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Panario J, Bester C, O'Leary S. Predicting Postoperative Speech Perception and Audiometric Thresholds Using Intracochlear Electrocochleography in Cochlear Implant Recipients. Ear Hear 2024; 45:1173-1190. [PMID: 38816899 DOI: 10.1097/aud.0000000000001506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
OBJECTIVES Electrocochleography (ECochG) appears to offer the most accurate prediction of post-cochlear implant hearing outcomes. This may be related to its capacity to interrogate the health of underlying cochlear tissue. The four major components of ECochG (cochlear microphonic [CM], summating potential [SP], compound action potential [CAP], and auditory nerve neurophonic [ANN]) are generated by different cochlear tissue components. Analyzing characteristics of these components can reveal the state of hair and neural cell in a cochlea. There is limited evidence on the characteristics of intracochlear (IC) ECochG recordings measured across the array postinsertion but compared with extracochlear recordings has better signal to noise ratio and spatial specificity. The present study aimed to examine the relationship between ECochG components recorded from an IC approach and postoperative speech perception or audiometric thresholds. DESIGN In 113 human subjects, responses to 500 Hz tone bursts were recorded at 11 IC electrodes across a 22-electrode cochlear implant array immediately following insertion. Responses to condensation and rarefaction stimuli were then subtracted from one another to emphasize the CM and added to one another to emphasize the SP, ANN, and CAP. Maximum amplitudes and extracochlear electrode locations were recorded for each of these ECochG components. These were added stepwise to a multi-factor generalized additive model to develop a best-fit model predictive model for pure-tone audiometric thresholds (PTA) and speech perception scores (speech recognition threshold [SRT] and consonant-vowel-consonant phoneme [CVC-P]) at 3- and 12-month postoperative timepoints. This best-fit model was tested against a generalized additive model using clinical factors alone (preoperative score, age, and gender) as a null model proxy. RESULTS ECochG-factor models were superior to clinical factor models in predicting postoperative PTA, CVC-P, and SRT outcomes at both timepoints. Clinical factor models explained a moderate amount of PTA variance ( r2 = 45.9% at 3-month, 31.8% at 12-month, both p < 0.001) and smaller variances of CVC-P and SRT ( r2 range = 6 to 13.7%, p = 0.008 to 0.113). Age was not a significant predictive factor. ECochG models explained more variance at the 12-month timepoint ( r2 for PTA = 52.9%, CVC-P = 39.6%, SRT = 36.4%) compared with the 3-month one timepoint ( r2 for PTA = 49.4%, CVC-P = 26.5%, SRT = 22.3%). The ECochG model was based on three factors: maximum SP deflection amplitude, and electrode position of CM and SP peaks. Adding neural (ANN and/or CAP) factors to the model did not improve variance explanation. Large negative SP deflection was associated with poorer outcomes and a large positive SP deflection with better postoperative outcomes. Mid-array peaks of SP and CM were both associated with poorer outcomes. CONCLUSIONS Postinsertion IC-ECochG recordings across the array can explain a moderate amount of postoperative speech perception and audiometric thresholds. Maximum SP deflection and its location across the array appear to have a significant predictive value which may reflect the underlying state of cochlear health.
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Affiliation(s)
- Jared Panario
- Department Otolaryngology, University of Melbourne, Melbourne, Victoria, Australia
| | - Christofer Bester
- Department Otolaryngology, University of Melbourne, Melbourne, Victoria, Australia
| | - Stephen O'Leary
- Department Otolaryngology, University of Melbourne, Melbourne, Victoria, Australia
- Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
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2
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Ji L, Borges BC, Martel DT, Wu C, Liberman MC, Shore SE, Corfas G. From hidden hearing loss to supranormal auditory processing by neurotrophin 3-mediated modulation of inner hair cell synapse density. PLoS Biol 2024; 22:e3002665. [PMID: 38935589 PMCID: PMC11210788 DOI: 10.1371/journal.pbio.3002665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 05/07/2024] [Indexed: 06/29/2024] Open
Abstract
Loss of synapses between spiral ganglion neurons and inner hair cells (IHC synaptopathy) leads to an auditory neuropathy called hidden hearing loss (HHL) characterized by normal auditory thresholds but reduced amplitude of sound-evoked auditory potentials. It has been proposed that synaptopathy and HHL result in poor performance in challenging hearing tasks despite a normal audiogram. However, this has only been tested in animals after exposure to noise or ototoxic drugs, which can cause deficits beyond synaptopathy. Furthermore, the impact of supernumerary synapses on auditory processing has not been evaluated. Here, we studied mice in which IHC synapse counts were increased or decreased by altering neurotrophin 3 (Ntf3) expression in IHC supporting cells. As we previously showed, postnatal Ntf3 knockdown or overexpression reduces or increases, respectively, IHC synapse density and suprathreshold amplitude of sound-evoked auditory potentials without changing cochlear thresholds. We now show that IHC synapse density does not influence the magnitude of the acoustic startle reflex or its prepulse inhibition. In contrast, gap-prepulse inhibition, a behavioral test for auditory temporal processing, is reduced or enhanced according to Ntf3 expression levels. These results indicate that IHC synaptopathy causes temporal processing deficits predicted in HHL. Furthermore, the improvement in temporal acuity achieved by increasing Ntf3 expression and synapse density suggests a therapeutic strategy for improving hearing in noise for individuals with synaptopathy of various etiologies.
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Affiliation(s)
- Lingchao Ji
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Beatriz C. Borges
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - David T. Martel
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Calvin Wu
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - M. Charles Liberman
- Mass Eye and Ear Infirmary and Harvard Medical School. Boston, Massachusetts, United States of America
| | - Susan E. Shore
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
- Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, United States of America
- Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Gabriel Corfas
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
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Liu J, Stohl J, Overath T. Hidden hearing loss: Fifteen years at a glance. Hear Res 2024; 443:108967. [PMID: 38335624 DOI: 10.1016/j.heares.2024.108967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 01/15/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024]
Abstract
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.
