sign that our hearing organ must be considered an active detector, not just a passive microphone, just as Thomas Gold had speculated some 30 years earlier. Clearly, something is oscillating as a byproduct of that sensitive inbuilt detector, but what exactly is it? Here, we give a chronological account of efforts to model SOAEs as some form of oscillator, and at intervals, we illustrate key concepts with numerical simulations. We find that after many decades there is still no consensus, and the debate extends to whether the oscillator is local, confined to discrete local sources on the basilar membrane, or global, in which an assembly of micro-mechanical elements and basilar membrane sections, coupled by inner ear fluid, interact over a wide region. It is also undecided whether the cochlear oscillator is best described in terms of the well-known Van der Pol oscillator or the less familiar Duffing or Hopf oscillators. We find that irregularities play a key role in generating the emissions. This paper is not a systematic review of SOAEs and their properties but more a historical survey of the way in which various oscillator configurations have been applied to modelling human ears. The conclusion is that the difference between the local and global approaches is not clear-cut, and they are probably not mutually exclusive concepts. Nevertheless, when one sees how closely human SOAEs can be matched to certain arrangements of oscillators, Gold would no doubt say we are on the right track. [ABSTRACT FROM AUTHOR]