Hearing loss among classical-orchestra musicians

Tribute to the Flute: A Literature Review of Playing-Related Problems in Flautists

Playing musical instruments places unusually high demands on specific parts of the human body. Relative to the instruments they play, musicians may experience instrument-related symptoms, as recorded in flute players. The objective was to provide an overview of the study findings addressing medical problems in flautists to better understand their complaints and pave the way for more personalized healthcare. Several electronic databases (PubMed, Embase, Cochrane Library) were systematically searched in July 2022. Furthermore, the references of all included articles were reviewed for additionally relevant sources. The resulting set of studies was summarized in a table, with quality assessment according to the SIGN grading system. From an initial 433 hits, the search yielded 95 studies with a total of 32,600 musicians, including at least 2134 flautists. Among the latter, evidence was found for musculoskeletal, neurological, dermatological, temporomandibular, and hearing complaints, overuse and reflux symptoms, velopharyngeal insufficiency, as well as upper and lower airway impairment. Other specialists may be consulted equally often and should be sensitive to the particular medical problems in flautists. Future studies would ideally contain specific outcome analyses on an international scale and consider flautists as an individual subgroup within a larger number of total participants.

An acoustical environment survey of student music practice

Chronic exposure to loud sound leads to noise-induced hearing loss. This is especially common in collegiate-level musicians. Existing methods for estimating exposure typically do not consider genre- or instrument-specific variability in soundscape/spectral characteristics. We measured sound exposure levels (SELs) across instruments, bands, and genres at a university music school. We found (1) considerable variability in SELs across instruments and bands, (2) that Jazz musicians are consistently exposed to the highest sound levels, and (3) that spectral features of music differ between instrument type and genre, and based on room size. These findings highlight the need for tailored guidelines that moderate the implementation of hearing conservation initiatives for collegiate musicians.

Clinical and investigational tools for monitoring noise-induced hyperacusis

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.

Prevention of Noise-Induced Hearing Loss Using Investigational Medicines for the Inner Ear: Previous Trial Outcomes Should Inform Future Trial Design

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.

Prevalence of Hyperacusis in the General and Special Populations: A Scoping Review

Objectives: To study the prevalence of hyperacusis in the general population and the special population, and to determine the effect of population differences on hyperacusis.

Methods: The two authors followed a scoping review methodology and screened nearly 30 years of English literature in Pubmed, Web of Science, OVID, and EBSCO. Then, the extracted results of each study were discussed in groups and subgroups.

Results: The authors selected 42 pieces of scientific literature that met the requirements, studying a total of 34,796 subjects, including the general population (28,425 subjects), the special occupation population (2,746 subjects), and the patients with concomitant diseases (5,093 subjects). The prevalence was 0.2–17.2% in the general population, 3.8–67% in the special occupation population, and 4.7–95% in the patients with special diseases. It was found that in the general population, the high prevalence occurs in adolescents and older adults. The prevalence of hyperacusis in women is significantly higher than in men. In people with hearing disorders, the prevalence of hyperacusis is significantly higher than in people with normal hearing. Various diseases (such as Williams syndrome, tinnitus, and autism), as well as various occupations (musicians, music students, teachers, and others), have been found to be high risk factors for hyperacusis.

Conclusion: The high prevalence of hyperacusis and the large differences between reported prevalence in different studies deserves our great attention. Additionally, in order to increase the comparability of the studies, a standardized set of criteria are needed to study the prevalence of hyperacusis.

Audiological and noise exposure findings among members of a Brazilian folklore music group

BACKGROUND

Musicians and dancers can be considered an at-risk population for developing noise-induced hearing loss.

OBJECTIVES

To determine the audiological profile of members of a folklore-related music group and quantify noise exposure at their rehearsal venue.

METHODS

This was a quantitative and descriptive study. The musicians and dancers were evaluated in two stages: an interview about their working life, followed by high frequency tonal audiometry. The sound pressure level in the group's rehearsal venue was measured using a BEK 2270 Noise Analyzer.

