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BMC Neuroscience Dec 2022Hearing loss is a major health problem and psychological burden in humans. Mouse models offer a possibility to elucidate genes involved in the underlying developmental...
Hearing loss is a major health problem and psychological burden in humans. Mouse models offer a possibility to elucidate genes involved in the underlying developmental and pathophysiological mechanisms of hearing impairment. To this end, large-scale mouse phenotyping programs include auditory phenotyping of single-gene knockout mouse lines. Using the auditory brainstem response (ABR) procedure, the German Mouse Clinic and similar facilities worldwide have produced large, uniform data sets of averaged ABR raw data of mutant and wildtype mice. In the course of standard ABR analysis, hearing thresholds are assessed visually by trained staff from series of signal curves of increasing sound pressure level. This is time-consuming and prone to be biased by the reader as well as the graphical display quality and scale.In an attempt to reduce workload and improve quality and reproducibility, we developed and compared two methods for automated hearing threshold identification from averaged ABR raw data: a supervised approach involving two combined neural networks trained on human-generated labels and a self-supervised approach, which exploits the signal power spectrum and combines random forest sound level estimation with a piece-wise curve fitting algorithm for threshold finding.We show that both models work well and are suitable for fast, reliable, and unbiased hearing threshold detection and quality control. In a high-throughput mouse phenotyping environment, both methods perform well as part of an automated end-to-end screening pipeline to detect candidate genes for hearing involvement. Code for both models as well as data used for this work are freely available.
Topics: Humans; Animals; Mice; Evoked Potentials, Auditory, Brain Stem; Reproducibility of Results; Auditory Threshold; Hearing; Deafness; Acoustic Stimulation
PubMed: 36575380
DOI: 10.1186/s12868-022-00758-0 -
Temporary and Permanent Noise-induced Threshold Shifts: A Review of Basic and Clinical Observations.Otology & Neurotology : Official... Sep 2016To review basic and clinical findings relevant to defining temporary (TTS) and permanent (PTS) threshold shifts and their sequelae. (Review)
Review
OBJECTIVE
To review basic and clinical findings relevant to defining temporary (TTS) and permanent (PTS) threshold shifts and their sequelae.
DATA SOURCES
Relevant scientific literature and government definitions were broadly reviewed.
DATA SYNTHESIS
The definitions and characteristics of TTS and PTS were assessed and recent advances that expand our knowledge of the extent, nature, and consequences of noise-induced hearing loss were reviewed.
CONCLUSION
Exposure to intense sound can produce TTS, acute changes in hearing sensitivity that recover over time, or PTS, a loss that does not recover to preexposure levels. In general, a threshold shift ≥10 dB at 2, 3, and 4 kHz is required for reporting purposes in human studies. The high-frequency regions of the cochlea are most sensitive to noise damage. Resonance of the ear canal also results in a frequency region of high-noise sensitivity at 4 to 6 kHz. A primary noise target is the cochlear hair cell. Although the mechanisms that underlie such hair cell damage remain unclear, there is evidence to support a role for reactive oxygen species, stress pathway signaling, and apoptosis. Another target is the synapse between the hair cell and the primary afferent neurons. Large numbers of these synapses and their neurons can be lost after noise, even though hearing thresholds may return to normal. This affects auditory processing and detection of signals in noise. The consequences of TTS and PTS include significant deficits in communication that can impact performance of military duties or obtaining/retaining civilian employment. Tinnitus and exacerbation of posttraumatic stress disorder are also potential sequelae.
Topics: Animals; Auditory Threshold; Hearing Loss, Noise-Induced; Humans; Noise
PubMed: 27518135
DOI: 10.1097/MAO.0000000000001071 -
Neuroscience May 2019Noise-induced hidden hearing loss (NIHHL) has attracted great attention in hearing research and clinical audiology since the discovery of significant noise-induced... (Review)
Review
Noise-induced hidden hearing loss (NIHHL) has attracted great attention in hearing research and clinical audiology since the discovery of significant noise-induced synaptic damage in the absence of permanent threshold shifts (PTS) in animal models. Although the extant evidence for this damage is based on animal models, NIHHL likely occurs in humans as well. This review focuses on three issues concerning NIHHL that are somewhat controversial: (1) whether disrupted synapses can be re-established; (2) whether synaptic damage and repair are responsible for the initial temporal threshold shifts (TTS) and subsequent recovery; and (3) the relationship between the synaptic damage and repair processes and neural coding deficits. We conclude that, after a single, brief noise exposure, (1) the damaged and the totally destroyed synapses can be partially repaired, but the repaired synapses are functionally abnormal; (2) While deficits are observed in some aspects of neural responses related to temporal and intensity coding in the auditory nerve, we did not find strong evidence for hypothesized coding-in-noise deficits; (3) the sensitivity and the usefulness of the envelope following responses to amplitude modulation signals in detecting cochlear synaptopathy is questionable.