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Affiliation(s)
- Jiayue Liu
- Department of Psychology and Neuroscience, Duke University, Durham, USA.
| | - Joshua Stohl
- North American Research Laboratory, MED-EL Corporation, Durham, USA
| | - Tobias Overath
- Department of Psychology and Neuroscience, Duke University, Durham, USA
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4
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Lu Y, Liu J, Li B, Wang H, Wang F, Wang S, Wu H, Han H, Hua Y. Spatial patterns of noise-induced inner hair cell ribbon loss in the mouse mid-cochlea. iScience 2024; 27:108825. [PMID: 38313060 PMCID: PMC10835352 DOI: 10.1016/j.isci.2024.108825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 10/16/2023] [Accepted: 01/03/2024] [Indexed: 02/06/2024] Open
Abstract
In the mammalian cochlea, moderate acoustic overexposure leads to loss of ribbon-type synapse between the inner hair cell (IHC) and its postsynaptic spiral ganglion neuron (SGN), causing a reduced dynamic range of hearing but not a permanent threshold elevation. A prevailing view is that such ribbon loss (known as synaptopathy) selectively impacts the low-spontaneous-rate and high-threshold SGN fibers contacting predominantly the modiolar IHC face. However, the spatial pattern of synaptopathy remains scarcely characterized in the most sensitive mid-cochlear region, where two morphological subtypes of IHC with distinct ribbon size gradients coexist. Here, we used volume electron microscopy to investigate noise exposure-related changes in the mouse IHCs with and without ribbon loss. Our quantifications reveal that IHC subtypes differ in the worst-hit area of synaptopathy. Moreover, we show relative enrichment of mitochondria in the surviving SGN terminals, providing key experimental evidence for the long-proposed role of SGN-terminal mitochondria in synaptic vulnerability.
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Affiliation(s)
- Yan Lu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People’s Hospital, Shanghai 200125, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai 200125, China
- Shanghai Institute of Precision Medicine, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
| | - Jing Liu
- Laboratory of Brain Atlas and Brain-inspired Intelligence, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Bei Li
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People’s Hospital, Shanghai 200125, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai 200125, China
| | - Haoyu Wang
- Shanghai Institute of Precision Medicine, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
| | - Fangfang Wang
- Shanghai Institute of Precision Medicine, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
| | - Shengxiong Wang
- Shanghai Institute of Precision Medicine, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People’s Hospital, Shanghai 200125, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai 200125, China
- Shanghai Institute of Precision Medicine, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
| | - Hua Han
- Laboratory of Brain Atlas and Brain-inspired Intelligence, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 101408, China
- State Key Laboratory of Multimodal Artificial Intelligence Systems, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Yunfeng Hua
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People’s Hospital, Shanghai 200125, China
- Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai 200125, China
- Shanghai Institute of Precision Medicine, Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China
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Saade M, Fernandez K, Little C, Schwam ZG, Cosetti M. Utility of Extended High-Frequency Audiograms in Clinical Practice. Laryngoscope 2024; 134:907-910. [PMID: 37497866 DOI: 10.1002/lary.30890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 05/22/2023] [Accepted: 07/01/2023] [Indexed: 07/28/2023]
Abstract
OBJECTIVES Extended high-frequency (EHF) audiometry elicits pure-tone thresholds at frequencies above 8 kHz, which are not included in routine clinical testing. This study explores the utility of EHF audiometry in patients with various audiologic symptoms despite normal-hearing thresholds at ≤8 kHz. METHODS A retrospective review was performed of all patients receiving conventional (250-8 kHz) and EHF (9-20 kHz) audiometry at a tertiary otological referral center between April 2021 and August 2022. Only patients with audiologic symptoms and pure-tone thresholds ≤25 dB HL at ≤8 kHz bilaterally on routine testing were included in subsequent analysis. EHF-PTA was defined for each ear as an average of the air conduction thresholds at 9.0, 10.0, 11.2, 12.5, 14.0, 16.0, 18.0, and 20.0 kHz. RESULTS Of the 50 patients who received EHF testing, 40 had audiologic symptoms and normal conventional audiograms at ≤8 kHz. Twenty-five of the 40 (62.5%) were found to have hearing loss in the highest frequencies. Patients with EHF hearing loss (EHF-HL) were more likely to report subjective hearing loss. Age was significantly greater in those with EHF-HL compared with those without EHF-HL, and age was positively correlated with the degree of EHF-HL. CONCLUSION EHF testing correlates with audiologic symptoms in patients with normal testing at ≤8 kHz and may be considered when standard audiometry is normal. Additional data are warranted to create an evidenced-based, clinical algorithm for EHF audiometry that can guide treatment, direct mitigation strategies, and potentially identify those at higher risk of hearing loss over time. LEVEL OF EVIDENCE 4 Laryngoscope, 134:907-910, 2024.