RESULTS

A total of 7.2% of the subjects had noise-induced hearing loss (NIHL) and 39% of the audiometric tests were notch type. During the interview 31.7% of the subjects mentioned discomfort from loud noise, although none of them used ear protection. The environmental assessment showed inadequate humidity and oscillating temperature. Twenty sound pressure level measurements were performed for Leq (equivalent sound pressure levels) and the results ranged from 88 dB (A) to 99 dB (A) with a mean of 97.05.

CONCLUSIONS

Exposure to high levels of sound pressure has led to NIHL in some members of the group. Some of those with normal hearing also presented a notch configuration characteristic of NIHL. Tinnitus, indicating that a change in hearing has occurred, was the most frequent auditory symptom.

Loud Music and Leisure Noise Is a Common Cause of Chronic Hearing Loss, Tinnitus and Hyperacusis

High sound levels capable of permanently damaging the ear are experienced not only in factories and war zones but in concert halls, nightclubs, sports stadiums, and many other leisure environments. This review summarizes evidence that loud music and other forms of "leisure noise" are common causes of noise-induced hearing loss, tinnitus, and hyperacusis, even if audiometric thresholds initially remain within clinically normal limits. Given the huge global burden of preventable noise-induced hearing loss, noise limits should be adopted in a much broader range of settings, and education to promote hearing conservation should be a higher public health priority.

Pure-Tone Hearing Thresholds and Otoacoustic Emissions in Students of Music Academies

The objective of this study was to assess the hearing of music students in relation to their exposure to excessive sounds. A standard pure-tone audiometry, transient-evoked otoacoustic emissions (TEOAEs) and distortion-product otoacoustic emissions (DPOAEs) were determined in 163 students of music academies, aged 22.8 ± 2.6 years. A questionnaire survey and sound pressure level measurements during solo and group playing were also conducted. The control group comprised 67 subjects, mainly non-music students, aged 22.8 ± 3.3 years. Study subjects were exposed to sounds at the A-weighted weekly noise exposure level (L_EX,w) from 75 to 106 dB. There were no significant differences in the hearing thresholds between groups in the frequency range of 4000-8000 Hz. However, music students compared to control group exhibited lower values of DPOAE amplitude (at 6000 and 7984 Hz) and signal-to-noise ratio (SNR) (at 984, 6000, and 7984 Hz) as well as SNR of TEOAE (in 1000 Hz band). A significant impact of noise exposure level, type of instrument, and gender on some parameters of measured otoacoustic emissions was observed. In particular, music students having L_EX,w ≥ 84.9 dB, compared to those with L_EX,w < 84.9 dB, achieved significantly lower DPOAE amplitude at 3984 Hz. Meanwhile, both TEOAE and DPOAE results indicated worse hearing in students playing percussion instruments vs. wind instruments, and wind instrument players vs. students playing stringed instruments.

Human exposures and their associated hearing loss profiles: Music industry professionals

Music industry professionals represent a vulnerable population to music induced hearing disorders (MIHDs). In addition to the impacts that the development of hearing disorders secondary to noise exposure can have on quality of life and communication, MIHDs can impact the afflicted individual's professional performance, and in turn employability. Within the music industry there are individual and institutional barriers to traditional hearing conservation interventions. Pharmaceutical interventions for hearing loss could potentially address some of these barriers, yet there are significant considerations and cautions which should be addressed.

Tinnitus Severity Is Related to the Sound Exposure of Symphony Orchestra Musicians Independently of Hearing Impairment

Objectives:

Tinnitus can be debilitating and with great impact of musicians professional and private life. The objectives of the study were therefore to: (1) describe the epidemiology of tinnitus including its severity in classical orchestra musicians, (2) investigate the association between tinnitus severity in classical musicians and their cumulative lifetime sound exposure, and (3) the association between tinnitus and hearing thresholds.