Topics: Animals; Auditory Perception; Auditory Threshold; Evoked Potentials, Auditory, Brain Stem; Hearing Loss, Noise-Induced; Humans; Otoacoustic Emissions, Spontaneous; Synapses
PubMed: 30267832
DOI: 10.1016/j.neuroscience.2018.09.026 -
Fa Yi Xue Za Zhi Aug 2023The qualitative, quantitative, and localization analysis of hearing loss is one of the important contents of forensic clinical research and identification. Pure-tone... (Review)
Review
The qualitative, quantitative, and localization analysis of hearing loss is one of the important contents of forensic clinical research and identification. Pure-tone audiometry is the "gold standard" for hearing loss assessment, but it is affected by the subjective cooperation of the assessed person. Due to the complexity of the auditory pathway and the diversity of hearing loss, the assessment of hearing loss requires the combination of various subjective and objective audiometric techniques, along with comprehensive evaluation based on the case situation, clinical symptoms, and other examinations to ensure the scientificity, accuracy and reliability of forensic hearing impairment assessment. Objective audiometry includes acoustic impedance, otoacoustic emission, and various auditory evoked potentials. The frequency-specific auditory brainstem response (ABR), 40 Hz auditory event related potential, and auditory steady-state response are commonly used for objective hearing threshold assessment. The combined application of acoustic impedance, otoacoustic emission and ABR can be used to locate hearing loss and determine whether it is located in the middle ear, cochlea, or posterior cochlea. This article reviews the application value of objective audiometry techniques in hearing threshold assessment and hearing loss localization, aiming to provide reference for forensic identification of hearing loss.
Topics: Humans; Reproducibility of Results; Auditory Threshold; Evoked Potentials, Auditory, Brain Stem; Hearing Loss; Audiometry, Pure-Tone; Clinical Medicine
PubMed: 37859474
DOI: 10.12116/j.issn.1004-5619.2023.230406 -
Ear and Hearing 2022Despite a diagnosis of normal hearing, many people experience hearing disability (HD) in their everyday lives. This study assessed the ability of a number of demographic...
OBJECTIVES
Despite a diagnosis of normal hearing, many people experience hearing disability (HD) in their everyday lives. This study assessed the ability of a number of demographic and auditory variables to explain and predict self-reported HD in people regarded as audiologically healthy via audiometric thresholds.
DESIGN
One-hundred eleven adults (ages 19 to 74) with clinically normal hearing (i.e., audiometric thresholds ≤25 dB HL at all octave and interoctave frequencies between 0.25 and 8 kHz and bilaterally symmetric hearing) were asked to complete the 12-item version of the Speech, Spatial, and Qualities of Hearing Scale (SSQ12) as a measure of self-reported HD. Patient history and a number of standard and expanded measures of hearing were assessed in a multivariate regression analysis to predict SSQ12 score. Patient history included age, sex, history of noise exposure, and tinnitus. Hearing-related measures included audiometry at standard and extended high frequencies, word recognition, otoacoustic emissions, auditory brainstem response, the Montreal Cognitive Assessment, and FM detection threshold.
RESULTS
History of impulse noise exposure, speech-intelligibility index, and FM detection threshold accurately predicted SSQ12 and were able to account for 40% of the SSQ12 score. These three measures were also able to predict whether participants self-reported HD with a sensitivity of 89% and specificity of 86%.
CONCLUSIONS
Although participant audiometric thresholds were within normal limits, higher thresholds, history of impulse noise exposure, and FM detection predicted self-reported HD.
