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Fujihira H, Yamagishi S, Furukawa S, Kashino M. Auditory brainstem response to paired clicks as a candidate marker of cochlear synaptopathy in humans. Clin Neurophysiol 2024; 165:44-54. [PMID: 38959535 DOI: 10.1016/j.clinph.2024.06.005] [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: 04/04/2024] [Revised: 06/02/2024] [Accepted: 06/08/2024] [Indexed: 07/05/2024]
Abstract
OBJECTIVE This study aimed to evaluate whether auditory brainstem response (ABR) using a paired-click stimulation paradigm could serve as a tool for detecting cochlear synaptopathy (CS). METHODS The ABRs to single-clicks and paired-clicks with various inter-click intervals (ICIs) and scores for word intelligibility in degraded listening conditions were obtained from 57 adults with normal hearing. The wave I peak amplitude and root mean square values for the post-wave I response within a range delayed from the wave I peak (referred to as the RMSpost-w1) were calculated for the single- and second-click responses. RESULTS The wave I peak amplitudes did not correlate with age except for the second-click responses at an ICI of 7 ms, and the word intelligibility scores. However, we found that the RMSpost-w1 values for the second-click responses significantly decreased with increasing age. Moreover, the RMSpost-w1 values for the second-click responses at an ICI of 5 ms correlated significantly with the scores for word intelligibility in degraded listening conditions. CONCLUSIONS The magnitude of the post-wave I response for the second-click response could serve as a tool for detecting CS in humans. SIGNIFICANCE Our findings shed new light on the analytical methods of ABR for quantifying CS.
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Affiliation(s)
- Haruna Fujihira
- NTT Communication Science Laboratories, Atsugi, Kanagawa, Japan; Department of Informatics, Faculty of Information Science and Electrical Engineering, Kyushu University, Fukuoka, Japan.
| | | | - Shigeto Furukawa
- NTT Communication Science Laboratories, Atsugi, Kanagawa, Japan; Graduate School of Public Health, Shizuoka Graduate University of Public Health, Shizuoka, Japan; Speech-Language-Hearing Center, Shizuoka General Hospital, Shizuoka, Japan
| | - Makio Kashino
- NTT Communication Science Laboratories, Atsugi, Kanagawa, Japan
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Kamerer AM, Harris SE, Wichman CS, Rasetshwane DM, Neely ST. The relationship and interdependence of auditory thresholds, proposed behavioural measures of hidden hearing loss, and physiological measures of auditory function. Int J Audiol 2024:1-14. [PMID: 39180321 DOI: 10.1080/14992027.2024.2391986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 07/12/2024] [Accepted: 08/07/2024] [Indexed: 08/26/2024]
Abstract
OBJECTIVES Standard diagnostic measures focus on threshold elevation but hearing concerns may occur independently of threshold elevation - referred to as "hidden hearing loss" (HHL). A deeper understanding of HHL requires measurements that locate dysfunction along the auditory pathway. This study aimed to describe the relationship and interdependence between certain behavioural and physiological measures of auditory function that are thought to be indicative of HHL. DESIGN Data were collected on a battery of behavioural and physiological measures of hearing. Threshold-dependent variance was removed from each measure prior to generating a multiple regression model of the behavioural measures using the physiological measures. STUDY SAMPLE 224 adults in the United States with audiometric thresholds ≤65 dB HL. RESULTS Thresholds accounted for between 21 and 60% of the variance in our behavioural measures and 5-51% in our physiological measures of hearing. There was no evidence that the behavioural measures of hearing could be predicted by the selected physiological measures. CONCLUSIONS Several proposed behavioural measures for HHL: thresholds-in-noise, frequency-modulation detection, and speech recognition in difficult listening conditions, are influenced by hearing sensitivity and are not predicted by outer hair cell or auditory nerve physiology. Therefore, these measures may not be able to assess threshold-independent hearing disorders.
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Affiliation(s)
| | - Sara E Harris
- Boys Town National Research Hospital, Omaha, NE, USA
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Helfer KS, Maldonado L, Matthews LJ, Simpson AN, Dubno JR. Extended High-Frequency Thresholds: Associations With Demographic and Risk Factors, Cognitive Ability, and Hearing Outcomes in Middle-Aged and Older Adults. Ear Hear 2024:00003446-990000000-00309. [PMID: 38987892 DOI: 10.1097/aud.0000000000001531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
OBJECTIVES This study had two objectives: to examine associations between extended high-frequency (EHF) thresholds, demographic factors (age, sex, race/ethnicity), risk factors (cardiovascular, smoking, noise exposure, occupation), and cognitive abilities; and to determine variance explained by EHF thresholds for speech perception in noise, self-rated workload/effort, and self-reported hearing difficulties. DESIGN This study was a retrospective analysis of a data set from the MUSC Longitudinal Cohort Study of Age-related Hearing Loss. Data from 347 middle-aged adults (45 to 64 years) and 694 older adults (≥ 65 years) were analyzed for this study. Speech perception was quantified using low-context Speech Perception In Noise (SPIN) sentences. Self-rated workload/effort was measured using the effort prompt from the National Aeronautics and Space Administration-Task Load Index. Self-reported hearing difficulty was assessed using the Hearing Handicap Inventory for the Elderly/Adults. The Wisconsin Card Sorting Task and the Stroop Neuropsychological Screening Test were used to assess selected cognitive abilities. Pure-tone averages representing conventional and EHF thresholds between 9 and 12 kHz (PTA(9 - 12 kHz)) were utilized in simple linear regression analyses to examine relationships between thresholds and demographic and risk factors or in linear regression models to assess the contributions of PTA(9 - 12 kHz) to the variance among the three outcomes of interest. Further analyses were performed on a subset of individuals with thresholds ≤ 25 dB HL at all conventional frequencies to control for the influence of hearing loss on the association between PTA(9 - 12 kHz) and outcome measures. RESULTS PTA(9 - 12 kHz) was higher in males than females, and was higher in White participants than in racial Minority participants. Linear regression models showed the associations between cardiovascular risk factors and PTA(9 - 12 kHz) were not statistically significant. Older adults who reported a history of noise exposure had higher PTA(9 - 12 kHz) than those without a history, while associations between noise history and PTA(9 - 12 kHz) did not reach statistical significance for middle-aged participants. Linear models adjusting for age, sex, race and noise history showed that higher PTA(9 - 12 kHz) was associated with greater self-perceived hearing difficulty and poorer speech recognition scores in noise for both middle-aged and older participants. Workload/effort was significantly related to PTA(9 - 12 kHz) for middle-aged, but not older, participants, while cognitive task performance was correlated with PTA(9 - 12 kHz) only for older participants. In general, PTA(9 - 12 kHz)did not account for additional variance in outcome measures as compared to conventional pure-tone thresholds, with the exception of self-reported hearing difficulties in older participants. Linear models adjusting for age and accounting for subject-level correlations in the subset analyses revealed no association between PTA(9 - 12 kHz)and outcomes of interest. CONCLUSIONS EHF thresholds show age-, sex-, and race-related patterns of elevation that are similar to what is observed for conventional thresholds. The current results support the need for more research to determine the utility of adding EHF thresholds to routine audiometric assessment with middle-aged and older adults.
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Affiliation(s)
- Karen S Helfer
- Department of Speech, Language, and Hearing Sciences, University of Massachusetts Amherst, Amherst, Massachusetts, USA
| | - Lizmarie Maldonado
- Department of Healthcare Leadership and Management, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Lois J Matthews
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Annie N Simpson
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Judy R Dubno
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, USA
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Lee C, Hartsock JJ, Salt AN, Lichtenhan JT. A Guinea Pig Model Suggests That Objective Assessment of Acoustic Hearing Preservation in Human Ears With Cochlear Implants Is Confounded by Shifts in the Spatial Origin of Acoustically Evoked Potential Measurements Along the Cochlear Length. Ear Hear 2024; 45:666-678. [PMID: 38178312 DOI: 10.1097/aud.0000000000001457] [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: 01/06/2024]
Abstract
OBJECTIVES Our recent empirical findings have shown that the auditory nerve compound action potential (CAP) evoked by a low-level tone burst originates from a narrow cochlear region tuned to the tone burst frequency. At moderate to high sound levels, the origins shift to the most sensitive audiometric regions rather than the extended high-frequency regions of the cochlear base. This means that measurements evoked from extended high-frequency sound stimuli can shift toward the apex with increasing level. Here we translate this study to understand the spatial origin of acoustically evoked responses from ears that receive cochlear implants, an emerging area of research and clinical practice that is not completely understood. An essential step is to first understand the influence of the cochlear implant in otherwise naive ears. Our objective was to understand how function of the high-frequency cochlear base, which can be excited by the intense low-frequency sounds that are frequently used for objective intra- and postoperative monitoring, can be influenced by the presence of the cochlear implant. DESIGN We acoustically evoked responses and made measurements with an electrode placed near the guinea pig round window. The cochlear implant was not utilized for either electrical stimulation or recording purposes. With the cochlear implant in situ, CAPs were acoustically evoked from 2 to 16 kHz tone bursts of various levels while utilizing the slow perfusion of a kainic acid solution from the cochlear apex to the cochlear aqueduct in the base, which sequentially reduced neural responses from finely spaced cochlear frequency regions. This cochlear perfusion technique reveals the spatial origin of evoked potential measurements and provides insight on what influence the presence of an implant has on acoustical hearing. RESULTS Threshold measurements at 3 to 11 kHz were elevated by implantation. In an individual ear, thresholds were elevated and lowered as cochlear implant was respectively inserted and removed, indicative of "conductive hearing loss" induced by the implant. The maximum threshold elevation occurred at most sensitive region of the naive guinea pig ear (33.66 dB at 8 kHz), making 11 kHz the most sensitive region to acoustic sounds for guinea pig ears with cochlear implants. Conversely, the acute implantation did not affect the low-frequency, 500 Hz thresholds and suprathreshold function, as shown by the auditory nerve overlapped waveform. As the sound pressure level of the tone bursts increased, mean data show that the spatial origin of CAPs along the cochlear length shifted toward the most sensitive cochlear region of implanted ears, not the extended high-frequency cochlear regions. However, data from individual ears showed that after implantation, measurements from moderate to high sound pressure levels originate in places that are unique to each ear. CONCLUSIONS Alterations to function of the cochlear base from the in situ cochlear implant may influence objective measurements of implanted ears that are frequently made with intense low-frequency sound stimuli. Our results from guinea pigs advance the interpretation of measurements used to understand how and when residual acoustic hearing is lost in human ears receiving a cochlear implant.
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Affiliation(s)
- Choongheon Lee
- Department of Otolaryngology, University of Rochester, Rochester, New York, USA
| | - Jared J Hartsock
- Department of Cochlear Surgery, Turner Scientific, Inc., Jacksonville, Illinois, USA
| | - Alec N Salt
- Department of Pharmacokinetics, Turner Scientific, Inc., Jacksonville, Illinois, USA
| | - Jeffery T Lichtenhan
- Department of Otolaryngology, University of South Florida Morsani School of Medicine, Tampa, Florida, USA
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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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Prendergast G, Sathe TS, Heinrich A, Munro KJ. Acoustic reflexes: should we be paying more attention? Int J Audiol 2024; 63:221-225. [PMID: 36811451 DOI: 10.1080/14992027.2023.2174455] [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: 08/13/2022] [Revised: 01/21/2023] [Accepted: 01/23/2023] [Indexed: 02/24/2023]
Abstract
OBJECTIVE The clinical audiology test battery often involves playing physically simple sounds with questionable ecological value to the listener. In this technical report, we revisit how valid this approach is using an automated, involuntary auditory response; the acoustic reflex threshold (ART). DESIGN The ART was estimated four times in each individual in a quasi-random ordering of task conditions. The baseline condition (referred to as Neutral) measured the ART following a standard clinical practice. Three experimental conditions were then used in which a secondary task was performed whilst the reflex was measured: auditory attention, auditory distraction and visual distraction tasks. STUDY SAMPLE Thirty-eight participants (27 males) with a mean age of 23 years were tested. All participants were audiometrically healthy. RESULTS The ART was elevated when a visual task was performed at the same time as the measurements were taken. Performing an auditory task did not affect the ART. CONCLUSIONS These data indicate that simple audiometric measures widely used in the clinic, can be affected by central, non-auditory processes even in healthy, normal-hearing volunteers. The role of cognition and attention on auditory responses will become ever more important in the coming years.