Design:

The study population included all musicians from five Danish symphony orchestras. Answers regarding their perception of tinnitus were received from 325 musicians, and 212 musicians were also tested with audiometry. Any tinnitus and severe tinnitus were two definitions of tinnitus used as outcomes and analyzed in relation to an estimation of the cumulative lifetime sound exposure from sound measurements and previously validated questionnaires and the average hearing threshold of 3, 4, and 6 kHz.

Results:

Thirty-five percentage of all musicians (31% female and 38% of male musicians) reported having experienced at least one episode of tinnitus lasting for more than 5 minutes during their life. Severe tinnitus with a severe impact on daily life was reported by 19% of the musicians (18% of female and 21% of male musicians). The severity of tinnitus was associated with increased lifetime sound exposure but not to poorer high frequency hearing thresholds when the lifetime sound exposure was considered. The odds ratio for an increase in one unit of tinnitus severity was 1.25 (95% CI, 1.12–1.40) for every 1 dB increase in lifetime sound exposure.

Conclusion:

Musicians frequently report tinnitus. Any tinnitus and severe tinnitus are significantly associated with the cumulative lifetime sound exposure, which was shown to be the most important factor not only for the prevalence but also for the severity of tinnitus—even in musicians without hearing loss. High-frequency hearing thresholds and tinnitus severity were correlated only if the cumulative lifetime sound exposure was excluded from the analyses.

Hearing Loss, Tinnitus, Hyperacusis, and Diplacusis in Professional Musicians: A Systematic Review

Professional musicians (PMs) are at high risk of developing hearing loss (HL) and other audiological symptoms such as tinnitus, hyperacusis, and diplacusis. The aim of this systematic review is to (A) assess the risk of developing HL and audiological symptoms in PMs and (B) evaluate if different music genres (Pop/Rock Music—PR; Classical Music—CL) expose PMs to different levels of risk of developing such conditions. Forty-one articles including 4618 PMs were included in the study. HL was found in 38.6% PMs; prevalence was significantly higher among PR (63.5%) than CL (32.8%) PMs; HL mainly affected the high frequencies in the 3000-6000 Hz range and was symmetric in 68% PR PMs and in 44.5% CL PMs. Tinnitus was the most common audiological symptom, followed by hyperacusis and diplacusis. Tinnitus was almost equally distributed between PR and CL PMs; diplacusis was more common in CL than in PR PMs, while prevalence of hyperacusis was higher among PR PMs. Our review showed that PR musicians have a higher risk of developing HL compared to CL PMs; exposure to sounds of high frequency and intensity and absence of ear protection may justify these results. Difference in HL symmetry could be explained by the type of instruments used and consequent single-sided exposure.

Noise exposure and auditory thresholds of military musicians: a follow up study

Background

Military musicians are working in a noisy environment with high sound exposure levels above the international standards. Aim of the current study is to find out, whether they develop the expected hearing impairments. Adherence to the regulations for prevention in musicians is more difficult than in other occupational fields.

Methods

In an interval of 13.3 years, 36 out of 58 male military musicians of a German army music corps were subjected twice to an audiometric audit. There were no exclusion criteria apart from acute ENT infections (three musicians). These results were compared with one another and evaluated by means of statistical methods for relationships with several factors.

Results

At frequencies below 3 kHz, the follow-up audiograms were up to 5 dB better than the preliminary examination. From 4 kHz up to 8 kHz the preliminary investigations showed less hearing impairment. Averaging all frequencies the improvement of hearing ability was around 1 dB. Above 1 kHz the average hearing of the right ear was up to 7 dB better than that of the left ear. Age-induced hearing loss was 3 to 8 dB lower than predicted by ISO standards over the entire frequency range. The side of the ear (right/left) and the frequency (3, 4, and 6 kHz) were significant (p < 0.05) in hearing loss, whereas the influence of the instrument and the acoustic traumata were not.