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Affiliation(s)
- Mia Saade
- Department of Otolaryngology-Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Karla Fernandez
- Department of Otolaryngology-Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Christine Little
- Department of Otolaryngology-Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Zachary G Schwam
- Department of Otolaryngology-Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Maura Cosetti
- Department of Otolaryngology-Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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6
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Malfeld K, Armbrecht N, Pich A, Volk HA, Lenarz T, Scheper V. Prevention of Noise-Induced Hearing Loss In Vivo: Continuous Application of Insulin-like Growth Factor 1 and Its Effect on Inner Ear Synapses, Auditory Function and Perilymph Proteins. Int J Mol Sci 2022; 24:ijms24010291. [PMID: 36613734 PMCID: PMC9820558 DOI: 10.3390/ijms24010291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/19/2022] [Accepted: 12/19/2022] [Indexed: 12/28/2022] Open
Abstract
As noise-induced hearing loss (NIHL) is a leading cause of occupational diseases, there is an urgent need for the development of preventive and therapeutic interventions. To avoid user-compliance-based problems occurring with conventional protection devices, the pharmacological prevention is currently in the focus of hearing research. Noise exposure leads to an increase in reactive oxygen species (ROS) in the cochlea. This way antioxidant agents are a promising option for pharmacological interventions. Previous animal studies reported preventive as well as therapeutic effects of Insulin-like growth factor 1 (IGF-1) in the context of NIHL. Unfortunately, in patients the time point of the noise trauma cannot always be predicted, and additive effects may occur. Therefore, continuous prevention seems to be beneficial. The present study aimed to investigate the preventive potential of continuous administration of low concentrations of IGF-1 to the inner ear in an animal model of NIHL. Guinea pigs were unilaterally implanted with an osmotic minipump. One week after surgery they received noise trauma, inducing a temporary threshold shift. Continuous IGF-1 delivery lasted for seven more days. It did not lead to significantly improved hearing thresholds compared to control animals. Quite the contrary, there is a hint for a higher noise susceptibility. Nevertheless, changes in the perilymph proteome indicate a reduced damage and better repair mechanisms through the IGF-1 treatment. Thus, future studies should investigate delivery methods enabling continuous prevention but reducing the risk of an overdosage.
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Affiliation(s)
- Kathrin Malfeld
- Department of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany
| | - Nina Armbrecht
- Department of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Andreas Pich
- Core Facility Proteomics, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Holger A. Volk
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany
| | - Thomas Lenarz
- Department of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster of Excellence “Hearing4all”, German Research Foundation (DFG; “Deutsche Forschungsgemeinschaft”), Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Verena Scheper
- Department of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Cluster of Excellence “Hearing4all”, German Research Foundation (DFG; “Deutsche Forschungsgemeinschaft”), Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
- Correspondence:
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Dolan AO, Perugia E, Kluk K. Preferred music-listening level in musicians and non-musicians. PLoS One 2022; 17:e0278845. [PMID: 36542625 PMCID: PMC9770423 DOI: 10.1371/journal.pone.0278845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 11/24/2022] [Indexed: 12/24/2022] Open
Abstract
The purpose of this study was to establish whether preferred music-listening level differed between musicians and non-musicians, and whether preferred music-listening level was related to music genre preference and lifetime noise exposure. Seventeen musicians (mean age = 29.06 years, SD = 4.74; female n = 9) and 17 non-musicians (mean age = 28.94 years, SD = 4.63; female n = 9) with clinically normal hearing were recruited to listen to six music samples from different genres and one sample of environmental sounds. Participants adjusted the listening level [dB(A)] until the music was loud and enjoyable. This was repeated three times and an average was taken. Lifetime noise exposure was estimated using the Noise Exposure Structured Interview. Preferred music-listening levels of musicians were significantly higher than non-musicians. The preferred music-listening level differed with genre preference, with the participants' favorite tracks being played at 11 dB higher level than the least favorite tracks. There was also a positive correlation between lifetime noise exposure and preferred music-listening level. Musicians prefer to listen to music at higher level than non-musicians and thus may be more susceptible to noise induced hearing loss than non-musicians. As such, musicians in particular would benefit from simple changes in lifestyle and listening habits, including increased awareness of the risks of higher listening levels, as well as the use of hearing protection.
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Affiliation(s)
- Antonia Olivia Dolan
- Manchester Centre for Audiology and Deafness (ManCAD), School of Health Science, The University of Manchester, Manchester, United Kingdom
| | - Emanuele Perugia
- Manchester Centre for Audiology and Deafness (ManCAD), School of Health Science, The University of Manchester, Manchester, United Kingdom
| | - Karolina Kluk
- Manchester Centre for Audiology and Deafness (ManCAD), School of Health Science, The University of Manchester, Manchester, United Kingdom
- * E-mail:
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Xia L, Ripley S, Jiang Z, Yin X, Yu Z, Aiken SJ, Wang J. Synaptopathy in Guinea Pigs Induced by Noise Mimicking Human Experience and Associated Changes in Auditory Signal Processing. Front Neurosci 2022; 16:935371. [PMID: 35873820 PMCID: PMC9298651 DOI: 10.3389/fnins.2022.935371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
Noise induced synaptopathy (NIS) has been researched extensively since a large amount of synaptic loss without permanent threshold shift (PTS) was found in CBA mice after a brief noise exposure. However, efforts to translate these results to humans have met with little success—and might not be possible since noise exposure used in laboratory animals is generally different from what is experienced by human subjects in real life. An additional problem is a lack of morphological data and reliable functional methods to quantify loss of afferent synapses in humans. Based on evidence for disproportionate synaptic loss for auditory nerve fibers (ANFs) with low spontaneous rates (LSR), coding-in-noise deficits (CIND) have been speculated to be the major difficulty associated with NIS without PTS. However, no robust evidence for this is available in humans or animals. This has led to a re-examination of the role of LSR ANFs in signal coding in high-level noise. The fluctuation profile model has been proposed to support a role for high-SR ANFs in the coding of high-level noise in combination with efferent control of cochlear gain. This study aimed to induce NIS by a low-level, intermittent noise exposure mimicking what is experienced in human life and examined the impact of the NIS on temporal processing under masking. It also evaluated the role of temporal fluctuation in evoking efferent feedback and the effects of NIS on this feedback.