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Affiliation(s)
- Garreth Prendergast
- Manchester Centre for Audiology and Deafness (ManCAD), School of Health Sciences, The University of Manchester, Manchester, UK
| | - Tanvi S Sathe
- Manchester Centre for Audiology and Deafness (ManCAD), School of Health Sciences, The University of Manchester, Manchester, UK
| | - Antje Heinrich
- Manchester Centre for Audiology and Deafness (ManCAD), School of Health Sciences, The University of Manchester, Manchester, UK
| | - Kevin J Munro
- Manchester Centre for Audiology and Deafness (ManCAD), School of Health Sciences, The University of Manchester, Manchester, UK
- Manchester Academic Health Science Centre, Manchester University Hospitals NHS Foundation Trust, Manchester, UK
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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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Bramhall NF, McMillan GP. Perceptual Consequences of Cochlear Deafferentation in Humans. Trends Hear 2024; 28:23312165241239541. [PMID: 38738337 DOI: 10.1177/23312165241239541] [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: 05/14/2024] Open
Abstract
Cochlear synaptopathy, a form of cochlear deafferentation, has been demonstrated in a number of animal species, including non-human primates. Both age and noise exposure contribute to synaptopathy in animal models, indicating that it may be a common type of auditory dysfunction in humans. Temporal bone and auditory physiological data suggest that age and occupational/military noise exposure also lead to synaptopathy in humans. The predicted perceptual consequences of synaptopathy include tinnitus, hyperacusis, and difficulty with speech-in-noise perception. However, confirming the perceptual impacts of this form of cochlear deafferentation presents a particular challenge because synaptopathy can only be confirmed through post-mortem temporal bone analysis and auditory perception is difficult to evaluate in animals. Animal data suggest that deafferentation leads to increased central gain, signs of tinnitus and abnormal loudness perception, and deficits in temporal processing and signal-in-noise detection. If equivalent changes occur in humans following deafferentation, this would be expected to increase the likelihood of developing tinnitus, hyperacusis, and difficulty with speech-in-noise perception. Physiological data from humans is consistent with the hypothesis that deafferentation is associated with increased central gain and a greater likelihood of tinnitus perception, while human data on the relationship between deafferentation and hyperacusis is extremely limited. Many human studies have investigated the relationship between physiological correlates of deafferentation and difficulty with speech-in-noise perception, with mixed findings. A non-linear relationship between deafferentation and speech perception may have contributed to the mixed results. When differences in sample characteristics and study measurements are considered, the findings may be more consistent.
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Affiliation(s)
- Naomi F Bramhall
- VA National Center for Rehabilitative Auditory Research, Veterans Affairs Portland Health Care System, Portland, OR, USA
- Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science University, Portland, OR, USA
| | - Garnett P McMillan
- VA National Center for Rehabilitative Auditory Research, Veterans Affairs Portland Health Care System, Portland, OR, USA
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De Poortere N, Verhulst S, Degeest S, Keshishzadeh S, Dhooge I, Keppler H. Evaluation of Lifetime Noise Exposure History Reporting. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2023; 66:5129-5151. [PMID: 37988687 DOI: 10.1044/2023_jslhr-23-00266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
PURPOSE The purpose of this study is to critically evaluate lifetime noise exposure history (LNEH) reporting. First, two different approaches to evaluate the cumulative LNEH were compared. Second, individual LNEH was associated with the subjects' hearing status. Third, loudness estimates of exposure activities, by means of Jokitulppo- and Ferguson-based exposure levels, were compared with dosimeter sound-level measurements. METHOD One hundred one young adults completed the questionnaires, and a subgroup of 30 subjects underwent audiological assessment. Pure-tone audiometry, speech-in-noise intelligibility, distortion product otoacoustic emissions, auditory brainstem responses, and envelope following responses were included. Fifteen out of the 30 subjects took part in a noisy activity while wearing a dosimeter. RESULTS First, results demonstrate that the structured questionnaire yielded a greater amount of information pertaining to the diverse activities, surpassing the insights obtained from an open-ended questionnaire. Second, no significant correlations between audiological assessment and LNEH were found. Lastly, the results indicate that Ferguson-based exposure levels offer a more precise estimation of the actual exposure levels, in contrast to Jokitulppo-based estimates. CONCLUSIONS We propose several recommendations for determining the LNEH. First, it is vital to define accurate loudness categories and corresponding allocated levels, with a preference for the loudness levels proposed by Ferguson et al. (2019), as identified in this study. Second, a structured questionnaire regarding LNEH is recommended, discouraging open-ended questioning. Third, it is essential to include a separate category exclusively addressing work-related activities, encompassing various activities for more accurate surveying.
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Affiliation(s)
- Nele De Poortere
- Department of Rehabilitation Sciences-Audiology, Ghent University, Belgium
| | - Sarah Verhulst
- Department of Information Technology-Hearing Technology at WAVES, Ghent University, Belgium
| | - Sofie Degeest
- Department of Rehabilitation Sciences-Audiology, Ghent University, Belgium
| | - Sarineh Keshishzadeh
- Department of Information Technology-Hearing Technology at WAVES, Ghent University, Belgium
| | - Ingeborg Dhooge
- Department of Ear, Nose and Throat, Ghent University Hospital, Belgium
- Department of Head and Skin, Ghent University, Belgium
| | - Hannah Keppler
- Department of Rehabilitation Sciences-Audiology, Ghent University, Belgium
- Department of Head and Skin, Ghent University, Belgium
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Vasilkov V, Caswell-Midwinter B, Zhao Y, de Gruttola V, Jung DH, Liberman MC, Maison SF. Evidence of cochlear neural degeneration in normal-hearing subjects with tinnitus. Sci Rep 2023; 13:19870. [PMID: 38036538 PMCID: PMC10689483 DOI: 10.1038/s41598-023-46741-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 11/04/2023] [Indexed: 12/02/2023] Open
Abstract
Tinnitus, reduced sound-level tolerance, and difficulties hearing in noisy environments are the most common complaints associated with sensorineural hearing loss in adult populations. This study aims to clarify if cochlear neural degeneration estimated in a large pool of participants with normal audiograms is associated with self-report of tinnitus using a test battery probing the different stages of the auditory processing from hair cell responses to the auditory reflexes of the brainstem. Self-report of chronic tinnitus was significantly associated with (1) reduced cochlear nerve responses, (2) weaker middle-ear muscle reflexes, (3) stronger medial olivocochlear efferent reflexes and (4) hyperactivity in the central auditory pathways. These results support the model of tinnitus generation whereby decreased neural activity from a damaged cochlea can elicit hyperactivity from decreased inhibition in the central nervous system.
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Affiliation(s)
- Viacheslav Vasilkov
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - Benjamin Caswell-Midwinter
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - Yan Zhao
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
| | - Victor de Gruttola
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, 02114, USA
| | - David H Jung
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - M Charles Liberman
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA
| | - Stéphane F Maison
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA, 02114, USA.
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02114, USA.
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11
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Lunardelo PP, Meneghelli LC, Zanchetta S. Self-reported hearing difficulties and speech-in-noise test performance - what can we find behind a "normal" audiogram? Codas 2023; 35:e20220111. [PMID: 38018646 DOI: 10.1590/2317-1782/20232022111p] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 11/30/2022] [Indexed: 11/30/2023] Open
Abstract
PURPOSE To investigate complaints of difficulty understanding speech in the presence of noise in subjects without hearing loss and their performance on a speech-in-noise test. METHODS Thirty-nine subjects aged 18 to 59 years and 11 months were divided into four groups according to their decade of life. They underwent audiometry, tympanometry, auditory processing tests, the Mini-Mental State Examination, a self-report on auditory perception combined with the Amsterdam Inventory for Auditory Disability and Handicap (Pt-AIADH), and a sentence test in silence and in noise. RESULTS All groups scored high on the Pt-AIADH domains, with the highest average score obtained for the noise intelligibility domain. There were differences between G18 vs. G40, G18 vs. G50, and G30 vs. G50 for auditory self-perception in noise intelligibility, and differences between the youngest and all other groups on the speech-in-noise test in particular, with a lower signal-to-noise ratio for older adults. We also identified a moderate and significant correlation between intelligibility in noise and the speech-in-noise test. CONCLUSION Normal hearers of all age groups complained of intelligibility in noise. We found that the higher an individual's auditory difficulty in this domain, the worse their performance on the speech-in-noise test; this is especially true for middle-aged adults.
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Affiliation(s)
- Pamela Papile Lunardelo
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto - FFCLRP, Universidade de São Paulo - USP - Ribeirão Preto (SP), Brasil
| | - Laura Caetano Meneghelli
- Faculdade de Medicina de Ribeirão Preto - FMRP, Universidade de São Paulo - USP - Ribeirão Preto (SP), Brasil
| | - Sthella Zanchetta
- Faculdade de Medicina de Ribeirão Preto - FMRP, Universidade de São Paulo - USP - Ribeirão Preto (SP), Brasil
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12
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Colla MDF, Lunardelo PP, Dias FAM. Cochlear synaptopathy and hidden hearing loss: a scoping review. Codas 2023; 36:e20230032. [PMID: 37991055 DOI: 10.1590/2317-1782/20232023032pt] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 07/10/2023] [Indexed: 11/23/2023] Open
Abstract
PURPOSE To identify the pathophysiological definitions adopted by studies investigating "cochlear synaptopathy" (CS) and "hidden hearing loss" (HHL). RESEARCH STRATEGIES The combination of keywords "Auditory Synaptopathy" or "Neuronal Synaptopathy" or "Hidden Hearing Loss" with "etiology" or "causality" or "diagnosis" was used in the databases EMBASE, Pubmed (MEDLINE), CINAHL (EBSCO), and Web of Science. SELECTION CRITERIA Studies that investigated CS or HHL in humans using behavioral and/or electrophysiological procedures were included. DATA ANALYSIS Data analysis and extraction were performed with regard to terminology, definitions, and population. RESULTS 49 articles were included. Of these, 61.2% used the CS terminology, 34.7% used both terms, and 4.1% used HHL. The most-studied conditions were exposure to noise and tinnitus. CONCLUSION CS terminology was used in most studies, referring to the pathophysiological process of deafferentiation between the cochlear nerve fibers and inner hair cells.
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Affiliation(s)
- Marina de Figueiredo Colla
- Departamento de Fonoaudiologia, Pontifícia Universidade Católica de Minas Gerais - PUC MG - Belo Horizonte (MG), Brasil
| | - Pamela Papile Lunardelo
- Programa de Pós-graduação em Psicobiologia, Universidade de São Paulo de Ribeirão Preto - USP RP - Ribeirão Preto (SP), Brasil
| | - Fernanda Abalen Martins Dias
- Departamento de Fonoaudiologia, Pontifícia Universidade Católica de Minas Gerais - PUC MG - Belo Horizonte (MG), Brasil
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Houmøller SS, Tsai LT, Wolff A, Kaithali Narayanan S, Hougaard DD, Gaihede M, Hammershøi D, Neher T, Godballe C, Schmidt JH. A history of occupational noise exposure is associated with steep-slope audiograms and poorer self-reported hearing-aid outcomes. Int J Audiol 2023:1-13. [PMID: 37909290 DOI: 10.1080/14992027.2023.2272558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 10/11/2023] [Indexed: 11/03/2023]
Abstract
OBJECTIVE To investigate the effects of previous occupational noise exposure in older adults with hearing loss on (1) audiometric configuration and acoustic reflex (AR) thresholds and (2) self-reported hearing abilities and hearing aid (HA) effectiveness. DESIGN A prospective observational study. STUDY SAMPLE The study included 1176 adults (≥60 years) with bilateral sensorineural hearing loss. Pure-tone audiometry, AR thresholds, and responses to the abbreviated version of the Speech, Spatial, and Qualities of Hearing Scale (SSQ12) and the International Outcome Inventory for Hearing Aids (IOI-HA) questionnaire were obtained, along with information about previous occupational noise exposure. RESULTS Greater occupational noise exposure was associated with a higher prevalence of steeply sloping audiograms in men and women and a 0.32 (95% CI: -0.57; -0.06) scale points lower mean SSQ12 total score among noise-exposed men. AR thresholds did not show a significant relation to noise-exposure status, but hearing thresholds at a given frequency were related to elevated AR thresholds at the same frequency. CONCLUSIONS A noise exposure history is linked to steeper audiograms in older adults with hearing loss as well as to poorer self-reported hearing abilities in noise-exposed men. More attention to older adults with previous noise exposure is warranted in hearing rehabilitation.