Topics: Adult; Aged; Audiometry; Audiometry, Pure-Tone; Auditory Threshold; Hearing; Humans; Middle Aged; Otoacoustic Emissions, Spontaneous; Self Report; Young Adult
PubMed: 34759207
DOI: 10.1097/AUD.0000000000001161 -
Hearing Research Mar 2024Hearing loss affects approximately 18% of the population worldwide. Hearing difficulties in noisy environments without accompanying audiometric threshold shifts likely... (Review)
Review
Hearing loss affects approximately 18% of the population worldwide. Hearing difficulties in noisy environments without accompanying audiometric threshold shifts likely affect an even larger percentage of the global population. One of the potential causes of hidden hearing loss is cochlear synaptopathy, the loss of synapses between inner hair cells (IHC) and auditory nerve fibers (ANF). These synapses are the most vulnerable structures in the cochlea to noise exposure or aging. The loss of synapses causes auditory deafferentation, i.e., the loss of auditory afferent information, whose downstream effect is the loss of information that is sent to higher-order auditory processing stages. Understanding the physiological and perceptual effects of this early auditory deafferentation might inform interventions to prevent later, more severe hearing loss. In the past decade, a large body of work has been devoted to better understand hidden hearing loss, including the causes of hidden hearing loss, their corresponding impact on the auditory pathway, and the use of auditory physiological measures for clinical diagnosis of auditory deafferentation. This review synthesizes the findings from studies in humans and animals to answer some of the key questions in the field, and it points to gaps in knowledge that warrant more investigation. Specifically, recent studies suggest that some electrophysiological measures have the potential to function as indicators of hidden hearing loss in humans, but more research is needed for these measures to be included as part of a clinical test battery.
Topics: Animals; Humans; Hearing Loss, Noise-Induced; Noise; Auditory Threshold; Hearing Loss, Hidden; Auditory Perception; Cochlea; Synapses; Evoked Potentials, Auditory, Brain Stem
PubMed: 38335624
DOI: 10.1016/j.heares.2024.108967 -
Brazilian Journal of Otorhinolaryngology 2011Accurate information about type, degree, and configuration of hearing loss are necessary for successful audiological early interventions. Auditory brainstem response... (Comparative Study)
Comparative Study
UNLABELLED
Accurate information about type, degree, and configuration of hearing loss are necessary for successful audiological early interventions. Auditory brainstem response with tone burst stimuli (TB ABR) and auditory steady-state response (ASSR) exams provide this information.
AIM
To analyze the clinical applicability of TB ABR and ASSR at 2 kHz in infants, comparing responses in full-term and premature neonates.
MATERIAL AND METHOD
The study was cross-sectional, clinical and experimental. Subjects consisted of 17 premature infants and 19 full-term infants. TB ABR and ASSR exams at 2000 Hz were done during natural sleep.
RESULTS
The electrophysiological minimum response obtained with TB ABR was 32.4 dBnHL (52.4 dBSPL); the ASSR minimum was 13.8 dBHL (26.4 dBSPL). The exams required 21.1 min and 22 min, respectively. Premature and full-term infant responses showed no statistically significant differences, except for auditory steady-state response duration.
CONCLUSIONS
Both exams have clinical applicability at 2 kHz in infants, with 20 min of duration, on average. In general, there are no differences between premature and full-term individuals.
Topics: Acoustic Stimulation; Audiometry, Evoked Response; Auditory Threshold; Cross-Sectional Studies; Evoked Potentials, Auditory, Brain Stem; Female; Humans; Infant, Newborn; Infant, Premature; Male
PubMed: 22030972
DOI: 10.1590/s1808-86942011000500015 -
Biomedical Engineering Online Jan 2021An electrical potential not previously reported-electrical cochlear response (ECR)-observed only in implanted patients is described. Its amplitude and growth slope are a...
BACKGROUND
An electrical potential not previously reported-electrical cochlear response (ECR)-observed only in implanted patients is described. Its amplitude and growth slope are a measurement of the stimulation achieved by a tone pip on the auditory nerve. The stimulation and recording system constructed for this purpose, the features of this potential obtained in a group of 43 children, and its possible clinical use are described. The ECR is obtained by averaging the EEG epochs acquired each time the cochlear implant (CI) processes a tone pip of known frequency and intensity when the patient is sleeping and using the CI in everyday mode. The ECR is sensitive to tone pip intensity level, microphone sensitivity, sound processor gain, dynamic range of electrical current, and responsiveness to electrical current of the auditory nerve portion involved with the electrode under test. It allows individual evaluation of intracochlear electrodes by choosing, one at the time, the central frequency of the electrode as the test tone pip frequency, so the ECR measurement due to a variable intensity tone pip allows to establish the suitability of the dynamic range of the electrode current.