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Affiliation(s)
- Li Xia
- Department of Otolaryngology-Head and Neck Surgery, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China
| | - Sara Ripley
- School of Communication Sciences and Disorders, Dalhousie University, Halifax, NS, Canada
| | - Zhenhua Jiang
- Department of Otolaryngology-Head and Neck Surgery, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China
| | - Xue Yin
- Department of Otolaryngology-Head and Neck Surgery, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China
| | - Zhiping Yu
- School of Communication Sciences and Disorders, Dalhousie University, Halifax, NS, Canada
| | - Steve J Aiken
- School of Communication Sciences and Disorders, Dalhousie University, Halifax, NS, Canada
| | - Jian Wang
- Department of Otolaryngology-Head and Neck Surgery, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China.,School of Communication Sciences and Disorders, Dalhousie University, Halifax, NS, Canada
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9
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Qi G, Shi L, Qin H, Jiang Q, Guo W, Yu N, Han D, Yang S. Morphology changes in the cochlea of impulse noise-induced hidden hearing loss. Acta Otolaryngol 2022; 142:455-462. [PMID: 35723705 DOI: 10.1080/00016489.2022.2086706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
BACKGROUND This study was focused on impulse noise induces hidden hearing loss. OBJECTIVES This study was designed to determine the morphology changes of noise-induced hidden hearing loss (NIHHL). METHOD Fifteen guinea pigs were divided into three groups: noise-induced hidden hearing loss (NIHHL) group, noise-induced hearing loss (NIHL) group, and normal control group. For the NIHHL group, guinea pigs were exposed to 15 times of impulse noise with peak intensity of 163 dB SPL at one time. For the NIHL group, animals were exposed to two rounds of 100 times impulse noise, and the time interval is 24 h. Auditory brain response (ABR) was tested before, immediately, 24 h, one week, and one month after noise exposure to evaluate cochlear physiology changes. One month after noise exposure, all guinea pigs in three groups were sacrificed, and basement membranes were carefully dissected immediately after ABR tests. The cochlea samples were observed by transmission electron microscopy (TEM) to find out the morphology changes. RESULT The ABR results showed that 15 times of impulse noise exposure could cause NIHHL in guinea pigs and 200 times could cause completely hearing loss. Impulse noise exposure could cause a dramatic increase of mitochondria in the inner hair cell. The structures of ribbon synapse and heminode were also obviously impaired compared to the normal group. The nerve fiber and myelin sheath remained intact after impulse noise exposure. CONCLUSION This research revealed that impulse noise could cause hidden hearing loss, and the changes in inner hair cells, ribbon synapse, and heminode all played a vital role in the pathogenesis of hidden hearing loss.
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Affiliation(s)
- Guowei Qi
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China.,Graduate School of Navy, Medical University Shanghai, Shanghai, China.,Graduate School of Chinese, PLA General Hospital Beijing, Beijing, China
| | - Lei Shi
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China.,Graduate School of Chinese, PLA General Hospital Beijing, Beijing, China
| | - Handai Qin
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China.,Graduate School of Chinese, PLA General Hospital Beijing, Beijing, China
| | - Qingqing Jiang
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China
| | - Weiwei Guo
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China
| | - Ning Yu
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China
| | - Dongyi Han
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China
| | - Shiming Yang
- Senior Department of Otolaryngology-Head & Neck Surgery, The Sixth Medical Center of PLA General Hospital, National Clinical Research Center for Otolaryngologic Diseases, State Key Lab of Hearing Science, Ministry of Education, Beijing Key Lab of Hearing Impairment Prevention and Treatment Beijing, Beijing, China
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10
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Ripley S, Xia L, Zhang Z, Aiken SJ, Wang J. Animal-to-Human Translation Difficulties and Problems With Proposed Coding-in-Noise Deficits in Noise-Induced Synaptopathy and Hidden Hearing Loss. Front Neurosci 2022; 16:893542. [PMID: 35720689 PMCID: PMC9199355 DOI: 10.3389/fnins.2022.893542] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 04/22/2022] [Indexed: 12/26/2022] Open
Abstract
Noise induced synaptopathy (NIS) and hidden hearing loss (NIHHL) have been hot topic in hearing research since a massive synaptic loss was identified in CBA mice after a brief noise exposure that did not cause permanent threshold shift (PTS) in 2009. Based upon the amount of synaptic loss and the bias of it to synapses with a group of auditory nerve fibers (ANFs) with low spontaneous rate (LSR), coding-in-noise deficit (CIND) has been speculated as the major difficult of hearing in subjects with NIS and NIHHL. This speculation is based upon the idea that the coding of sound at high level against background noise relies mainly on the LSR ANFs. However, the translation from animal data to humans for NIS remains to be justified due to the difference in noise exposure between laboratory animals and human subjects in real life, the lack of morphological data and reliable functional methods to quantify or estimate the loss of the afferent synapses by noise. Moreover, there is no clear, robust data revealing the CIND even in animals with the synaptic loss but no PTS. In humans, both positive and negative reports are available. The difficulty in verifying CINDs has led a re-examination of the hypothesis that CIND is the major deficit associated with NIS and NIHHL, and the theoretical basis of this idea on the role of LSR ANFs. This review summarized the current status of research in NIS and NIHHL, with focus on the translational difficulty from animal data to human clinicals, the technical difficulties in quantifying NIS in humans, and the problems with the SR theory on signal coding. Temporal fluctuation profile model was discussed as a potential alternative for signal coding at high sound level against background noise, in association with the mechanisms of efferent control on the cochlea gain.