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Affiliation(s)
- Sabina Storbjerg Houmøller
- Research Unit for ORL - Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
- OPEN, Odense Patient Data Explorative Network, Odense University Hospital, Odense, Denmark
| | - Li-Tang Tsai
- Research Unit for ORL - Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
| | - Anne Wolff
- Department of Otolaryngology, Head and Neck Surgery and Audiology, Aalborg University Hospital, Aalborg, Denmark
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | | | - Dan Dupont Hougaard
- Department of Otolaryngology, Head and Neck Surgery and Audiology, Aalborg University Hospital, Aalborg, Denmark
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - Michael Gaihede
- Department of Otolaryngology, Head and Neck Surgery and Audiology, Aalborg University Hospital, Aalborg, Denmark
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - Dorte Hammershøi
- Section for AI and Sound, Department of Electronic Systems, Aalborg University, Aalborg, Denmark
| | - Tobias Neher
- Research Unit for ORL - Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
| | - Christian Godballe
- Research Unit for ORL - Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
- OPEN, Odense Patient Data Explorative Network, Odense University Hospital, Odense, Denmark
| | - Jesper Hvass Schmidt
- Research Unit for ORL - Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
- OPEN, Odense Patient Data Explorative Network, Odense University Hospital, Odense, Denmark
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Balan JR, Rodrigo H, Saxena U, Mishra SK. Explainable machine learning reveals the relationship between hearing thresholds and speech-in-noise recognition in listeners with normal audiograms. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 154:2278-2288. [PMID: 37823779 DOI: 10.1121/10.0021303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 09/17/2023] [Indexed: 10/13/2023]
Abstract
Some individuals complain of listening-in-noise difficulty despite having a normal audiogram. In this study, machine learning is applied to examine the extent to which hearing thresholds can predict speech-in-noise recognition among normal-hearing individuals. The specific goals were to (1) compare the performance of one standard (GAM, generalized additive model) and four machine learning models (ANN, artificial neural network; DNN, deep neural network; RF, random forest; XGBoost; eXtreme gradient boosting), and (2) examine the relative contribution of individual audiometric frequencies and demographic variables in predicting speech-in-noise recognition. Archival data included thresholds (0.25-16 kHz) and speech recognition thresholds (SRTs) from listeners with clinically normal audiograms (n = 764 participants or 1528 ears; age, 4-38 years old). Among the machine learning models, XGBoost performed significantly better than other methods (mean absolute error; MAE = 1.62 dB). ANN and RF yielded similar performances (MAE = 1.68 and 1.67 dB, respectively), whereas, surprisingly, DNN showed relatively poorer performance (MAE = 1.94 dB). The MAE for GAM was 1.61 dB. SHapley Additive exPlanations revealed that age, thresholds at 16 kHz, 12.5 kHz, etc., on the order of importance, contributed to SRT. These results suggest the importance of hearing in the extended high frequencies for predicting speech-in-noise recognition in listeners with normal audiograms.
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Affiliation(s)
- Jithin Raj Balan
- Department of Speech, Language and Hearing Sciences, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Hansapani Rodrigo
- School of Mathematical and Statistical Sciences, The University of Texas Rio Grande Valley, Edinburg, Texas 78539, USA
| | - Udit Saxena
- Department of Audiology and Speech-Language Pathology, Gujarat Medical Education and Research Society, Medical College and Hospital, Ahmedabad, 380060, India
| | - Srikanta K Mishra
- Department of Speech, Language and Hearing Sciences, The University of Texas at Austin, Austin, Texas 78712, USA
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15
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Haggerty RA, Hutson KA, Riggs WJ, Brown KD, Pillsbury HC, Adunka OF, Buchman CA, Fitzpatrick DC. Assessment of cochlear synaptopathy by electrocochleography to low frequencies in a preclinical model and human subjects. Front Neurol 2023; 14:1104574. [PMID: 37483448 PMCID: PMC10361575 DOI: 10.3389/fneur.2023.1104574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 06/19/2023] [Indexed: 07/25/2023] Open
Abstract
Cochlear synaptopathy is the loss of synapses between the inner hair cells and the auditory nerve despite survival of sensory hair cells. The findings of extensive cochlear synaptopathy in animals after moderate noise exposures challenged the long-held view that hair cells are the cochlear elements most sensitive to insults that lead to hearing loss. However, cochlear synaptopathy has been difficult to identify in humans. We applied novel algorithms to determine hair cell and neural contributions to electrocochleographic (ECochG) recordings from the round window of animal and human subjects. Gerbils with normal hearing provided training and test sets for a deep learning algorithm to detect the presence of neural responses to low frequency sounds, and an analytic model was used to quantify the proportion of neural and hair cell contributions to the ECochG response. The capacity to detect cochlear synaptopathy was validated in normal hearing and noise-exposed animals by using neurotoxins to reduce or eliminate the neural contributions. When the analytical methods were applied to human surgical subjects with access to the round window, the neural contribution resembled the partial cochlear synaptopathy present after neurotoxin application in animals. This result demonstrates the presence of viable hair cells not connected to auditory nerve fibers in human subjects with substantial hearing loss and indicates that efforts to regenerate nerve fibers may find a ready cochlear substrate for innervation and resumption of function.
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Affiliation(s)
- Raymond A. Haggerty
- Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Kendall A. Hutson
- Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - William J. Riggs
- Department of Otolaryngology, The Ohio State University, Columbus, OH, United States
| | - Kevin D. Brown
- Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- University of North Carolina School of Medicine, Chapel Hill, NC, United States
| | - Harold C. Pillsbury
- Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- University of North Carolina School of Medicine, Chapel Hill, NC, United States
| | - Oliver F. Adunka
- Department of Otolaryngology, The Ohio State University, Columbus, OH, United States
| | - Craig A. Buchman
- Department of Otolaryngology, Washington University in St. Louis, St. Louis, MO, United States
| | - Douglas C. Fitzpatrick
- Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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16
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Kempfle JS, Jung DH. Experimental drugs for the prevention or treatment of sensorineural hearing loss. Expert Opin Investig Drugs 2023; 32:643-654. [PMID: 37598357 DOI: 10.1080/13543784.2023.2242253] [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: 02/15/2023] [Accepted: 07/26/2023] [Indexed: 08/22/2023]
Abstract
INTRODUCTION Sensorineural hearing loss results in irreversible loss of inner ear hair cells and spiral ganglion neurons. Reduced sound detection and speech discrimination can span all ages, and sensorineural hearing rehabilitation is limited to amplification with hearing aids or cochlear implants. Recent insights into experimental drug treatments for inner ear regeneration and otoprotection have paved the way for clinical trials in order to restore a more physiological hearing experience. Paired with the development of innovative minimally invasive approaches for drug delivery to the inner ear, new, emerging treatments for hearing protection and restoration are within reach. AREAS COVERED This expert opinion provides an overview of the latest experimental drug therapies to protect from and to restore sensorineural hearing loss. EXPERT OPINION The degree and type of cellular damage to the cochlea, the responsiveness of remaining, endogenous cells to regenerative treatments, and the duration of drug availability within cochlear fluids will determine the success of hearing protection or restoration.
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Affiliation(s)
- Judith S Kempfle
- Department of Otolaryngology, Massachusetts Eye and Ear, Boston, MA, USA
- Department of Otolaryngology, Head & Neck Surgery, Harvard Medical School, Boston, MA, USA
- Department of Otolaryngology, UMass Memorial Medical Center, Worcester, MA, USA
- Department of Otolaryngology, Head & Neck Surgery, University of Massachusetts Medical School, Worcester, MA, USA
| | - David H Jung
- Department of Otolaryngology, Massachusetts Eye and Ear, Boston, MA, USA
- Department of Otolaryngology, Head & Neck Surgery, Harvard Medical School, Boston, MA, USA
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17
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Auditory Electrophysiological and Perceptual Measures in Student Musicians with High Sound Exposure. Diagnostics (Basel) 2023; 13:diagnostics13050934. [PMID: 36900080 PMCID: PMC10000734 DOI: 10.3390/diagnostics13050934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/05/2022] [Accepted: 02/26/2023] [Indexed: 03/06/2023] Open
Abstract
This study aimed to determine (a) the influence of noise exposure background (NEB) on the peripheral and central auditory system functioning and (b) the influence of NEB on speech recognition in noise abilities in student musicians. Twenty non-musician students with self-reported low NEB and 18 student musicians with self-reported high NEB completed a battery of tests that consisted of physiological measures, including auditory brainstem responses (ABRs) at three different stimulus rates (11.3 Hz, 51.3 Hz, and 81.3 Hz), and P300, and behavioral measures including conventional and extended high-frequency audiometry, consonant-vowel nucleus-consonant (CNC) word test and AzBio sentence test for assessing speech perception in noise abilities at -9, -6, -3, 0, and +3 dB signal to noise ratios (SNRs). The NEB was negatively associated with performance on the CNC test at all five SNRs. A negative association was found between NEB and performance on the AzBio test at 0 dB SNR. No effect of NEB was found on the amplitude and latency of P300 and the ABR wave I amplitude. More investigations of larger datasets with different NEB and longitudinal measurements are needed to investigate the influence of NEB on word recognition in noise and to understand the specific cognitive processes contributing to the impact of NEB on word recognition in noise.
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18
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Vasilkov V, Liberman MC, Maison SF. Isolating auditory-nerve contributions to electrocochleography by high-pass filtering: A better biomarker for cochlear nerve degeneration? JASA EXPRESS LETTERS 2023; 3:024401. [PMID: 36858988 PMCID: PMC9969351 DOI: 10.1121/10.0017328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 01/26/2023] [Indexed: 05/17/2023]
Abstract
In search of biomarkers for cochlear neural degeneration (CND) in electrocochleography from humans with normal thresholds, we high-pass and low-pass filtered the responses to separate contributions of auditory-nerve action potentials (N1) from hair-cell summating potentials (SP). The new N1 measure is better correlated with performance on difficult word-recognition tasks used as a proxy for CND. Furthermore, the paradoxical correlation between larger SPs and worse word scores, observed with classic electrocochleographic analysis, disappears with the new metric. Classic SP is simultaneous with and opposite in phase to an early neural contribution, and filtering separates the sources to eliminate this interference.