Conclusion

Despite the high noise levels, the average hearing ability of the 36 military musicians during the investigation period only slightly deteriorated in the noise-sensitive frequencies (3, 5 and 6 kHz). Music may be less harmful than industrial noise, or the long-term auditory training of the musicians leads to a delayed presbycusis.

Musicianship enhances ipsilateral and contralateral efferent gain control to the cochlea

Human hearing sensitivity is easily compromised with overexposure to excessively loud sounds, leading to permanent hearing damage. Consequently, finding activities and/or experiential factors that distinguish "tender" from "tough" ears (i.e., acoustic vulnerability) would be important for identifying people at higher risk for hearing damage. To regulate sound transmission and protect the inner ear against acoustic trauma, the auditory system modulates gain control to the cochlea via biological feedback of the medial olivocochlear (MOC) efferents, a neuronal pathway linking the lower brainstem and cochlear outer hair cells. We hypothesized that a salient form of auditory experience shown to have pervasive neuroplastic benefits, namely musical training, might act to fortify hearing through tonic engagement of these reflexive pathways. By measuring MOC efferent feedback via otoacoustic emissions (cochlear emitted sounds), we show that dynamic ipsilateral and contralateral cochlear gain control is enhanced in musically-trained individuals. Across all participants, MOC strength was correlated with the years of listeners' training suggested that efferent gain control is experience dependent. Our data provide new evidence that intensive listening experience(s) (e.g., musicianship) can strengthen the ipsi/contralateral MOC efferent system and sound regulation to the inner ear. Implications for reducing acoustic vulnerability to damaging sounds are discussed.

A Role of Medial Olivocochlear Reflex as a Protection Mechanism from Noise-Induced Hearing Loss Revealed in Short-Practicing Violinists

Previous studies have indicated that extended exposure to a high level of sound might increase the risk of hearing loss among professional symphony orchestra musicians. One of the major problems associated with musicians' hearing loss is difficulty in estimating its risk simply on the basis of the physical amount of exposure, i.e. the exposure level and duration. The aim of this study was to examine whether the measurement of the medial olivocochlear reflex (MOCR), which is assumed to protect the cochlear from acoustic damage, could enable us to assess the risk of hearing loss among musicians. To test this, we compared the MOCR strength and the hearing deterioration caused by one-hour instrument practice. The participants in the study were music university students who are majoring in the violin, whose left ear is exposed to intense violin sounds (broadband sounds containing a significant number of high-frequency components) during their regular instrument practice. Audiogram and click-evoked otoacoustic emissions (CEOAEs) were measured before and after a one-hour violin practice. There was a larger exposure to the left ear than to the right ear, and we observed a left-ear specific temporary threshold shift (TTS) after the violin practice. Left-ear CEOAEs decreased proportionally to the TTS. The exposure level, however, could not entirely explain the inter-individual variation in the TTS and the decrease in CEOAE. On the other hand, the MOCR strength could predict the size of the TTS and CEOAE decrease. Our findings imply that, among other factors, the MOCR is a promising measure for assessing the risk of hearing loss among musicians.

Occupational noise exposure and hearing: a systematic review

Purpose

To give a systematic review of the development of noise-induced hearing loss (NIHL) in working life.

Methods

A literature search in MEDLINE, Embase, Web of Science, Scopus, and Health and Safety Abstracts, with appropriate keywords on noise in the workplace and health, revealed 22,413 articles which were screened by six researchers. A total of 698 articles were reviewed in full text and scored with a checklist, and 187 articles were found to be relevant and of sufficient quality for further analysis.

Results

Occupational noise exposure causes between 7 and 21 % of the hearing loss among workers, lowest in the industrialized countries, where the incidence is going down, and highest in the developing countries. It is difficult to distinguish between NIHL and age-related hearing loss at an individual level. Most of the hearing loss is age related. Men lose hearing more than women do. Heredity also plays a part. Socioeconomic position, ethnicity and other factors, such as smoking, high blood pressure, diabetes, vibration and chemical substances, may also affect hearing. The use of firearms may be harmful to hearing, whereas most other sources of leisure-time noise seem to be less important. Impulse noise seems to be more deleterious to hearing than continuous noise. Occupational groups at high risk of NIHL are the military, construction workers, agriculture and others with high noise exposure.