RESULTS
There is a difference in ECR measurements when patients are grouped based on their auditory behavior. The ECR slope and amplitude for the Sensitive group is 0.2 μV/dB and 10 μV at 50 dB compared with 0.04 μV/dB and 3 μV at 50dB for the Inconsistent group. The clinical cases show that adjusting the dynamic range of current based on the ECR improved the patient's auditory behavior.
CONCLUSIONS
ECR can be recorded regardless of the artifact due to the electromyographic activity of the patient and the functioning of the CI. Its amplitude and growth slope versus the intensity of the stimulus differs between electrodes. The relationship between minimum ECR detection intensity level and auditory threshold suggests the possibility of estimating patient auditory thresholds this way. ECR does not depend on the subject's age, cooperation, or health status. It can be obtained at any time after implant surgery and the test procedure is the same regardless of device manufacturer.
Topics: Auditory Threshold; Child; Cochlear Implants; Cochlear Nerve; Evoked Potentials, Auditory; Female; Humans; Male
PubMed: 33446195
DOI: 10.1186/s12938-020-00844-6 -
American Journal of Otolaryngology 2022This study compared distortion product otoacoustic emissions (DPOAEs) and click-evoked auditory brainstem responses (ABRs) recorded from infants whose mother had...
BACKGROUND
This study compared distortion product otoacoustic emissions (DPOAEs) and click-evoked auditory brainstem responses (ABRs) recorded from infants whose mother had Covid-19 during pregnancy (Covid-19 group) to infants whose mother did not have Covid-19 (Control group) during pregnancy.
METHODS
This study retrospectively examined records of infants in the Covid-19 group (n = 15) and control group (n = 46) who had distortion product otoacoustic emissions (DPOAEs) and click-evoked auditory brainstem responses (ABRs) recorded as part of their clinical assessment. DPOAE amplitudes, absolute latencies (I, III, and V), and I-V interpeak intervals were examined.
RESULTS
DPOAE amplitudes were similar between the Covid-19 group and the control group. The absolute latency of wave I was similar between groups. But absolute latencies III and V and I-V interpeak intervals of the Covid-19 group were significantly prolonged compared to the control group.
CONCLUSION
Covid-19 infection and its complications during pregnancy may not affect the cochlear function but may affect the functioning of the auditory brainstem.
Topics: Auditory Threshold; COVID-19; Evoked Potentials, Auditory, Brain Stem; Female; Humans; Infant; Otoacoustic Emissions, Spontaneous; Pregnancy; Retrospective Studies
PubMed: 35533437
DOI: 10.1016/j.amjoto.2022.103484 -
Trends in Hearing 2023Bone conduction (BC) stimulation has mainly been used for clinical hearing assessment and hearing aids where stimulation is applied at the mastoid behind the ear....
Bone conduction (BC) stimulation has mainly been used for clinical hearing assessment and hearing aids where stimulation is applied at the mastoid behind the ear. Recently, BC has become popular for communication headsets where the stimulation position often is close to the anterior part of the ear canal opening. The BC sound transmission for this stimulation position is here investigated in 21 participants by ear canal sound pressure measurements and hearing threshold assessment as well as simulations in the LiUHead. The results indicated that a stimulation position close to the ear canal opening improves the sensitivity for BC sound by around 20 dB but by up to 40 dB at some frequencies. The transcranial transmission ranges typically between -40 and -25 dB. This decreased transcranial transmission facilitates saliency of binaural cues and implies that BC headsets are suitable for virtual and augmented reality applications. The findings suggest that with BC stimulation close to the ear canal opening, the sound pressure in the ear canal dominates the perception of BC sound. With this stimulation, the ear canal pathway was estimated to be around 25 dB greater than other contributors, like skull bone vibrations, for hearing BC sound in a healthy ear. This increased contribution from the ear canal sound pressure to BC hearing means that a position close to the ear canal is not appropriate for clinical use since, in such case, a conductive hearing loss affects BC and air conduction thresholds by a similar amount.
Topics: Humans; Bone Conduction; Acoustic Stimulation; Auditory Threshold; Hearing; Sound
PubMed: 37083055
DOI: 10.1177/23312165231168741