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Affiliation(s)
- Viacheslav Vasilkov
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear and Department of Otolaryngology -Head and Neck Surgery, Harvard Medical School, Boston, Massachussetts 02114, USA ; ;
| | - M Charles Liberman
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear and Department of Otolaryngology -Head and Neck Surgery, Harvard Medical School, Boston, Massachussetts 02114, USA ; ;
| | - Stéphane F Maison
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear and Department of Otolaryngology -Head and Neck Surgery, Harvard Medical School, Boston, Massachussetts 02114, USA ; ;
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19
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Le Prell CG, Clavier OH, Bao J. Noise-induced hearing disorders: Clinical and investigational tools. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:711. [PMID: 36732240 PMCID: PMC9889121 DOI: 10.1121/10.0017002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/05/2023] [Accepted: 01/09/2023] [Indexed: 06/18/2023]
Abstract
A series of articles discussing advanced diagnostics that can be used to assess noise injury and associated noise-induced hearing disorders (NIHD) was developed under the umbrella of the United States Department of Defense Hearing Center of Excellence Pharmaceutical Interventions for Hearing Loss working group. The overarching goals of the current series were to provide insight into (1) well-established and more recently developed metrics that are sensitive for detection of cochlear pathology or diagnosis of NIHD, and (2) the tools that are available for characterizing individual noise hazard as personal exposure will vary based on distance to the sound source and placement of hearing protection devices. In addition to discussing the utility of advanced diagnostics in patient care settings, the current articles discuss the selection of outcomes and end points that can be considered for use in clinical trials investigating hearing loss prevention and hearing rehabilitation.
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Affiliation(s)
- Colleen G Le Prell
- Department of Speech, Language, and Hearing Science, University of Texas at Dallas, Richardson, Texas 75080, USA
| | | | - Jianxin Bao
- Gateway Biotechnology Inc., St. Louis, Missouri 63132, USA
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20
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Gómez-Álvarez M, Johannesen PT, Coelho-de-Sousa SL, Klump GM, Lopez-Poveda EA. The Relative Contribution of Cochlear Synaptopathy and Reduced Inhibition to Age-Related Hearing Impairment for People With Normal Audiograms. Trends Hear 2023; 27:23312165231213191. [PMID: 37956654 PMCID: PMC10644751 DOI: 10.1177/23312165231213191] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 10/18/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023] Open
Abstract
Older people often show auditory temporal processing deficits and speech-in-noise intelligibility difficulties even when their audiogram is clinically normal. The causes of such problems remain unclear. Some studies have suggested that for people with normal audiograms, age-related hearing impairments may be due to a cognitive decline, while others have suggested that they may be caused by cochlear synaptopathy. Here, we explore an alternative hypothesis, namely that age-related hearing deficits are associated with decreased inhibition. For human adults (N = 30) selected to cover a reasonably wide age range (25-59 years), with normal audiograms and normal cognitive function, we measured speech reception thresholds in noise (SRTNs) for disyllabic words, gap detection thresholds (GDTs), and frequency modulation detection thresholds (FMDTs). We also measured the rate of growth (slope) of auditory brainstem response wave-I amplitude with increasing level as an indirect indicator of cochlear synaptopathy, and the interference inhibition score in the Stroop color and word test (SCWT) as a proxy for inhibition. As expected, performance in the auditory tasks worsened (SRTNs, GDTs, and FMDTs increased), and wave-I slope and SCWT inhibition scores decreased with ageing. Importantly, SRTNs, GDTs, and FMDTs were not related to wave-I slope but worsened with decreasing SCWT inhibition. Furthermore, after partialling out the effect of SCWT inhibition, age was no longer related to SRTNs or GDTs and became less strongly related to FMDTs. Altogether, results suggest that for people with normal audiograms, age-related deficits in auditory temporal processing and speech-in-noise intelligibility are mediated by decreased inhibition rather than cochlear synaptopathy.
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Affiliation(s)
- Marcelo Gómez-Álvarez
- Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca, Universidad de Salamanca, Salamanca, Spain
| | - Peter T. Johannesen
- Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca, Universidad de Salamanca, Salamanca, Spain
| | - Sónia L. Coelho-de-Sousa
- Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca, Universidad de Salamanca, Salamanca, Spain
| | - Georg M. Klump
- Department of Neuroscience and Cluster of Excellence “Hearing4all”, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
| | - Enrique A. Lopez-Poveda
- Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, Salamanca, Spain
- Instituto de Investigación Biomédica de Salamanca, Universidad de Salamanca, Salamanca, Spain
- Departamento de Cirugía, Facultad de Medicina, Universidad de Salamanca, Salamanca, Spain
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Trevino M, Zang A, Lobarinas E. The middle ear muscle reflex: Current and future role in assessing noise-induced cochlear damage. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:436. [PMID: 36732247 PMCID: PMC9867568 DOI: 10.1121/10.0016853] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 06/18/2023]
Abstract
The middle ear muscle reflex (MEMR) in humans is a bilateral contraction of the middle ear stapedial muscle in response to moderate-to-high intensity acoustic stimuli. Clinically, MEMR thresholds have been used for differential diagnosis of otopathologies for decades. More recently, changes in MEMR amplitude or threshold have been proposed as an assessment for noise-induced synaptopathy, a subclinical form of cochlear damage characterized by suprathreshold hearing problems that occur as a function of inner hair cell (IHC) synaptic loss, including hearing-in-noise deficits, tinnitus, and hyperacusis. In animal models, changes in wideband MEMR immittance have been correlated with noise-induced synaptopathy; however, studies in humans have shown more varied results. The discrepancies observed across studies could reflect the heterogeneity of synaptopathy in humans more than the effects of parametric differences or relative sensitivity of the measurement. Whereas the etiology and degree of synaptopathy can be carefully controlled in animal models, synaptopathy in humans likely stems from multiple etiologies and thus can vary greatly across the population. Here, we explore the evolving research evidence of the MEMR response in relation to subclinical noise-induced cochlear damage and the MEMR as an early correlate of suprathreshold deficits.
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Affiliation(s)
- Monica Trevino
- School of Behavioral and Brain Sciences, Department of Speech, Language and Hearing, The University of Texas at Dallas, Richardson, Texas 75080, USA
| | - Andie Zang
- School of Behavioral and Brain Sciences, Department of Speech, Language and Hearing, The University of Texas at Dallas, Richardson, Texas 75080, USA
| | - Edward Lobarinas
- School of Behavioral and Brain Sciences, Department of Speech, Language and Hearing, The University of Texas at Dallas, Richardson, Texas 75080, USA
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22
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Shehabi AM, Prendergast G, Guest H, Plack CJ. Binaural temporal coding and the middle ear muscle reflex in audiometrically normal young adults. Hear Res 2023; 427:108663. [PMID: 36502543 DOI: 10.1016/j.heares.2022.108663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 11/11/2022] [Accepted: 11/29/2022] [Indexed: 12/07/2022]
Abstract
Noise exposure may damage the synapses that connect inner hair cells with auditory nerve fibers, before outer hair cells are lost. In humans, this cochlear synaptopathy (CS) is thought to decrease the fidelity of peripheral auditory temporal coding. In the current study, the primary hypothesis was that higher middle ear muscle reflex (MEMR) thresholds, as a proxy measure of CS, would be associated with smaller values of the binaural intelligibility level difference (BILD). The BILD, which is a measure of binaural temporal coding, is defined here as the difference in thresholds between the diotic and the antiphasic versions of the digits in noise (DIN) test. This DIN BILD may control for factors unrelated to binaural temporal coding such as linguistic, central auditory, and cognitive factors. Fifty-six audiometrically normal adults (34 females) aged 18 - 30 were tested. The test battery included standard pure tone audiometry, tympanometry, MEMR using a 2 kHz elicitor and 226 Hz and 1 kHz probes, the Noise Exposure Structured Interview, forward digit span test, extended high frequency (EHF) audiometry, and diotic and antiphasic DIN tests. The study protocol was pre-registered prior to data collection. MEMR thresholds did not predict the DIN BILD. Secondary analyses showed no association between MEMR thresholds and the individual diotic and antiphasic DIN thresholds. Greater lifetime noise exposure was non-significantly associated with higher MEMR thresholds, larger DIN BILD values, and lower (better) antiphasic DIN thresholds, but not with diotic DIN thresholds, nor with EHF thresholds. EHF thresholds were associated with neither MEMR thresholds nor any of the DIN outcomes, including the DIN BILD. Results provide no evidence that young, audiometrically normal people incur CS with impacts on binaural temporal processing.
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Affiliation(s)
- Adnan M Shehabi
- Manchester Centre for Audiology and Deafness, University of Manchester, UK; Department of Audiology and Speech Therapy, Birzeit University, Palestine.
| | | | - Hannah Guest
- Manchester Centre for Audiology and Deafness, University of Manchester, UK
| | - Christopher J Plack
- Manchester Centre for Audiology and Deafness, University of Manchester, UK; Department of Psychology, Lancaster University, UK
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Casolani C, Harte JM, Epp B. Categorization of tinnitus listeners with a focus on cochlear synaptopathy. PLoS One 2022; 17:e0277023. [PMID: 36512555 PMCID: PMC9746990 DOI: 10.1371/journal.pone.0277023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 10/17/2022] [Indexed: 12/15/2022] Open
Abstract
Tinnitus is a complex and not yet fully understood phenomenon. Often the treatments provided are effective only for subgroups of sufferers. We are presently not able to predict benefit with the currently available diagnostic tools and analysis methods. Being able to identify and specifically treat sub-categories of tinnitus would help develop and implement more targeted treatments with higher success rate. In this study we use a clustering analysis based on 17 predictors to cluster an audiologically homogeneous group of normal hearing participants, both with and without tinnitus. The predictors have been chosen to be either tinnitus-specific measures or measures that are thought to be connected to cochlear synaptopathy. Our aim was to identify a subgroup of participants with characteristics consistent with the current hypothesized impact of cochlear synaptopathy. Our results show that this approach can separate the listeners into different clusters. But not in all cases could the tinnitus sufferers be separated from the control group. Another challenge is the use of categorical measures which seem to dominate the importance analysis of the factors. The study showed that data-driven clustering of a homogeneous listener group based on a mixed set of experimental outcome measures is a promising tool for tinnitus sub-typing, with the caveat that sample sizes might need to be sufficiently high, and higher than in the present study, to keep a meaningful sample size after clustering.
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Affiliation(s)
- Chiara Casolani
- Auditory Physics Group, Hearing Systems Section, Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
- Interacoustics Research Unit, Lyngby, Denmark
| | - James Michael Harte
- Interacoustics Research Unit, Lyngby, Denmark
- Eriksholm Research Centre, Snekkersten, Denmark
| | - Bastian Epp
- Auditory Physics Group, Hearing Systems Section, Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
- * E-mail:
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Chen J, Jennings SG. Temporal Envelope Coding of the Human Auditory Nerve Inferred from Electrocochleography: Comparison with Envelope Following Responses. J Assoc Res Otolaryngol 2022; 23:803-814. [PMID: 35948693 PMCID: PMC9789235 DOI: 10.1007/s10162-022-00865-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 07/12/2022] [Indexed: 01/06/2023] Open
Abstract
Neural coding of the slow amplitude fluctuations of sound (i.e., temporal envelope) is thought to be essential for speech understanding; however, such coding by the human auditory nerve is poorly understood. Here, neural coding of the temporal envelope by the human auditory nerve is inferred from measurements of the compound action potential in response to an amplitude modulated carrier (CAPENV) for modulation frequencies ranging from 20 to 1000 Hz. The envelope following response (EFR) was measured simultaneously with CAPENV from active electrodes placed on the high forehead and tympanic membrane, respectively. Results support the hypothesis that phase locking to higher modulation frequencies (> 80 Hz) will be stronger for CAPENV, compared to EFR, consistent with the upper-frequency limits of phase locking for auditory nerve fibers compared to auditory brainstem/cortex neurons. Future work is needed to determine the extent to which (1) CAPENV is a useful tool for studying how temporal processing of the auditory nerve is affected by aging, hearing loss, and noise-induced cochlear synaptopathy and (2) CAPENV reveals the relationship between auditory nerve temporal processing and perception of the temporal envelope.
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Affiliation(s)
- Jessica Chen
- Department of Communication Sciences and Disorders, The University of Utah, 390 South BEHS 1201, Salt Lake City, UT, USA
| | - Skyler G Jennings
- Department of Communication Sciences and Disorders, The University of Utah, 390 South BEHS 1201, Salt Lake City, UT, USA.