Conclusion

The prevalence of NIHL is declining in most industrialized countries, probably due to preventive measures. Hearing loss is mainly related to increasing age.

Electronic supplementary material

The online version of this article (doi:10.1007/s00420-015-1083-5) contains supplementary material, which is available to authorized users.

A review of hyperacusis and future directions: part I. Definitions and manifestations

PURPOSE

Hyperacusis can be extremely debilitating, and at present, there is no cure. We provide an overview of the field, and possible related areas, in the hope of facilitating future research.

METHOD

We review and reference literature on hyperacusis and related areas. We have divided the review into 2 articles. In Part I, we discuss definitions, epidemiology, different etiologies and subgroups, and how hyperacusis affects people. In Part II, we review measurements, models, mechanisms, and treatments, and we finish with some suggestions for further research.

RESULTS

Hyperacusis encompasses a wide range of reactions to sound, which can be grouped into the categories of excessive loudness, annoyance, fear, and pain. Many different causes have been proposed, and it will be important to appreciate and quantify different subgroups. Reasonable approaches to assessing the different forms of hyperacusis are emerging, including psychoacoustical measures, questionnaires, and brain imaging.

CONCLUSIONS

Hyperacusis can make life difficult for many, forcing sufferers to dramatically alter their work and social habits. We believe this is an opportune time to explore approaches to better understand and treat hyperacusis.

The Alexander Technique and musicians: a systematic review of controlled trials

BACKGROUND

Musculoskeletal disorders, stress and performance anxiety are common in musicians. Therefore, some use the Alexander Technique (AT), a psycho-physical method that helps to release unnecessary muscle tension and re-educates non-beneficial movement patterns through intentional inhibition of unwanted habitual behaviours. According to a recent review AT sessions may be effective for chronic back pain. This review aimed to evaluate the evidence for the effectiveness of AT sessions on musicians' performance, anxiety, respiratory function and posture.

METHODS

The following electronic databases were searched up to February 2014 for relevant publications: PUBMED, Google Scholar, CINAHL, EMBASE, AMED, PsycINFO and RILM. The search criteria were "Alexander Technique" AND "music*". References were searched, and experts and societies of AT or musicians' medicine contacted for further publications.

RESULTS

237 citations were assessed. 12 studies were included for further analysis, 5 of which were randomised controlled trials (RCTs), 5 controlled but not randomised (CTs), and 2 mixed methods studies. Main outcome measures in RCTs and CTs were music performance, respiratory function, performance anxiety, body use and posture. Music performance was judged by external experts and found to be improved by AT in 1 of 3 RCTs; in 1 RCT comparing neurofeedback (NF) to AT, only NF caused improvements. Respiratory function was investigated in 2 RCTs, but not improved by AT training. Performance anxiety was mostly assessed by questionnaires and decreased by AT in 2 of 2 RCTs and in 2 of 2 CTs.

CONCLUSIONS

A variety of outcome measures has been used to investigate the effectiveness of AT sessions in musicians. Evidence from RCTs and CTs suggests that AT sessions may improve performance anxiety in musicians. Effects on music performance, respiratory function and posture yet remain inconclusive. Future trials with well-established study designs are warranted to further and more reliably explore the potential of AT in the interest of musicians.