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Affiliation(s)
- Sara Ripley
- School of Communication Sciences and Disorders, Dalhousie University, Halifax, NS, Canada
| | - Li Xia
- Department of Otolaryngology-Head and Neck Surgery, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China
| | - Zhen Zhang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
| | - Steve J. Aiken
- School of Communication Sciences and Disorders, Dalhousie University, Halifax, NS, Canada
| | - Jian Wang
- School of Communication Sciences and Disorders, Dalhousie University, Halifax, NS, Canada
- Department of Otolaryngology-Head and Neck Surgery, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang, China
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Bhatt IS, Washnik N, Torkamani A. Suprathreshold Auditory Measures for Detecting Early-Stage Noise-Induced Hearing Loss in Young Adults. J Am Acad Audiol 2022; 33:185-195. [PMID: 36195294 PMCID: PMC10858682 DOI: 10.1055/s-0041-1740362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2022]
Abstract
BACKGROUND Over 1 billion young adults are at risk for developing noise-induced hearing loss (NIHL) due to their habit of listening to music at loud levels. The gold standard for detecting NIHL is the audiometric notch around 3,000 to 6,000 Hz observed in pure tone audiogram. However, recent studies suggested that suprathreshold auditory measures might be more sensitive to detect early-stage NIHL in young adults. PURPOSE The present study compared suprathreshold measures in individuals with high and low noise exposure backgrounds (NEBs). We hypothesized that individuals with high NEB would exhibit reduced performance on suprathreshold measures than those with low NEB. STUDY SAMPLE An initial sample of 100 English-speaking healthy adults (18-35 years; females = 70) was obtained from five university classes. We identified 15 participants with the lowest NEB scores (10 females) and 15 participants with the highest NEB scores (10 females). We selected a sample of healthy young adults with no history of middle ear infection, and those in the low NEB group were selected with no history of impulse noise exposure. DATA COLLECTION AND ANALYSIS The study included conventional audiometry, extended high-frequency audiometry, middle ear muscle reflex (MEMR) thresholds, distortion-product otoacoustic emissions (DPOAEs), QuickSIN, and suprathreshold auditory brainstem response (ABR) measures. We used independent sample t-tests, correlation coefficients, and linear mixed model analysis to compare the audiometric measures between the NEB groups. RESULTS The prevalence of audiometric notch was low in the study sample, even for individuals with high NEB. We found that: (1) individuals with high NEB revealed significantly reduced QuickSIN performance than those with low NEB; (2) music exposure via earphone revealed a significant association with QuickSIN; (3) individuals with high NEB revealed significantly reduced DPOAEs and ABR wave I amplitude compared with individuals with low NEB; (4) MEMR and ABR latency measures showed a modest association with NEB; and (5) audiometric thresholds across the frequency range did not show statistically significant association with NEB. CONCLUSION Our results suggest that young adults with high NEB might exhibit impaired peripheral neural coding deficits leading to reduced speech-in-noise (SIN) performance despite clinically normal hearing thresholds. SIN measures might be more sensitive than audiometric notch for detecting early-stage NIHL in young adults.
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Affiliation(s)
- Ishan S Bhatt
- Department of Communication Sciences and Disorders, The University of Iowa, Iowa City, Iowa
| | - Nilesh Washnik
- Department of Communication Sciences & Disorders, Ohio University, Athens, Ohio
| | - Ali Torkamani
- Department of Integrative Structural and Computational Biology, Scripps Translational Science Institute, La Jolla, California
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Gratias P, Nasr J, Affortit C, Ceccato JC, François F, Casas F, Pujol R, Pucheu S, Puel JL, Wang J. Impulse Noise Induced Hidden Hearing Loss, Hair Cell Ciliary Changes and Oxidative Stress in Mice. Antioxidants (Basel) 2021; 10:antiox10121880. [PMID: 34942983 PMCID: PMC8698479 DOI: 10.3390/antiox10121880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 12/14/2022] Open
Abstract
Recent studies demonstrated that reversible continuous noise exposure may induce a temporary threshold shift (TTS) with a permanent degeneration of auditory nerve fibers, although hair cells remain intact. To probe the impact of TTS-inducing impulse noise exposure on hearing, CBA/J Mice were exposed to noise impulses with peak pressures of 145 dB SPL. We found that 30 min after exposure, the noise caused a mean elevation of ABR thresholds of ~30 dB and a reduction in DPOAE amplitude. Four weeks later, ABR thresholds and DPOAE amplitude were back to normal in the higher frequency region (8–32 kHz). At lower frequencies, a small degree of PTS remained. Morphological evaluations revealed a disturbance of the stereociliary bundle of outer hair cells, mainly located in the apical regions. On the other hand, the reduced suprathreshold ABR amplitudes remained until 4 weeks later. A loss of synapse numbers was observed 24 h after exposure, with full recovery two weeks later. Transmission electron microscopy revealed morphological changes at the ribbon synapses by two weeks post exposure. In addition, increased levels of oxidative stress were observed immediately after exposure, and maintained for a further 2 weeks. These results clarify the pathology underlying impulse noise-induced sensory dysfunction, and suggest possible links between impulse-noise injury, cochlear cell morphology, metabolic changes, and hidden hearing loss.
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Affiliation(s)
- Paul Gratias
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
| | - Jamal Nasr
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
| | - Corentin Affortit
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
| | - Jean-Charles Ceccato
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
| | - Florence François
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
| | - François Casas
- Unité Dynamique Du Muscle et Métabolisme (DMEM), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University Montpellier, 34060 Montpellier, France;
| | - Rémy Pujol
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
| | - Sylvie Pucheu
- Cilcare, 371 Rue du Professeur J. Blayac, 34080 Montpellier, France;
| | - Jean-Luc Puel
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
| | - Jing Wang
- Institute for Neurosciences of Montpellier (INM), University Montpellier, INSERM, 34091 Montpellier, France; (P.G.); (J.N.); (C.A.); (J.-C.C.); (F.F.); (R.P.); (J.-L.P.)