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Cross-species experiments reveal widespread cochlear neural damage in normal hearing. Commun Biol 2022; 5:733. [PMID: 35869142 PMCID: PMC9307777 DOI: 10.1038/s42003-022-03691-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/08/2022] [Indexed: 11/24/2022] Open
Abstract
Animal models suggest that cochlear afferent nerve endings may be more vulnerable than sensory hair cells to damage from acoustic overexposure and aging. Because neural degeneration without hair-cell loss cannot be detected in standard clinical audiometry, whether such damage occurs in humans is hotly debated. Here, we address this debate through co-ordinated experiments in at-risk humans and a wild-type chinchilla model. Cochlear neuropathy leads to large and sustained reductions of the wideband middle-ear muscle reflex in chinchillas. Analogously, human wideband reflex measures revealed distinct damage patterns in middle age, and in young individuals with histories of high acoustic exposure. Analysis of an independent large public dataset and additional measurements using clinical equipment corroborated the patterns revealed by our targeted cross-species experiments. Taken together, our results suggest that cochlear neural damage is widespread even in populations with clinically normal hearing. Cross-species experiments on chinchillas and at-risk humans suggest cochlear synaptopathy from noise exposure and aging are widespread even among individuals with clinically normal hearing status.
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Grinn SK, Le Prell CG. Evaluation of hidden hearing loss in normal-hearing firearm users. Front Neurosci 2022; 16:1005148. [PMID: 36389238 PMCID: PMC9644938 DOI: 10.3389/fnins.2022.1005148] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/07/2022] [Indexed: 04/05/2024] Open
Abstract
Some noise exposures resulting in temporary threshold shift (TTS) result in cochlear synaptopathy. The purpose of this retrospective study was to evaluate a human population that might be at risk for noise-induced cochlear synaptopathy (i.e., "hidden hearing loss"). Participants were firearm users who were (1) at-risk for prior audiometric noise-induced threshold shifts, given their history of firearm use, (2) likely to have experienced complete threshold recovery if any prior TTS had occurred, based on this study's normal-hearing inclusion criteria, and (3) not at-risk for significant age-related synaptopathic loss, based on this study's young-adult inclusion criteria. 70 participants (age 18-25 yr) were enrolled, including 33 firearm users experimental (EXP), and 37 non-firearm users control (CNTRL). All participants were required to exhibit audiometric thresholds ≤20 dB HL bilaterally, from 0.25 to 8 kHz. The study was designed to test the hypothesis that EXP participants would exhibit a reduced cochlear nerve response compared to CNTRL participants, despite normal-hearing sensitivity in both groups. No statistically significant group differences in auditory performance were detected between the CNTRL and EXP participants on standard audiom to etry, extended high-frequency audiometry, Words-in-Noise performance, distortion product otoacoustic emission, middle ear muscle reflex, or auditory brainstem response. Importantly, 91% of EXP participants reported that they wore hearing protection either "all the time" or "almost all the time" while using firearms. The data suggest that consistent use of hearing protection during firearm use can effectively protect cochlear and neural measures of auditory function, including suprathreshold responses. The current results do not exclude the possibility that neural pathology may be evident in firearm users with less consistent hearing protection use. However, firearm users with less consistent hearing protection use are also more likely to exhibit threshold elevation, among other cochlear deficits, thereby confounding the isolation of any potentially selective neural deficits. Taken together, it seems most likely that firearm users who consistently and correctly use hearing protection will exhibit preserved measures of cochlear and neural function, while firearm users who inconsistently and incorrectly use hearing protection are most likely to exhibit cochlear injury, rather than evidence of selective neural injury in the absence of cochlear injury.
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Affiliation(s)
- Sarah K. Grinn
- Department of Communication Sciences and Disorders, Central Michigan University, Mount Pleasant, MI, United States
| | - Colleen G. Le Prell
- Department of Speech, Language, and Hearing, University of Texas at Dallas, Dallas, TX, United States
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Lai J, Bidelman GM. Relative changes in the cochlear summating potentials to paired-clicks predict speech-in-noise perception and subjective hearing acuity. JASA EXPRESS LETTERS 2022; 2:102001. [PMID: 36319209 PMCID: PMC9987329 DOI: 10.1121/10.0014815] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Objective assays of human cochlear synaptopathy (CS) have been challenging to develop. It is suspected that relative summating potential (SP) changes are different in listeners with CS. In this proof-of-concept study, young, normal-hearing adults were recruited and assigned to a low/high-risk group for having CS based on their extended audiograms (9-16 kHz). SPs to paired-clicks with varying inter-click intervals isolated non-refractory receptor components of cochlear activity. Abrupt increases in SPs to paired- vs single-clicks were observed in high-risk listeners. Critically, exaggerated SPs predicted speech-in-noise and subjective hearing abilities, suggesting relative SP changes to rapid clicks might help identify putative synaptopathic listeners.
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Affiliation(s)
- Jesyin Lai
- Diagnostic Imaging Department, St. Jude Children's Research Hospital, Memphis, Tennessee 38152, USA
| | - Gavin M Bidelman
- Department of Speech, Language and Hearing Sciences, Indiana University, Bloomington, Indiana 47408, USA ,
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Abstract
PURPOSE OF REVIEW The purpose of this review is to offer a concise summary of current knowledge regarding hidden hearing loss (HHL) and to describe the variety of mechanisms that contribute to its development. We will also discuss the various diagnostic tools that are available as well as future directions. RECENT FINDINGS Hidden hearing loss often also called cochlear synaptopathy affects afferent synapses of the inner hair cells. This description is in contrast to traditional models of hearing loss, which predominantly affects auditory hair cells. In HHL, the synapses of nerve fibres with a slow spontaneous firing rate, which are crucial for locating sound in background noise, are severely impaired. In addition, recent research suggests that HHL may also be related to cochlear nerve demyelination. Noise exposure causes loss of myelin sheath thickness. Auditory brainstem response, envelope-following response and middle-ear muscle reflex are promising diagnostic tests, but they have yet to be validated in humans. SUMMARY Establishing diagnostic tools for cochlear synaptopathy in humans is important to better understand this patient population, predict the long-term outcomes and allow patients to take the necessary protective precautions.
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Kaf WA, Turntine M, Jamos A, Smurzynski J. Examining the Profile of Noise-Induced Cochlear Synaptopathy Using iPhone Health App Data and Cochlear and Brainstem Electrophysiological Responses to Fast Clicks Rates. Semin Hear 2022; 43:197-222. [PMID: 36313044 PMCID: PMC9605806 DOI: 10.1055/s-0042-1756164] [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: 11/07/2022] Open
Abstract
Little is known about objective classifying of noise exposure risk levels in personal listening device (PLD) users and electrophysiologic evidence of cochlear synaptopathy at very fast click rates. The aim of the study was to objectively classify noise exposure risk using iPhone Health app and identify signs of cochlear synaptopathy using behavioral and electrophysiologic measures. Thirty normal-hearing females (aged 18-26 years) were grouped based on their iPhone Health app's 6-month listening level and noise exposure data into low-risk and high-risk groups. They were assessed using a questionnaire, extended high-frequency (EHF) audiometry, QuickSIN test, distortion-product otoacoustic emission (DPOAE), and simultaneous recording of electrocochleography (ECochG) and auditory brainstem response (ABR) at three click rates (19.5/s, 97.7/s, 234.4/s). A series of ANOVAs and independent samples t -test were conducted for group comparison. Both groups had within-normal EHF hearing thresholds and DPOAEs. However, the high-risk participants were over twice as likely to suffer from tinnitus, had abnormally large summating potential to action potential amplitude and area ratios at fast rates, and had slightly smaller waves I and V amplitudes. The high-risk group demonstrated a profile of behavioral and objective signs of cochlear synaptopathy based on ECochG and ABR recordings at fast click rates. The findings in this study suggest that the iPhone Health app may be a useful tool for further investigation into cochlear synaptopathy in PLD users.
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Affiliation(s)
- Wafaa A. Kaf
- Department of Communication Sciences and Disorders, Missouri State University, Springfield, Missouri
| | - Madison Turntine
- Department of Communication Sciences and Disorders, Missouri State University, Springfield, Missouri
| | - Abdullah Jamos
- Department of Communication Sciences and Disorders, Missouri State University, Springfield, Missouri
| | - Jacek Smurzynski
- Department of Audiology and Speech-Language Pathology, East Tennessee State University, Johnson City, Tennessee
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Pinsonnault-Skvarenina A, Moïn-Darbari K, Zhao W, Zhang M, Qiu W, Fuente A. No effect of occupational noise exposure on auditory brainstem response and speech perception in noise. Front Neurosci 2022; 16:915211. [PMID: 35937884 PMCID: PMC9354017 DOI: 10.3389/fnins.2022.915211] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 07/05/2022] [Indexed: 11/13/2022] Open
Abstract
The primary aim of this study was to investigate whether auditory brainstem response (ABR) and speech perception in noise (SPiN) were associated with occupational noise exposure in normal hearing young factory workers. Forty young adults occupationally exposed to noise and 40 non-exposed young adults (control group) from Zhejiang province in China were selected. All participants presented with normal hearing thresholds and distortion product otoacoustic emissions. Participants were evaluated with the Mandarin Bamford-Kowal-Bench (BKB) test and ABR. The latter was obtained for click stimulus at 50, 60, 70, 80, and 90 dBnHL. Peak-to-trough amplitudes and latencies for waves I and V were obtained. The ABR wave I amplitude, the wave I/V amplitude ratio, the slope of the wave I amplitude growth as a function of stimulus intensity (AMP-ISlope), and the wave V latency shift with ipsilateral noise (LAT-VSlope) were used as ABR outcomes. Finally, equivalent continuous average sound pressure level normalized to 8 h (LAeq.8h) and cumulative noise exposure (CNE) were obtained for noise-exposed participants. No significant differences between groups were found for any ABR outcomes. Noise-exposed participants exhibited worse BKB scores than control group participants. A multivariate regression model showed that 23.3% of the variance in BKB scores was explained by group category (exposed vs. non-exposed) and hearing thresholds. However, since none of the ABR outcomes exploring cochlear synaptopathy were associated with noise exposure, we cannot conclude that cochlear synaptopathy was the contributing factor for the differences between groups for BKB scores. Factors that go beyond sensory processing may explain such results, especially given socio-economic differences between the noise-exposed and control groups. We conclude that in this sample of participants, occupational noise exposure was not associated with signs of cochlear synaptopathy as measured by ABR and BKB.
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Affiliation(s)
- Alexis Pinsonnault-Skvarenina
- École d’Orthophonie et d’Audiologie, Faculté de Médecine, Université de Montréal, Montréal, QC, Canada
- Centre de Recherche Interdisciplinaire en Réadaptation du Montréal Métropolitain – CIUSSS du Centre-Sud-de-l’Île-de-Montréal, Montréal, QC, Canada
- Centre for Interdisciplinary Research in Music Media and Technology, McGill University, Montréal, QC, Canada
| | - Karina Moïn-Darbari
- École d’Orthophonie et d’Audiologie, Faculté de Médecine, Université de Montréal, Montréal, QC, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal – CIUSSS du Centre-Sud-de-l’ÎIe-de-Montréal, Montréal, QC, Canada
| | - Wulan Zhao
- Zhejiang Chinese Medical University, Hangzhou, China
| | - Meibian Zhang
- National Institute of Occupational Health and Poison Control, Beijing, China
| | - Wei Qiu
- Auditory Research Laboratory, State University of New York at Plattsburgh, Plattsburgh, NY, United States
| | - Adrian Fuente
- École d’Orthophonie et d’Audiologie, Faculté de Médecine, Université de Montréal, Montréal, QC, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal – CIUSSS du Centre-Sud-de-l’ÎIe-de-Montréal, Montréal, QC, Canada
- *Correspondence: Adrian Fuente,
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Jahn KN. Clinical and investigational tools for monitoring noise-induced hyperacusis. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 152:553. [PMID: 35931527 PMCID: PMC9448410 DOI: 10.1121/10.0012684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Hyperacusis is a recognized perceptual consequence of acoustic overexposure that can lead to debilitating psychosocial effects. Despite the profound impact of hyperacusis on quality of life, clinicians and researchers lack objective biomarkers and standardized protocols for its assessment. Outcomes of conventional audiologic tests are highly variable in the hyperacusis population and do not adequately capture the multifaceted nature of the condition on an individual level. This presents challenges for the differential diagnosis of hyperacusis, its clinical surveillance, and evaluation of new treatment options. Multiple behavioral and objective assays are emerging as contenders for inclusion in hyperacusis assessment protocols but most still await rigorous validation. There remains a pressing need to develop tools to quantify common nonauditory symptoms, including annoyance, fear, and pain. This review describes the current literature on clinical and investigational tools that have been used to diagnose and monitor hyperacusis, as well as those that hold promise for inclusion in future trials.