Sound Practice-improving occupational health and safety for professional orchestral musicians in Australia

The Sound Practice Project is a 5-year study involving baseline evaluation, development, and implementation of musician-specific work health and safety initiatives. A cross-sectional population physical and psychological survey and physical assessment were conducted at the same time, with an auditory health assessment conducted later. The results were used to guide the development of a series of targeted interventions, encompassing physical, psychological, and auditory health components. This paper provides an overview of the project but focuses on the health findings arising from the cross-sectional survey. Three hundred and seventy-seven musicians from the eight professional symphony orchestras in Australia took part in the cross-sectional study (about 70% of eligible musicians). Eighty-four percent (84%) of musicians reported past performance-related musculoskeletal disorder (PRMD) episodes; 50% were suffering a current PRMD. Of the 63% who returned hearing surveys, 43% believed they had hearing loss, and 64% used earplugs at least intermittently. Noise exposure was found to be high in private practice, although awareness of risk and earplug use in this environment was lower than in orchestral settings. Improved strategic approaches, acoustic screens and recently developed active earplugs were found to provide effective new options for hearing protection. With respect to psychosocial screening, female musicians reported significantly more trait anxiety, music performance anxiety, social anxiety, and other forms of anxiety and depression than male musicians. The youngest musicians were significantly more anxious compared with the oldest musicians. Thirty-three percent (33%) of musicians may meet criteria for a diagnosis of social phobia; 32% returned a positive depression screen and 22% for post-traumatic stress disorder (PTSD). PRMDs and trigger point discomfort levels were strongly associated with increasing severity of psychological issues such as depression and music performance anxiety.

Hearing loss prevention education using adopt-a-band: changes in self-reported earplug use in two high school marching bands

PURPOSE

Hearing loss prevention has always been an important issue for audiologists. The importance of hearing loss prevention education for young musicians is now recognized by the National Association for Music Education as well as the National Association of Schools of Music. Adopt-a-Band is a commercial program designed to foster hearing loss prevention behavior in young musicians.

METHOD

This study assessed changes in earplug use, measured using self-report surveys, after Adopt-a-Band training. Participants were members of 2 high school marching bands who viewed an informational DVD and reviewed fact sheets. Flat-attenuation earplugs were distributed, and training was provided. In addition, study participants engaged in discussion of hearing loss with a doctor of audiology student.

RESULTS

Before training, 23% of participants reported they had previously used hearing protection. Immediately after training, 94% of participants reported they planned to use hearing protection at least occasionally. In a final end-of-season survey, earplug use had reliably increased; 62% of participants reported they used earplugs at least occasionally.

CONCLUSIONS

Earplug use increased, but self-reported behavioral change was not as robust as predicted from self-reported participant intentions. Participant comments regarding factors that influenced their earplug use decisions suggest opportunities to improve training.

A clinical trial of active hearing protection for orchestral musicians

Orchestral musicians-an at-risk group for noise-induced hearing loss-have consistently reported great difficulty using hearing protection while performing or rehearsing, even when using earplugs specifically designed for musicians. A recent innovation in this field has been electronic earplugs that claim to deliver very high quality sound and only attenuate when sound levels become excessive. This study investigated these claims, aiming to determine whether professional orchestral musicians were able to use these devices and whether they were preferred to existing earplugs. Initially clinical and laboratory testing was carried out on the devices, indicating some spectral alteration of processed sound occurred, however claims of attenuation properties were validated. Following this, 26 orchestral musicians used the devices during rehearsals and performances for at least four weeks, providing feedback throughout this period. While musicians preferred the devices to previous earplugs, they identified issues including difficulty with orchestral balance, perception of dynamics and quality of sound provided by the devices. Results indicate these earplugs are a very positive step towards a usable hearing conservation tool for orchestral musicians to use in conjunction with other risk mitigation measures.

Function and plasticity of the medial olivocochlear system in musicians: a review

The outer hair cells of the organ of Corti are the target of abundant efferent projections from the olivocochlear system. This peripheral efferent auditory subsystem is currently thought to be modulated by central activity via corticofugal descending auditory system, and to modulate active cochlear micromechanics. Although the function of this efferent subsystem remains unclear, physiological, psychophysical, and modeling data suggest that it may be involved in ear protection against noise damage and auditory perception, especially in the presence of background noise. Moreover, there is mounting evidence that its activity is modulated by auditory and visual attention. A commonly used approach to measure olivocochlear activity noninvasively in humans relies on the suppression of otoacoustic emissions by contralateral noise. Previous studies have found substantial interindividual variability in this effect, and statistical differences have been observed between professional musicians and non-musicians, with stronger bilateral suppression effects in the former. In this paper, we review these studies and discuss various possible interpretations for these findings, including experience-dependent neuroplasticity. We ask whether differences in olivocochlear function between musicians and non-musicians reflect differences in peripheral auditory function or in more central factors, such as top-down attentional modulation.