- ENT Department, Hospital and University of Montpellier, 34091 Montpellier, France
- Correspondence: ; Tel.: +33-499-636-048; Fax: +33-499-636-020
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AudioChip: A Deep Phenotyping Approach for Deconstructing and Quantifying Audiological Phenotypes of Self-Reported Speech Perception Difficulties. Ear Hear 2021; 43:1023-1036. [PMID: 34860719 PMCID: PMC9010350 DOI: 10.1097/aud.0000000000001158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES About 15% of U.S. adults report speech perception difficulties despite showing normal audiograms. Recent research suggests that genetic factors might influence the phenotypic spectrum of speech perception difficulties. The primary objective of the present study was to describe a conceptual framework of a deep phenotyping method, referred to as AudioChipping, for deconstructing and quantifying complex audiometric phenotypes. DESIGN In a sample of 70 females 18 to 35 years of age with normal audiograms (from 250 to 8000 Hz), the study measured behavioral hearing thresholds (250 to 16,000 Hz), distortion product otoacoustic emissions (1000 to 16,000 Hz), click-evoked auditory brainstem responses (ABR), complex ABR (cABR), QuickSIN, dichotic digit test score, loudness discomfort level, and noise exposure background. The speech perception difficulties were evaluated using the Speech, Spatial, and Quality of Hearing Scale-12-item version (SSQ). A multiple linear regression model was used to determine the relationship between SSQ scores and audiometric measures. Participants were categorized into three groups (i.e., high, mid, and low) using the SSQ scores before performing the clustering analysis. Audiometric measures were normalized and standardized before performing unsupervised k-means clustering to generate AudioChip. RESULTS The results showed that SSQ and noise exposure background exhibited a significant negative correlation. ABR wave I amplitude, cABR offset latency, cABR response morphology, and loudness discomfort level were significant predictors for SSQ scores. These predictors explained about 18% of the variance in the SSQ score. The k-means clustering was used to split the participants into three major groups; one of these clusters revealed 53% of participants with low SSQ. CONCLUSIONS Our study highlighted the relationship between SSQ and auditory coding precision in the auditory brainstem in normal-hearing young females. AudioChip was useful in delineating and quantifying internal homogeneity and heterogeneity in audiometric measures among individuals with a range of SSQ scores. AudioChip could help identify the genotype-phenotype relationship, document longitudinal changes in auditory phenotypes, and pair individuals in case-control groups for the genetic association analysis.
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Five-Year Longitudinal Cohort Study Determines the Critical Intervals for Periodic Audiometric Testing Based on 5070 Tests of Metallurgical Workers Exposed and Nonexposed to Noise. Ear Hear 2021; 43:81-89. [PMID: 34225319 DOI: 10.1097/aud.0000000000001077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To compare the progression of 3-, 4-, and 6-kHz thresholds (pure-tone average) over 5 years and determine the most critical period for occupational risk among workers exposed and nonexposed to noise. DESIGN Metallurgical workers were divided into 2 groups: noise-exposed and non-noise-exposed groups. The 6 initial audiometric tests of each worker were analyzed as baseline test and annual tests 1 to 5. RESULTS A total of 845 workers were included, 748 in the noise-exposed group and 97 in the non-noise-exposed group, resulting in 5070 tests analyzed. The nonexposed group showed no significant difference in the mean pure-tone averages between any of the annual tests in either ear. In the exposed group, a significant difference was observed in mean pure-tone averages between baseline and Test1 (p = 0.001 right ear; p = 0.001 left ear), between Test3 and Test4 (p = 0.002 right ear; p = 0.005 left ear), and between Test4 and Test5 (p = 0.003 right ear; p = 0.001 left ear). There was no difference between Test1 and Test2 or between Test2 and Test3 in either ear. CONCLUSIONS The progression of pure-tone averages at 3, 4, and 6 kHz differed between workers exposed and nonexposed to noise. Noise-exposed workers had a significant progressive worsening of audiometric thresholds after 3 years of employment. This study identified, in an unprecedented way, two critical periods of noise exposure: in the first year and after the third year of employment in a noisy environment.
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15
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Hidden hearing loss is associated with loss of ribbon synapses of cochlea inner hair cells. Biosci Rep 2021; 41:228102. [PMID: 33734328 PMCID: PMC8035623 DOI: 10.1042/bsr20201637] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 03/11/2021] [Accepted: 03/12/2021] [Indexed: 01/30/2023] Open
Abstract
The present study aimed to observe the changes in the cochlea ribbon synapses after repeated exposure to moderate-to-high intensity noise. Guinea pigs received 95 dB SPL white noise exposure 4 h a day for consecutive 7 days (we regarded it a medium-term and moderate-intensity noise, or MTMI noise). Animals were divided into four groups: Control, 1DPN (1-day post noise), 1WPN (1-week post noise), and 1MPN (1-month post noise). Auditory function analysis by auditory brainstem response (ABR) and compound action potential (CAP) recordings, as well as ribbon synapse morphological analyses by immunohistochemistry (Ctbp2 and PSD95 staining) were performed 1 day, 1 week, and 1 month after noise exposure. After MTMI noise exposure, the amplitudes of ABR I and III waves were suppressed. The CAP threshold was elevated, and CAP amplitude was reduced in the 1DPN group. No apparent changes in hair cell shape, arrangement, or number were observed, but the number of ribbon synapse was reduced. The 1WPN and 1MPN groups showed that part of ABR and CAP changes recovered, as well as the synapse number. The defects in cochlea auditory function and synapse changes were observed mainly in the high-frequency region. Together, repeated exposure in MTMI noise can cause hidden hearing loss (HHL), which is partially reversible after leaving the noise environment; and MTMI noise-induced HHL is associated with inner hair cell ribbon synapses.