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Affiliation(s)
- Kelly N Jahn
- Department of Speech, Language, and Hearing, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, Texas 75080, USA
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32
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Jain S, Narne VK, Nataraja NP, Madhukesh S, Kumar K, Moore BCJ. The effect of age and hearing sensitivity at frequencies above 8 kHz on auditory stream segregation and speech perception. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 152:716. [PMID: 35931505 DOI: 10.1121/10.0012917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 07/07/2022] [Indexed: 06/06/2023]
Abstract
The effects of age and mild hearing loss over the extended high-frequency (EHF) range from 9000 to 16 000 Hz on speech perception and auditory stream segregation were assessed using four groups: (1) young with normal hearing threshold levels (HTLs) over both the conventional and EHF range; (2) older with audiograms matched to those for group 1; (3) young with normal HTLs over the conventional frequency range and elevated HTLs over the EHF range; (4) older with audiograms matched to those for group 3. For speech in quiet, speech recognition thresholds and speech identification scores did not differ significantly across groups. For monosyllables in noise, both greater age and hearing loss over the EHF range adversely affected performance, but the effect of age was much larger than the effect of hearing status. Stream segregation was assessed using a rapid sequence of vowel stimuli differing in fundamental frequency (F0). Larger differences in F0 were required for stream segregation for the two groups with impaired hearing in the EHF range, but there was no significant effect of age. It is argued that impaired hearing in the EHF range is associated with impaired auditory function at lower frequencies, despite normal audiometric thresholds at those frequencies.
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Affiliation(s)
- Saransh Jain
- All India Institute of Speech and Hearing, University of Mysore, Mysuru-570006 (Kar.), India
| | - Vijaya Kumar Narne
- Department of Medical Rehabilitation Sciences, College of Applied Medical Sciences, King Khalid University, Abha 61481, Saudi Arabia
| | - N P Nataraja
- JSS Institute of Speech and Hearing, University of Mysore, Mysuru-570004 (Kar.), India
| | - Sanjana Madhukesh
- Department of Speech and Hearing, Manipal College of Health Professionals, Manipal-576104 (Kar.), India
| | - Kruthika Kumar
- District Disabled Rehabilitation Centre, Chikmagalur-577126 (Kar.), India
| | - Brian C J Moore
- Cambridge Hearing Group, Department of Psychology, University of Cambridge, Cambridge, CB2 3EB, United Kingdom
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33
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Grant KJ, Parthasarathy A, Vasilkov V, Caswell-Midwinter B, Freitas ME, de Gruttola V, Polley DB, Liberman MC, Maison SF. Predicting neural deficits in sensorineural hearing loss from word recognition scores. Sci Rep 2022; 12:8929. [PMID: 35739134 PMCID: PMC9226113 DOI: 10.1038/s41598-022-13023-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/19/2022] [Indexed: 12/28/2022] Open
Abstract
The current gold standard of clinical hearing assessment includes a pure-tone audiogram combined with a word recognition task. This retrospective study tests the hypothesis that deficits in word recognition that cannot be explained by loss in audibility or cognition may reflect underlying cochlear nerve degeneration (CND). We collected the audiological data of nearly 96,000 ears from patients with normal hearing, conductive hearing loss (CHL) and a variety of sensorineural etiologies including (1) age-related hearing loss (ARHL); (2) neuropathy related to vestibular schwannoma or neurofibromatosis of type 2; (3) Ménière’s disease; (4) sudden sensorineural hearing loss (SSNHL), (5) exposure to ototoxic drugs (carboplatin and/or cisplatin, vancomycin or gentamicin) or (6) noise damage including those with a 4-kHz “noise notch” or reporting occupational or recreational noise exposure. Word recognition was scored using CID W-22 monosyllabic word lists. The Articulation Index was used to predict the speech intelligibility curve using a transfer function for CID W-22. The level at which maximal intelligibility was predicted was used as presentation level (70 dB HL minimum). Word scores decreased dramatically with age and thresholds in all groups with SNHL etiologies, but relatively little in the conductive hearing loss group. Discrepancies between measured and predicted word scores were largest in patients with neuropathy, Ménière’s disease and SSNHL, intermediate in the noise-damage and ototoxic drug groups, and smallest in the ARHL group. In the CHL group, the measured and predicted word scores were very similar. Since word-score predictions assume that audiometric losses can be compensated by increasing stimulus level, their accuracy in predicting word score for CHL patients is unsurprising. The lack of a strong age effect on word scores in CHL shows that cognitive decline is not a major factor in this test. Amongst the possible contributions to word score discrepancies, CND is a prime candidate: it should worsen intelligibility without affecting thresholds and has been documented in human temporal bones with SNHL. Comparing the audiological trends observed here with the existing histopathological literature supports the notion that word score discrepancies may be a useful CND metric.
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Affiliation(s)
- Kelsie J Grant
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA
| | - Aravindakshan Parthasarathy
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA.,Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston, MA, USA.,Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA, USA
| | - Viacheslav Vasilkov
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA.,Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston, MA, USA
| | - Benjamin Caswell-Midwinter
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA.,Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston, MA, USA
| | - Maria E Freitas
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA
| | - Victor de Gruttola
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Daniel B Polley
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA.,Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston, MA, USA
| | - M Charles Liberman
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA.,Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston, MA, USA
| | - Stéphane F Maison
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, MA, 02114-3096, USA. .,Department of Otolaryngology - Head and Neck Surgery, Harvard Medical School, Boston, MA, USA.
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Shehabi AM, Prendergast G, Plack CJ. The Relative and Combined Effects of Noise Exposure and Aging on Auditory Peripheral Neural Deafferentation: A Narrative Review. Front Aging Neurosci 2022; 14:877588. [PMID: 35813954 PMCID: PMC9260498 DOI: 10.3389/fnagi.2022.877588] [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: 02/16/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Animal studies have shown that noise exposure and aging cause a reduction in the number of synapses between low and medium spontaneous rate auditory nerve fibers and inner hair cells before outer hair cell deterioration. This noise-induced and age-related cochlear synaptopathy (CS) is hypothesized to compromise speech recognition at moderate-to-high suprathreshold levels in humans. This paper evaluates the evidence on the relative and combined effects of noise exposure and aging on CS, in both animals and humans, using histopathological and proxy measures. In animal studies, noise exposure seems to result in a higher proportion of CS (up to 70% synapse loss) compared to aging (up to 48% synapse loss). Following noise exposure, older animals, depending on their species, seem to either exhibit significant or little further synapse loss compared to their younger counterparts. In humans, temporal bone studies suggest a possible age- and noise-related auditory nerve fiber loss. Based on the animal data obtained from different species, we predict that noise exposure may accelerate age-related CS to at least some extent in humans. In animals, noise-induced and age-related CS in separation have been consistently associated with a decreased amplitude of wave 1 of the auditory brainstem response, reduced middle ear muscle reflex strength, and degraded temporal processing as demonstrated by lower amplitudes of the envelope following response. In humans, the individual effects of noise exposure and aging do not seem to translate clearly into deficits in electrophysiological, middle ear muscle reflex, and behavioral measures of CS. Moreover, the evidence on the combined effects of noise exposure and aging on peripheral neural deafferentation in humans using electrophysiological and behavioral measures is even more sparse and inconclusive. Further research is necessary to establish the individual and combined effects of CS in humans using temporal bone, objective, and behavioral measures.
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Affiliation(s)
- Adnan M. Shehabi
- Manchester Centre for Audiology and Deafness, University of Manchester, Manchester, United Kingdom
- Department of Audiology and Speech Therapy, Birzeit University, Birzeit, Palestine
| | - Garreth Prendergast
- Manchester Centre for Audiology and Deafness, University of Manchester, Manchester, United Kingdom
| | - Christopher J. Plack
- Manchester Centre for Audiology and Deafness, University of Manchester, Manchester, United Kingdom
- Department of Psychology, Lancaster University, Lancaster, United Kingdom
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Le Prell CG. Prevention of Noise-Induced Hearing Loss Using Investigational Medicines for the Inner Ear: Previous Trial Outcomes Should Inform Future Trial Design. Antioxid Redox Signal 2022; 36:1171-1202. [PMID: 34346254 PMCID: PMC9221155 DOI: 10.1089/ars.2021.0166] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 07/25/2021] [Indexed: 11/13/2022]
Abstract
Significance: Noise-induced hearing loss (NIHL) is an important public health issue resulting in decreased quality of life for affected individuals, and significant costs to employers and governmental agencies. Recent Advances: Advances in the mechanistic understanding of NIHL have prompted a growing number of proposed, in-progress, and completed clinical trials for possible protections against NIHL via antioxidants and other drug agents. Thirty-one clinical trials evaluating prevention of either temporary or permanent NIHL were identified and are reviewed. Critical Issues: This review revealed little consistency in the noise-exposed populations in which drugs are evaluated or the primary outcomes used to measure NIHL prevention. Changes in pure-tone thresholds were the most common primary outcomes; specific threshold metrics included both average hearing loss and incidence of significant hearing loss. Changes in otoacoustic emission (OAE) amplitude were relatively common secondary outcomes. Extended high-frequency (EHF) hearing and speech-in-noise perception are commonly adversely affected by noise exposure but are not consistently included in clinical trials assessing prevention of NIHL. Future Directions: Multiple criteria are available for monitoring NIHL, but the specific criterion to be used to define clinically significant otoprotection remains a topic of discussion. Audiogram-based primary outcome measures can be combined with secondary outcomes, including OAE amplitude, EHF hearing, speech-in-noise testing, tinnitus surveys, and patient-reported outcomes. Standardization of test protocols for the above primary and secondary outcomes, and associated reporting criterion for each, would facilitate clinical trial design and comparison of results across investigational drug agents. Antioxid. Redox Signal. 36, 1171-1202.
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Affiliation(s)
- Colleen G. Le Prell
- Department of Speech, Language, and Hearing Science, University of Texas at Dallas, Richardson, Texas, USA
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36
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Jahn KN, Hancock KE, Maison SF, Polley DB. Estimated cochlear neural degeneration is associated with loudness hypersensitivity in individuals with normal audiograms. JASA EXPRESS LETTERS 2022; 2:064403. [PMID: 35719240 PMCID: PMC9199082 DOI: 10.1121/10.0011694] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/25/2022] [Indexed: 05/27/2023]
Abstract
In animal models, cochlear neural degeneration (CND) is associated with excess central gain and hyperacusis, but a compelling link between reduced cochlear neural inputs and heightened loudness perception in humans remains elusive. The present study examined whether greater estimated cochlear neural degeneration (eCND) in human participants with normal hearing thresholds is associated with heightened loudness perception and sound aversion. Results demonstrated that loudness perception was heightened in ears with greater eCND and in subjects who self-report loudness aversion via a hyperacusis questionnaire. These findings suggest that CND may be a potential trigger for loudness hypersensitivity.