Facing the music: pre- and postconcert assessment of hearing in teenagers

OBJECTIVE

Determine the effect of exposure to a single rock/pop concert on pure-tone hearing thresholds and outer hair cell function in teenagers.

STUDY DESIGN

Repeated measures pre- and postconcert assessment of hearing.

SETTING

Mobile hearing conservation test vehicle and large indoor concert venue.

SUBJECTS

Twenty-nine normal-hearing teenagers and young adults ages 13 to 20 years.

INTERVENTION

Attendance at a public rock/pop concert.

MAIN OUTCOME MEASURES

Pre- and postconcert pure-tone thresholds in both ears from 500 Hz to 8 kHz, pure-tone average (PTA) for 2, 3, and 4 kHz, distortion product otoacoustic emissions (DPOAEs), proportion of subjects experiencing a PTA change of 10 dB or greater.

RESULTS

Concert sound levels at the subjects' position averaged 98.5 dBA. Only 3 subjects used the hearing protection provided. Thresholds for 2 to 6 kHz increased significantly from pre- to postconcert (p ≤ 0.001). The increase in PTA (2, 3, and 4 kHz) between test intervals averaged 6.3 and 6.5 dB for the right and left ears, respectively, and 33.3% of subjects had a threshold shift of 10 dB or greater in the PTA in at least 1 ear (p ≤ 0.001). The number of subjects experiencing a reduction in DPOAE amplitude (17/25) and the change in mean amplitude were statistically significant (p ≤ 0.001 and p ≤ 0.004, respectively).

CONCLUSION

Exposure to a single live-music rock/pop concert can produce a threshold shift and decrease in otoacoustic emissions amplitude indicating impact on outer hair cell function. Results clearly indicate a need for research on this public health issue regarding "safe" listening levels, especially in younger people with more years for accrual of damage.

Relative risk of elevated hearing threshold compared to ISO1999 normative populations for Royal Australian Air Force male personnel

OBJECTIVE

This paper introduces a new method to calculate relative risks of elevated hearing thresholds, at various ages and frequencies, between a study population and ISO1999:2003: Annex A Screened, Annex B Unscreened and ISO1999 Section 5.3 adjustment for noise exposure using Annex A Screened data. We demonstrate this method on a study population of male Royal Australian Air Force personnel.

STUDY DESIGN

Using a retrospective cohort design, hearing thresholds were assessed in 583 F-111 aircraft maintenance personnel, 377 technical-trade comparisons and 492 non-technical comparisons using pure-tone audiometry. A quantile regression model was used determine whether an association exists between median hearing thresholds and F-111 maintenance, adjusting for possible confounders. The new method involves using quantile regression models with bootstrapped standard errors to estimate percentiles for the study population and thus determine the probability of a greater than 25 dB hearing threshold. This was done for the three ISO datasets as follows; for the ISO1999 Annex A screened population data the formula provided allows the calculation of these probabilities. ISO1999 Annex B unscreened population data only provides the values for the 10th, 50th and 90th percentiles at ages 30, 40, 50 and 60 only, therefore it was necessary to fit a curve to these values in order to estimate the probabilities. For ISO1999 Section 5.3 adjustment for noise exposure population we used the Annex A screened population data plus the formula. The probabilities were then divided to give the relative risks of a greater than 25 dB hearing threshold, at various ages and frequencies.