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Takahashi M, Sanchez JT. Effects of Neurotrophin-3 on Intrinsic Neuronal Properties at a Central Auditory Structure. Neurosci Insights 2020; 15:2633105520980442. [PMID: 33354669 PMCID: PMC7734498 DOI: 10.1177/2633105520980442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 11/23/2020] [Indexed: 11/15/2022] Open
Abstract
Neurotrophins, a class of growth factor proteins that control neuronal proliferation, morphology, and apoptosis, are found ubiquitously throughout the nervous system. One particular neurotrophin (NT-3) and its cognate tyrosine receptor kinase (TrkC) have recently received attention as a possible therapeutic target for synaptopathic sensorineural hearing loss. Additionally, research shows that NT-3-TrkC signaling plays a role in establishing the sensory organization of frequency topology (ie, tonotopic order) in the cochlea of the peripheral inner ear. However, the neurotrophic effects of NT-3 on central auditory properties are unclear. In this study we examined whether NT-3-TrkC signaling affects the intrinsic electrophysiological properties at a first-order central auditory structure in chicken, known as nucleus magnocellularis (NM). Here, the expression pattern of specific neurotrophins is well known and tightly regulated. By using whole-cell patch-clamp electrophysiology, we show that NT-3 application to brainstem slices does not affect intrinsic properties of high-frequency neuronal regions but had robust effects for low-frequency neurons, altering voltage-dependent potassium functions, action potential repolarization kinetics, and passive membrane properties. We suggest that NT-3 may contribute to the precise establishment and organization of tonotopy in the central auditory pathway by playing a specialized role in regulating the development of intrinsic neuronal properties of low-frequency NM neurons.
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Affiliation(s)
- Momoko Takahashi
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
| | - Jason Tait Sanchez
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
- Department of Neurobiology, Northwestern University, Evanston, IL, USA
- The Hugh Knowles Hearing Research Center, Northwestern University, Evanston, IL, USA
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17
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Gene therapy development in hearing research in China. Gene Ther 2020; 27:349-359. [PMID: 32681137 DOI: 10.1038/s41434-020-0177-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 06/13/2020] [Accepted: 07/08/2020] [Indexed: 12/15/2022]
Abstract
Sensorineural hearing loss, the most common form of hearing impairment, is mainly attributable to genetic mutations or acquired factors, such as aging, noise exposure, and ototoxic drugs. In the field of gene therapy, advances in genetic and physiological studies and profound increases in knowledge regarding the underlying mechanisms have yielded great progress in terms of restoring the auditory function in animal models of deafness. Nonetheless, many challenges associated with the translation from basic research to clinical therapies remain to be overcome before a total restoration of auditory function can be expected. In recent years, Chinese research teams have promoted various developmental efforts in this field, including gene sequencing to identify additional potential loci that cause deafness, studies to elucidate the underlying molecular mechanisms, and research to optimize vectors and delivery routes. In this review, we summarize the state of the field and focus mainly on the progress of gene therapy in animal model studies and the optimization of therapeutic strategies in China.
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Liu X, Li L, Chen GD, Salvi R. How low must you go? Effects of low-level noise on cochlear neural response. Hear Res 2020; 392:107980. [DOI: 10.1016/j.heares.2020.107980] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/17/2020] [Accepted: 04/21/2020] [Indexed: 10/24/2022]
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19
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Fan L, Zhang Z, Wang H, Li C, Xing Y, Yin S, Chen Z, Wang J. Pre-exposure to Lower-Level Noise Mitigates Cochlear Synaptic Loss Induced by High-Level Noise. Front Syst Neurosci 2020; 14:25. [PMID: 32477075 PMCID: PMC7235317 DOI: 10.3389/fnsys.2020.00025] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 04/16/2020] [Indexed: 12/20/2022] Open
Abstract
The auditory sensory organs appear to be less damaged by exposure to high-level noise that is presented after exposure to non-traumatizing low-level noise. This phenomenon is known as the toughening or conditioning effect. Functionally, it is manifested by a reduced threshold shift, and morphologically by a reduced hair cell loss. However, it remains unclear whether prior exposure to toughening noise can mitigate the synaptic loss induced by exposure to damaging noise. Since the cochlear afferent synapse between the inner hair cells and primary auditory neurons has been identified as a novel site involved in noise-induced cochlear damage, we were interested in assessing whether this synapse can be toughened. In the present study, the synaptic loss was induced by a damaging noise exposure (106 dB SPL) and compared across Guinea pigs who had and had not been previously exposed to a toughening noise (85 dB SPL). Results revealed that the toughening noise heavily reduced the synaptic loss observed 1 day after exposure to the damaging noise. Although it was significant, the protective effect of the toughening noise on permanent synaptic loss was much smaller. Compared with cases in the control group without noise exposure, coding deficits were seen in both toughened groups, as reflected in the compound action potential (CAP) by signals with amplitude modulation. In general, the pre-exposure to the toughening noise resulted in a significantly reduced synaptic loss by the high-level noise. However, this morphological protection was not accompanied by a robust functional benefit.
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Affiliation(s)
- Liqiang Fan
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Zhen Zhang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Hui Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Chunyan Li
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Yazhi Xing
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Shankai Yin
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Zhengnong Chen
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Jian Wang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China.,Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China.,School of Communication Sciences and Disorders, Faculty of Health, Dalhousie University, Halifax, NS, Canada
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20
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Zhang Z, Fan L, Xing Y, Wang J, Aiken S, Chen Z, Wang J. Temporary Versus Permanent Synaptic Loss from Repeated Noise Exposure in Guinea Pigs and C57 Mice. Neuroscience 2020; 432:94-103. [PMID: 32114095 DOI: 10.1016/j.neuroscience.2020.02.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 01/07/2020] [Accepted: 02/23/2020] [Indexed: 01/14/2023]
Abstract
A single brief noise exposure can cause a significant loss of cochlear afferent synapses without causing permanent threshold shift. Previously we reported that the initial synaptic loss is partially reversible in Guinea pigs, indicating that synaptic loss can be categorized as either temporary or permanent. Since synaptic loss is biased to innervating auditory nerve fibers (ANFs) with low spontaneous spike rates (SSR), which are critical to the coding of in-background noise, coding-in-noise deficits (CIND) have been predicted to result from noise-induced synaptic damage. However, recent study of the noise masking of amplitude-modulation (AM) evoked compound action potentials (CAP) tailed to find evidence for such deficits in either mice or Guinea pigs. The present study sought to determine the effects of repeated noise exposure on temporary and permanent synaptic loss in Guinea pigs and C57 mice, whether such effects were additive, and whether repeated noise exposure induced CIND in Guinea pigs. The results show that the second noise exposure caused much less temporary synaptic loss and no additional permanent loss in Guinea pigs; however, an additional permanent loss was seen after the second noise was in the mice, although it was not significant. In Guinea pigs, the observed increased masking of the AM CAP provides evidence for CIND after repeated noise exposure.