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Affiliation(s)
- Kelly N Jahn
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts 02114, USA , , ,
| | - Kenneth E Hancock
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts 02114, USA , , ,
| | - Stéphane F Maison
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts 02114, USA , , ,
| | - Daniel B Polley
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston, Massachusetts 02114, USA , , ,
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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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Harris KC, Bao J. Optimizing non-invasive functional markers for cochlear deafferentation based on electrocochleography and auditory brainstem responses. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 151:2802. [PMID: 35461487 PMCID: PMC9034896 DOI: 10.1121/10.0010317] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/22/2022] [Accepted: 04/08/2022] [Indexed: 06/14/2023]
Abstract
Accumulating evidence suggests that cochlear deafferentation may contribute to suprathreshold deficits observed with or without elevated hearing thresholds, and can lead to accelerated age-related hearing loss. Currently there are no clinical diagnostic tools to detect human cochlear deafferentation in vivo. Preclinical studies using a combination of electrophysiological and post-mortem histological methods clearly demonstrate cochlear deafferentation including myelination loss, mitochondrial damages in spiral ganglion neurons (SGNs), and synaptic loss between inner hair cells and SGNs. Since clinical diagnosis of human cochlear deafferentation cannot include post-mortem histological quantification, various attempts based on functional measurements have been made to detect cochlear deafferentation. So far, those efforts have led to inconclusive results. Two major obstacles to the development of in vivo clinical diagnostics include a lack of standardized methods to validate new approaches and characterize the normative range of repeated measurements. In this overview, we examine strategies from previous studies to detect cochlear deafferentation from electrocochleography and auditory brainstem responses. We then summarize possible approaches to improve these non-invasive functional methods for detecting cochlear deafferentation with a focus on cochlear synaptopathy. We identify conceptual approaches that should be tested to associate unique electrophysiological features with cochlear deafferentation.
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Affiliation(s)
- Kelly C Harris
- Department of Otolaryngology, Head & Neck Surgery, Medical University of South Carolina, 135 Rutledge Avenue, MSC 550, Charleston, South Carolina 29425, USA
| | - Jianxin Bao
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio 44272, USA
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Lutz BT, Hutson KA, Trecca EMC, Hamby M, Fitzpatrick DC. Neural Contributions to the Cochlear Summating Potential: Spiking and Dendritic Components. J Assoc Res Otolaryngol 2022; 23:351-363. [PMID: 35254541 DOI: 10.1007/s10162-022-00842-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/21/2022] [Indexed: 11/30/2022] Open
Abstract
Using electrocochleography, the summating potential (SP) is a deflection from baseline to tones and an early rise in the response to clicks. Here, we use normal hearing gerbils and gerbils with outer hair cells removed with a combination of furosemide and kanamycin to investigate cellular origins of the SP. Round window electrocochleography to tones and clicks was performed before and after application of tetrodotoxin to prevent action potentials, and then again after kainic acid to prevent generation of an EPSP. With appropriate subtractions of the response curves from the different conditions, the contributions to the SP from outer hair cells, inner hair cell, and neural "spiking" and "dendritic" responses were isolated. Like hair cells, the spiking and dendritic components had opposite polarities to tones - the dendritic component had negative polarity and the spiking component had positive polarity. The magnitude of the spiking component was larger than the dendritic across frequencies and intensities. The onset to tones and to clicks followed a similar sequence; the outer hair cells responded first, then inner hair cells, then the dendritic component, and then the compound action potential of the spiking response. These results show the sources of the SP include at least the four components studied, and that these have a mixture of polarities and magnitudes that vary across frequency and intensity. Thus, multiple possible interactions must be considered when interpreting the SP for clinical uses.
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Affiliation(s)
- Brendan T Lutz
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA
| | - Kendall A Hutson
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA
| | - Eleonora M C Trecca
- IRCCS Casa Sollievo Della Sofferenza, Department of Maxillofacial Surgery and Otolaryngology, San Giovanni Rotondo (Foggia), Italy.,University Hospital of Foggia, Department of Otolaryngology- Head and Neck Surgery, Foggia, Italy
| | - Meredith Hamby
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA
| | - Douglas C Fitzpatrick
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA.
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Bramhall NF, Reavis KM, Feeney MP, Kampel SD. The Impacts of Noise Exposure on the Middle Ear Muscle Reflex in a Veteran Population. Am J Audiol 2022; 31:126-142. [PMID: 35050699 PMCID: PMC10831927 DOI: 10.1044/2021_aja-21-00133] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
PURPOSE Human studies of noise-induced cochlear synaptopathy using physiological indicators identified in animal models (auditory brainstem response [ABR] Wave I amplitude, envelope following response [EFR], and middle ear muscle reflex [MEMR]) have yielded mixed findings. Differences in the population studied may have contributed to the differing results. For example, due to differences in the intensity level of the noise exposure, noise-induced synaptopathy may be easier to detect in a military Veteran population than in populations with recreational noise exposure. We previously demonstrated a reduction in ABR Wave I amplitude and EFR magnitude for young Veterans with normal audiograms reporting high levels of noise exposure compared to non-Veteran controls. In this article, we expand on the previous analysis in the same population to determine if MEMR magnitude is similarly reduced. METHOD Contralateral MEMR growth functions were obtained in 92 young Veterans and non-Veterans with normal audiograms, and the relationship between noise exposure history and MEMR magnitude was assessed. Associations between MEMR magnitude and distortion product otoacoustic emission, EFR, and ABR measurements collected in the same sample were also evaluated. RESULTS The results of the statistical analysis, although not conventionally statistically significant, suggest a reduction in mean MEMR magnitude for Veterans reporting high noise exposure compared with non-Veteran controls. In addition, the MEMR appears relatively insensitive to subclinical outer hair cell dysfunction, as measured by distortion product otoacoustic emissions, and is not well correlated with ABR and EFR measurements. CONCLUSIONS When combined with our previous ABR and EFR findings in the same population, these results suggest that noise-induced synaptopathy occurs in humans. In addition, the findings indicate that the MEMR may be a good candidate for noninvasive diagnosis of cochlear synaptopathy/deafferentation and that the MEMR may reflect the integrity of different neural populations than the ABR and EFR. SUPPLEMENTAL MATERIAL https://doi.org/10.23641/asha.18665645.
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Affiliation(s)
- Naomi F Bramhall
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
- Department of Otolaryngology - Head & Neck Surgery, Oregon Health & Science University, Portland
| | - Kelly M Reavis
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
| | - M Patrick Feeney
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
- Department of Otolaryngology - Head & Neck Surgery, Oregon Health & Science University, Portland
| | - Sean D Kampel
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
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Sonstrom Malowski K, Gollihugh LH, Malyuk H, Le Prell CG. Auditory changes following firearm noise exposure, a review. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 151:1769. [PMID: 35364940 DOI: 10.1121/10.0009675] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/10/2022] [Indexed: 06/14/2023]
Abstract
Firearms produce peak sound pressure levels (peak SPL) between ∼130 and 175 dB peak SPL, creating significant risk of noise-induced hearing loss (NIHL) in those exposed to firearm noise during occupational, recreational, and/or military operations. Noise-induced tinnitus and hearing loss are common in military service members, public safety officers, and hunters/shooters. Given the significant risk of NIHL due to firearm and other noise sources, there is an interest in, and demand for, interventions to prevent and/or treat NIHL in high-risk populations. However, research and clinical trial designs assessing NIHL prevention have varied due to inconsistent data from the literature, specifically with end point definitions, study protocols, and assessment methodologies. This article presents a scoping review of the literature pertaining to auditory changes following firearm noise exposure. Meta-analysis was not possible due to heterogeneity of the study designs. Recommendations regarding audiologic test approach and monitoring of populations at risk for NIHL are presented based on critical review of the existing literature.
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Affiliation(s)
| | - Lindsay H Gollihugh
- School of Speech-Language Pathology and Audiology, The University of Akron, Akron, Ohio 44325, USA
| | - Heather Malyuk
- School of Speech-Language Pathology and Audiology, The University of Akron, Akron, Ohio 44325, USA
| | - Colleen G Le Prell
- Department of Speech, Language, and Hearing, The University of Texas at Dallas, Richardson, Texas 75080, USA
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Evidence for Loss of Activity in Low-Spontaneous-Rate Auditory Nerve Fibers of Older Adults. J Assoc Res Otolaryngol 2022; 23:273-284. [PMID: 35020090 PMCID: PMC8964899 DOI: 10.1007/s10162-021-00827-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 11/29/2021] [Indexed: 10/19/2022] Open
Abstract
Auditory function declines with age, as evidenced by communication difficulties in challenging listening environments for older adults. Declining auditory function may arise, in part, from an age-related loss and/or inactivity of low-spontaneous-rate (SR) auditory nerve (AN) fibers, a subgroup of neurons important for suprathreshold processing. Compared to high-SR fibers, low-SR fibers take longer to recover from prior stimulation. Taking advantage of this difference, the forward-masked recovery function paradigm estimates the relative proportions of low- and high-SR fibers in the AN by quantifying the time needed for AN responses to recover from prior stimulation (ΔTrecovery). Due to the slower recovery of low-SR fibers, ANs that need more time to fully recover (longer ΔTrecovery) are estimated to have a larger proportion of low-SR fibers than ANs that need less time (shorter ΔTrecovery). To test the hypothesis that low-SR fiber activity is reduced in older humans, the current study assessed recovery functions in 32 older and 16 younger adults using the compound action potential. Results show that ΔTrecovery is shorter for older adults than for younger adults, consistent with a theorized age-related loss and/or inactivity of low-SR fibers. ΔTrecovery did not differ between individuals with and without a prior history of noise exposure as assessed by self-report. This study is the first to successfully assess forward-masked recovery functions in both younger and older adults and provides important insights into the structural and functional changes occurring in the AN with increasing age.
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Cutting Through the Noise: Noise-Induced Cochlear Synaptopathy and Individual Differences in Speech Understanding Among Listeners With Normal Audiograms. Ear Hear 2022; 43:9-22. [PMID: 34751676 PMCID: PMC8712363 DOI: 10.1097/aud.0000000000001147] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Following a conversation in a crowded restaurant or at a lively party poses immense perceptual challenges for some individuals with normal hearing thresholds. A number of studies have investigated whether noise-induced cochlear synaptopathy (CS; damage to the synapses between cochlear hair cells and the auditory nerve following noise exposure that does not permanently elevate hearing thresholds) contributes to this difficulty. A few studies have observed correlations between proxies of noise-induced CS and speech perception in difficult listening conditions, but many have found no evidence of a relationship. To understand these mixed results, we reviewed previous studies that have examined noise-induced CS and performance on speech perception tasks in adverse listening conditions in adults with normal or near-normal hearing thresholds. Our review suggests that superficially similar speech perception paradigms used in previous investigations actually placed very different demands on sensory, perceptual, and cognitive processing. Speech perception tests that use low signal-to-noise ratios and maximize the importance of fine sensory details- specifically by using test stimuli for which lexical, syntactic, and semantic cues do not contribute to performance-are more likely to show a relationship to estimated CS levels. Thus, the current controversy as to whether or not noise-induced CS contributes to individual differences in speech perception under challenging listening conditions may be due in part to the fact that many of the speech perception tasks used in past studies are relatively insensitive to CS-induced deficits.