RESULTS

While no difference was observed between the three groups, the model identified a number of significant confounders, namely tinnitus, smoking, diabetes and the use of anti-depressant medications. Relative risks were high at frequencies 2 kHz and less for the study population of all ages compared to ISO A screened data. The increased relative risks at 4 and 6 kHz give the appearance of a "noise notch" for ages 30 and 40 years. The comparison with the ISO B unscreened data are significantly less than one for frequencies above 2 kHz, particularly for young men and greater than one less than 2 kHz. The relative risks for the comparison to the ISO A screened data with ISO 5.3 adjustments, are highest for young men decreasing with age, with the highest relative risk are at frequencies less than 2 kHz.

CONCLUSIONS

This paper demonstrates a new method for quantifying the probability of a clinically relevant hearing loss and the relative risk of the loss due to a risk factor. Prior to this, researchers were reduced to simplistic methods such as visual comparison of deciles which did not enable the estimation of risk. The new method can use all observed hearing thresholds per study participant, adjust for known confounding factors such age and gender, and calculate the relative risk of a clinically relevant increase in hearing threshold due to a risk factor of interest.

Hearing conservation and noise management practices in professional orchestras

Hearing conservation and noise exposure management for professional orchestras is a difficult issue resistant to standard control measures as used in other industries with excessive noise problems. Although there has been a great deal of research into this area in terms of the audiological status of musicians and their exposure to noise, there are relatively few industry-specific strategies that can be adopted by an orchestra looking to address these issues. Australia does not have a uniform approach to hearing conservation management in its orchestras; however, each orchestra actively grapples with the challenges of balancing legal, practical, and artistic concerns. This study systematically investigated hearing conservation practices, noise exposure management, and audiological screening protocols in eight professional orchestras. The research involved personal interviews with staff at each orchestra, including inspection of venues and facilities. While all these orchestras were aware of the risks and were actively taking significant steps to reduce noise exposure, a range of approaches, with varying degrees of effectiveness and understanding of the issue, were found across the sector. There was limited evidence of educational programs for either the musicians at risk of excessive noise exposure or the staff responsible for devising and implementing control measures. In addition, the reported use of adequate personal hearing protection by musicians was poor. As Australia has recently introduced a national approach to workplace health and safety, a similar approach to noise and audiological management across the country's orchestral sector is proposed, drawn from existing research and practice. This will enable both consistent procedures and meaningful dialogue between the orchestras on the topics of hearing conservation, audiological monitoring, and educational practices.

Sound exposure of symphony orchestra musicians

BACKGROUND

Assessment of sound exposure by noise dosimetry can be challenging especially when measuring the exposure of classical orchestra musicians where sound originate from many different instruments. A new measurement method of bilateral sound exposure of classical musicians was developed and used to characterize sound exposure of the left and right ear simultaneously in two different symphony orchestras.

OBJECTIVES

To measure binaural sound exposure of professional classical musicians and to identify possible exposure risk factors of specific musicians.

METHODS

Sound exposure was measured with microphones mounted on the musician's ears and recorded digitally. The recorded sound was analysed and the specific sound exposure of the left and the right ear was determined for the musicians. A total of 114 measurements covering 106 h were recorded in two symphony orchestras.

RESULTS

Sound exposure depends significantly on the specific instrument and the repertoire played by the exposed musician. Concerts, group rehearsals and individual practice were all significant contributors to the sound exposure. The highest L(Aeq) of 86 -98 dB was found among the brass players. High string players were exposed from 82 to 98 dBA and their left ear was exposed 4.6 dB more than the right ear. Percussionists were exposed to high sound peaks >115 dBC but less continuous sound exposure was observed in this group. Musicians were exposed up to L(Aeq8h) of 92 dB and a majority of musicians were exposed to sound levels exceeding L(Aeq8h) of 85 dB.

CONCLUSIONS

Binaural recording of the individual sound exposure showed that orchestra musicians could be exposed differently to the left and right ear and that they were primarily exposed from their own instruments. Specific repertoires as well as the specific instrument determine the level of exposure.