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Affiliation(s)
- Zhen Zhang
- Otolaryngology Research Institute, Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Liqiang Fan
- Otolaryngology Research Institute, Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Yazhi Xing
- Otolaryngology Research Institute, Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Jiping Wang
- Otolaryngology Research Institute, Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Steve Aiken
- School of Communication Sciences and Disorders, Dalhousie University, Halifax, Canada
| | - Zhengnong Chen
- Otolaryngology Research Institute, Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
| | - Jian Wang
- Otolaryngology Research Institute, Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China; School of Communication Sciences and Disorders, Dalhousie University, Halifax, Canada.
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21
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Ilan Y. Overcoming randomness does not rule out the importance of inherent randomness for functionality. J Biosci 2019. [DOI: 10.1007/s12038-019-9958-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Xia C, Yin M, Pan P, Fang F, Zhou Y, Ji Y. Long-term exposure to moderate noise induces neural plasticity in the infant rat primary auditory cortex. Anim Cells Syst (Seoul) 2019; 23:260-269. [PMID: 31489247 PMCID: PMC6711034 DOI: 10.1080/19768354.2019.1643782] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 06/27/2019] [Accepted: 06/27/2019] [Indexed: 11/17/2022] Open
Abstract
Previous studies have reported that rearing infant rat pups in continuous moderate-level noise delayed the formation of topographic representational order and the refinement of response selectivity in the primary auditory (A1) cortex. The present study further verified that exposure to long-term moderate-intensity white noise (70 dB sound pressure level) from postnatal day (P) 12 to P30 elevated the hearing thresholds of infant rats. Compared with age-matched control rats, noise exposure (NE) rats had elevated hearing thresholds ranging from low to high frequencies, accompanied by decreased amplitudes and increased latencies of the two initial auditory brainstem response waves. The power of raw local field potential oscillations and high-frequency β oscillation in the A1 cortex of NE rats were larger, whereas the power of high-frequency γ oscillation was smaller than that of control rats. In addition, the expression levels of five glutamate receptor (GluR) subunits in the A1 cortex of NE rats were decreased with laminar specificity. These results suggest that the altered neural excitability and decreased GluR expression may underlie the delay of functional maturation in the A1 cortex, and may have implications for the treatment of hearing impairment induced by environmental noise.
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Affiliation(s)
- Chenchen Xia
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - Manli Yin
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - Ping Pan
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - Fanghao Fang
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - You Zhou
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China.,Department of Otolaryngology-Head and Neck Surgery, Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China.,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China
| | - Yonghua Ji
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
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Chen H, Xing Y, Zhang Z, Tao S, Wang H, Aiken S, Yin S, Yu D, Wang J. Coding-in-Noise Deficits are Not Seen in Responses to Amplitude Modulation in Subjects with cochlear Synaptopathy Induced by a Single Noise Exposure. Neuroscience 2019; 400:62-71. [PMID: 30615912 DOI: 10.1016/j.neuroscience.2018.12.048] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 12/22/2018] [Accepted: 12/27/2018] [Indexed: 11/30/2022]
Abstract
Since the first report of noise-induced synaptic damage in animals without permanent threshold shifts (PTSs), the concept of noise-induced hidden hearing loss (NIHHL) has been proposed to cover the functional deficits in hearing associated with noise-induced synaptopathy. Moreover, the potential functional deficit associated with the noise-induced synaptopathy has been largely attributed to the loss of auditory nerve fibers (ANFs) with a low spontaneous spike rate (SSR). As this group of ANFs is critical for coding at suprathreshold levels and in noisy background, coding-in-noise deficit (CIND) has been considered to be main consequence of the synaptopathy. However, such deficits have not been verified after a single, brief exposure to noise without PTS. In the present study, synaptopathy was generated by such noise exposure in both mice and guinea pigs. Responses to amplitude modulation (AM) were recorded at a high sound level in combination with masking to evaluate the existence of CINDs that might be associated with loss of low-SSR ANFs. An overall reduction in response amplitude was seen in AM-evoked compound action potential (CAP). However, no such reduction was seen in the scalp-recorded envelope following response (EFR), suggesting a compensation due to increased central gain. Moreover, there was no significant difference in masking effect between the control and noise groups. The results suggest that either there is no significant CIND after the synaptopathy we created, or the AM response tested with our protocol was not sufficiently sensitive to detect such a deficit; far-field EFR is not sensitive to cochlear pathology.
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Affiliation(s)
- Hengchao Chen
- Otolaryngology Research Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Yazhi Xing
- Otolaryngology Research Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Zhen Zhang
- Otolaryngology Research Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Shan Tao
- Department of Neonatal Pediatrics, Children's Hospital, Xiamen, China
| | - Hui Wang
- Otolaryngology Research Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Steve Aiken
- School of Communication Sciences and Disorder, Dalhousie University, Halifiax, Canada
| | - Shankai Yin
- Otolaryngology Research Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Dongzhen Yu
- Otolaryngology Research Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
| | - Jian Wang
- Otolaryngology Research Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China; School of Communication Sciences and Disorder, Dalhousie University, Halifiax, Canada.
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