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44
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Buran BN, McMillan GP, Keshishzadeh S, Verhulst S, Bramhall NF. Predicting synapse counts in living humans by combining computational models with auditory physiology. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 151:561. [PMID: 35105019 PMCID: PMC8800592 DOI: 10.1121/10.0009238] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 12/09/2021] [Accepted: 12/13/2021] [Indexed: 05/28/2023]
Abstract
Aging, noise exposure, and ototoxic medications lead to cochlear synapse loss in animal models. As cochlear function is highly conserved across mammalian species, synaptopathy likely occurs in humans as well. Synaptopathy is predicted to result in perceptual deficits including tinnitus, hyperacusis, and difficulty understanding speech-in-noise. The lack of a method for diagnosing synaptopathy in living humans hinders studies designed to determine if noise-induced synaptopathy occurs in humans, identify the perceptual consequences of synaptopathy, or test potential drug treatments. Several physiological measures are sensitive to synaptopathy in animal models including auditory brainstem response (ABR) wave I amplitude. However, it is unclear how to translate these measures to synaptopathy diagnosis in humans. This work demonstrates how a human computational model of the auditory periphery, which can predict ABR waveforms and distortion product otoacoustic emissions (DPOAEs), can be used to predict synaptic loss in individual human participants based on their measured DPOAE levels and ABR wave I amplitudes. Lower predicted synapse numbers were associated with advancing age, higher noise exposure history, increased likelihood of tinnitus, and poorer speech-in-noise perception. These findings demonstrate the utility of this modeling approach in predicting synapse counts from physiological data in individual human subjects.
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Affiliation(s)
- Brad N Buran
- Oregon Hearing Research Center (OHRC), Department of Otolaryngology-Head & Neck Surgery, Oregon Health & Science University, Portland, Oregon, USA
| | - Garnett P McMillan
- Veterans Affairs (VA) Rehabilitation Research & Development Service (RR&D) National Center for Rehabilitative Auditory Research (NCRAR), VA Portland Health Care System, Portland, Oregon, USA
| | - Sarineh Keshishzadeh
- Hearing Technology @ WAVES, Department of Information Technology, Ghent University, Belgium
| | - Sarah Verhulst
- Hearing Technology @ WAVES, Department of Information Technology, Ghent University, Belgium
| | - Naomi F Bramhall
- Veterans Affairs (VA) Rehabilitation Research & Development Service (RR&D) National Center for Rehabilitative Auditory Research (NCRAR), VA Portland Health Care System, Portland, Oregon, USA
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Carcagno S, Plack CJ. Relations between speech-reception, psychophysical temporal processing, and subcortical electrophysiological measures of auditory function in humans. Hear Res 2022; 417:108456. [PMID: 35149333 PMCID: PMC8935383 DOI: 10.1016/j.heares.2022.108456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 01/05/2022] [Accepted: 01/27/2022] [Indexed: 11/04/2022]
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Current topics in hearing research: Deafferentation and threshold independent hearing loss. Hear Res 2021; 419:108408. [PMID: 34955321 DOI: 10.1016/j.heares.2021.108408] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/28/2021] [Accepted: 11/30/2021] [Indexed: 11/20/2022]
Abstract
Hearing research findings in recent years have begun to change how we think about hearing loss and how we consider the risk of auditory damage from noise exposure. These findings include evidence of noise-induced cochlear damage in the absence of corresponding permanent threshold elevation or evidence of hair cell loss. Animal studies in several species have shown that noise exposures that produce robust but only temporary threshold shifts can permanently damage inner hair cell synaptic ribbons. This type of synaptic degeneration has also been shown to occur as a result of aging in animals and humans. The emergence of these data has motivated a number of clinical studies aimed at identifying the perceptual correlates associated with synaptopathy. The deficits believed to arise from synaptopathy include poorer hearing in background noise, tinnitus and hyperacusis (loudness intolerance). However, the findings from human studies have been mixed. Key questions remain as to whether synaptopathy reliably produces suprathreshold perceptual deficits or whether it serves as an early indicator of auditory damage with suprathreshold deficits emerging later as a function of further cochlear damage. Here, we provide an overview of both human and animal studies that explore the relationship among inner hair cell damage, including loss of afferent synapses, auditory thresholds, and suprathreshold measures of hearing.
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Bramhall NF. Use of the auditory brainstem response for assessment of cochlear synaptopathy in humans. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:4440. [PMID: 34972291 PMCID: PMC10880747 DOI: 10.1121/10.0007484] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 11/07/2021] [Indexed: 06/14/2023]
Abstract
Although clinical use of the auditory brainstem response (ABR) to detect retrocochlear disorders has been largely replaced by imaging in recent years, the discovery of cochlear synaptopathy has thrown this foundational measure of auditory function back into the spotlight. Whereas modern imaging now allows for the noninvasive detection of vestibular schwannomas, imaging technology is not currently capable of detecting cochlear synaptopathy, the loss of the synaptic connections between the inner hair cells and afferent auditory nerve fibers. However, animal models indicate that the amplitude of the first wave of the ABR, a far-field evoked potential generated by the synchronous firing of auditory nerve fibers, is highly correlated with synaptic integrity. This has led to many studies investigating the use of the ABR as a metric of synaptopathy in humans. However, these studies have yielded mixed results, leading to a lack of consensus about the utility of the ABR as an indicator of synaptopathy. This review summarizes the animal and human studies that have investigated the ABR as a measure of cochlear synaptic function, discusses factors that may have contributed to the mixed findings and the lessons learned, and provides recommendations for future use of this metric in the research and clinical settings.
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Affiliation(s)
- Naomi F Bramhall
- Veterans Affairs (VA) Rehabilitation Research & Development Service (RR&D) National Center for Rehabilitative Auditory Research (NCRAR), VA Portland Health Care System Portland, Oregon 97239, USA
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Settibhaktini H, Heinz MG, Chintanpalli A. Modeling the effects of age and hearing loss on concurrent vowel scores. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:3581. [PMID: 34852572 PMCID: PMC8594952 DOI: 10.1121/10.0007046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 10/09/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
A difference in fundamental frequency (F0) between two vowels is an important segregation cue prior to identifying concurrent vowels. To understand the effects of this cue on identification due to age and hearing loss, Chintanpalli, Ahlstrom, and Dubno [(2016). J. Acoust. Soc. Am. 140, 4142-4153] collected concurrent vowel scores across F0 differences for younger adults with normal hearing (YNH), older adults with normal hearing (ONH), and older adults with hearing loss (OHI). The current modeling study predicts these concurrent vowel scores to understand age and hearing loss effects. The YNH model cascaded the temporal responses of an auditory-nerve model from Bruce, Efrani, and Zilany [(2018). Hear. Res. 360, 40-45] with a modified F0-guided segregation algorithm from Meddis and Hewitt [(1992). J. Acoust. Soc. Am. 91, 233-245] to predict concurrent vowel scores. The ONH model included endocochlear-potential loss, while the OHI model also included hair cell damage; however, both models incorporated cochlear synaptopathy, with a larger effect for OHI. Compared with the YNH model, concurrent vowel scores were reduced across F0 differences for ONH and OHI models, with the lowest scores for OHI. These patterns successfully captured the age and hearing loss effects in the concurrent-vowel data. The predictions suggest that the inability to utilize an F0-guided segregation cue, resulting from peripheral changes, may reduce scores for ONH and OHI listeners.
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Affiliation(s)
- Harshavardhan Settibhaktini
- Department of Electrical and Electronics Engineering, Birla Institute of Technology and Science, Pilani Campus, Vidya Vihar, Pilani, Rajasthan 333031, India
| | - Michael G Heinz
- Department of Speech, Language and Hearing Sciences, and Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907-2028, USA
| | - Ananthakrishna Chintanpalli
- Department of Electrical and Electronics Engineering, Birla Institute of Technology and Science, Pilani Campus, Vidya Vihar, Pilani, Rajasthan 333031, India
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Extended High-frequency Hearing Impairment Despite a Normal Audiogram: Relation to Early Aging, Speech-in-noise Perception, Cochlear Function, and Routine Earphone Use. Ear Hear 2021; 43:822-835. [PMID: 34700326 DOI: 10.1097/aud.0000000000001140] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Humans can hear up to 20 kHz. Emerging evidence suggests that hearing in the extended high frequencies (EHFs; >8 kHz) contributes to speech perception in noise. The objective of the present study was to describe the features of EHF hearing impairment in young adults with normal standard audiograms (0.25-8 kHz). Specifically, the study goals were to: (1) characterize the EHF hearing impairment and identify potential risk factors; (2) elucidate the age-related changes in EHF hearing; (3) determine the effect of EHF hearing impairment on speech-in-noise recognition; and (4) examine the extent to which EHF hearing impairment influences cochlear functioning in the standard frequencies. DESIGN Hearing thresholds at standard frequencies and EHFs (10, 12.5, 14, and 16 kHz), and speech recognition thresholds (SRTs) using digit triplets in multi-talker babble were measured in both ears from 222 participants (19-38 years; n = 444 ears) with normal audiograms (≤20 dB HL at standard frequencies). Test-retest measurement of hearing thresholds was obtained in a subset of 50 participants (100 ears), and clinical distortion product otoacoustic emissions (f2 frequency = 2, 3, 4, and 5 kHz) were recorded in 49 participants (98 ears). RESULTS Forty-two of 222 participants had EHF hearing impairment (>20 dB HL for at least one EHF in either ear). Only seven individuals with EHF impairment had significant case history and/or listening-in-noise complaints. A breakpoint in the threshold-age function was observed for the EHFs for males but not for females. Linear mixed models revealed a significant effect of age, pure-tone averages for speech frequencies (0.5, 1, 2, and 4 kHz), and EHFs and group (NH versus EHF hearing impairment) independent of each other on the SRTs. Individuals with EHF hearing impairment had less measurable emissions and when present, had a lower magnitude of otoacoustic emissions relative to NH controls. There was no difference in hearing thresholds, SRTs, or otoacoustic emissions between earphone users and nonusers. CONCLUSIONS The hearing thresholds for the EHFs exhibit signs of early auditory aging. Age-related deterioration in auditory function can be observed in the third decade of human life. A breakpoint in the threshold-age function suggests that rapid aging processes are operational at a relatively younger age (21 years) for males. The audibility of EHFs contributes to speech-in-noise recognition. EHF hearing impairment independent of age and speech frequencies can affect speech-in-noise recognition. Reduced distortion product otoacoustic emissions in the standard frequencies may suggest preclinical cochlear degeneration in individuals with EHF hearing impairment.
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50
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Hancock KE, O'Brien B, Santarelli R, Liberman MC, Maison SF. The summating potential in human electrocochleography: Gaussian models and Fourier analysis. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:2492. [PMID: 34717457 PMCID: PMC8637743 DOI: 10.1121/10.0006572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 09/16/2021] [Accepted: 09/17/2021] [Indexed: 05/07/2023]
Abstract
In recent electrocochleographic studies, the amplitude of the summating potential (SP) was an important predictor of performance on word-recognition in difficult listening environments among normal-hearing listeners; paradoxically the SP was largest in those with the worst scores. SP has traditionally been extracted by visual inspection, a technique prone to subjectivity and error. Here, we assess the utility of a fitting algorithm [Kamerer, Neely, and Rasetshwane (2020). J Acoust Soc Am. 147, 25-31] using a summed-Gaussian model to objectify and improve SP identification. Results show that SPs extracted by visual inspection correlate better with word scores than those from the model fits. We also use fast Fourier transform to decompose these evoked responses into their spectral components to gain insight into the cellular generators of SP. We find a component at 310 Hz associated with word-identification tasks that correlates with SP amplitude. This component is absent in patients with genetic mutations affecting synaptic transmission and may reflect a contribution from excitatory post-synaptic potentials in auditory nerve fibers.
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Affiliation(s)
- Kenneth E Hancock
- Department of Otolaryngology - Head & Neck Surgery, Harvard Medical School and Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, Massachusetts 02115, USA
| | - Bennett O'Brien
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, Massachusetts 02115, USA
| | - Rosamaria Santarelli
- Department of Neurosciences, University of Padova, Via Giustiniani 2, 35128 Padova, Italy
| | - M Charles Liberman
- Department of Otolaryngology - Head & Neck Surgery, Harvard Medical School and Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, Massachusetts 02115, USA
| | - Stéphane F Maison
- Department of Otolaryngology - Head & Neck Surgery, Harvard Medical School and Eaton-Peabody Laboratories, Massachusetts Eye & Ear, 243 Charles Street, Boston, Massachusetts 02115, USA
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