A review of the perceptual effects of hearing loss for frequencies above 3 kHz.

BACKGROUND: Hearing loss caused by exposure to intense sounds usually has its greatest effects on audiometric thresholds at 4 and 6 kHz. However, in several countries compensation for occupational noise-induced hearing loss is calculated using the average of audiometric thresholds for selected frequencies up to 3 kHz, based on the implicit assumption that hearing loss for frequencies above 3 kHz has no material adverse consequences. This paper assesses whether this assumption is correct. DESIGN: Studies are reviewed that evaluate the role of hearing for frequencies above 3 kHz. RESULTS: Several studies show that frequencies above 3 kHz are important for the perception of speech, especially when background sounds are present. Hearing at high frequencies is also important for sound localization, especially for resolving front-back confusions. CONCLUSIONS: Hearing for frequencies above 3 kHz is important for the ability to understand speech in background sounds and for the ability to localize sounds. The audiometric threshold at 4 kHz and perhaps 6 kHz should be taken into account when assessing hearing in a medico-legal context.The work of the author is supported by the Engineering and Physical Sciences Research Council (UK, grant number RG78536).This is the final version of the article. It first appeared from Taylor & Francis via https://doi.org/10.1080/14992027.2016.120456

The Effect of Exposure to Noise during Military Service on the Subsequent Progression of Hearing Loss.

This paper reviews and re-analyses data from published studies on the effects of noise exposure on the progression of hearing loss once noise exposure has ceased, focusing particularly on noise exposure during military service. The data are consistent with the idea that such exposure accelerates the progression of hearing loss at frequencies where the hearing loss is absent or mild at the end of military service (hearing threshold levels (HTLs) up to approximately 50 dB HL), but has no effect on or slows the progression of hearing loss at frequencies where the hearing loss exceeds approximately 50 dB. Acceleration appears to occur over a wide frequency range, including 1 kHz. However, each of the studies reviewed has limitations. There is a need for further longitudinal studies of changes in HTLs over a wide range of frequencies and including individuals with a range of HTLs and ages at the end of military service. Longitudinal studies are also needed to establish whether the progression of hearing loss following the end of exposure to high-level sounds depends on the type of noise exposure (steady broadband factory noises versus impulsive sounds)

Is there a role for a Carer Support Nurse?

Carers play a vital role in supporting family and friends with health conditions, particularly long-term health conditions. This impacts on their own health and well-being. The NHS is committed to supporting carers, and community nurses are well-placed to identify and support them, but changes in the workforce and the patient population mean that nurses’ time is limited: their focus is on meeting patients’ needs. We propose a solution: a Carer Support Nurse role, dedicated to the needs of carers. We would welcome your views on this proposal

Factors Associated With Depression in Patients With Tinnitus and Hyperacusis.

PURPOSE: The purpose of this study was to assess factors associated with depression for patients with tinnitus and hyperacusis. METHOD: Data were gathered from the records of 620 consecutive patients who sought help concerning their tinnitus or hyperacusis from an audiology clinic in the United Kingdom. RESULTS: One third of the patients had borderline abnormal or abnormal scores on the Depression subscale of the Hospital Anxiety and Depression Scale (HADS-D). Linear regression models showed that HADS-D scores were related to scores for tinnitus handicap, tinnitus loudness, and uncomfortable loudness levels. Mediation analyses showed that (a) the influence of tinnitus handicap scores on HADS-D scores was mainly mediated via the effects of insomnia, hyperacusis, and anxiety; (b) the influence of tinnitus loudness scores on HADS-D scores was fully mediated via the effects of tinnitus handicap, insomnia, hyperacusis handicap, and anxiety; (c) and the small influence of uncomfortable loudness levels on HADS-D scores was fully mediated by hyperacusis handicap and anxiety. CONCLUSION: Those involved in the management of patients with tinnitus and/or hyperacusis should use a wide range of instruments to assess the full impact of tinnitus on a patient's life and should be prepared to refer a patient for treatment for depression, especially when the patient has anxiety, hyperacusis, and/or insomnia

Diagnosing Noise-Induced Hearing Loss Sustained During Military Service Using Deep Neural Networks

The diagnosis of noise-induced hearing loss (NIHL) is based on three requirements: a history of exposure to noise with the potential to cause hearing loss; the absence of known causes of hearing loss other than noise exposure; and the presence of certain features in the audiogram. All current methods for diagnosing NIHL have involved examination of the typical features of the audiograms of noise-exposed individuals and the formulation of quantitative rules for the identification of those features. This article describes an alternative approach based on the use of multilayer perceptrons (MLPs). The approach was applied to databases containing the ages and audiograms of individuals claiming compensation for NIHL sustained during military service (M-NIHL), who were assumed mostly to have M-NIHL, and control databases with no known exposure to intense sounds. The MLPs were trained so as to classify individuals as belonging to the exposed or control group based on their audiograms and ages, thereby automatically identifying the features of the audiogram that provide optimal classification. Two databases (noise exposed and nonexposed) were used for training and validation of the MLPs and two independent databases were used for evaluation and further analyses. The best-performing MLP was one trained to identify whether or not an individual had M-NIHL based on age and the audiogram for both ears. This achieved a sensitivity of 0.986 and a specificity of 0.902, giving an overall accuracy markedly higher than for previous methods

Prevalence and Characteristics of Patients with Severe Hyperacusis among Patients Seen in a Tinnitus and Hyperacusis Clinic.

PURPOSE: The purpose was to assess the proportion of patients seeking help for tinnitus and/or hyperacusis who have severe hyperacusis and to examine factors associated with severe hyperacusis. RESEARCH DESIGN: This was a retrospective cross-sectional study based on 362 consecutive patients who attended a National Health Service audiology clinic for tinnitus and/or hyperacusis rehabilitation and for whom uncomfortable loudness levels (ULLs) had been measured. The criterion for severe hyperacusis was taken as a ULL of 30 dB HL or less for at least one of the measured frequencies for at least one ear. RESULTS: Thirteen patients had severe hyperacusis, and eight of those had normal hearing. The lowest average ULL across frequencies was 28 dB HL. The difference in average ULLs between ears was 5 dB or less for nine patients. The range of ULLs across frequencies was between 5 and 60 dB, ULLs often being lowest at 8 kHz. Eleven patients had tinnitus, eight had otological abnormalities, twelve had mental health problems, and six were taking antidepressants. CONCLUSIONS: Severe hyperacusis is characterized by low ULLs for specific frequencies and no or mild hearing loss. Given the high incidence of tinnitus, otological abnormalities, and mental health problems, the management of patients with severe hyperacusis should involve otologists and psychiatrists in addition to audiologists

Amplitude-modulation detection by recreational-noise-exposed humans with near-normal hearing thresholds and its medium-term progression.

Noise exposure can affect the functioning of cochlear inner and outer hair cells (IHC/OHC), leading to multiple perceptual changes. This work explored possible changes in detection of amplitude modulation (AM) at three Sensation Levels (SL) for carrier frequencies of 3, 4 and 6 kHz. There were two groups of participants, aged 19 to 24 (Young) and 26 to 35 (Older) years. All had near-normal audiometric thresholds. Participants self-assessed exposure to high-level noise in recreational settings. Each group was sub-grouped into low-noise (LN) or high-noise (HN) exposure. AM detection thresholds were worse for the HN than for the LN sub-group at the lowest SL, for the males only of the Young group and for both genders for the Older group, despite no significant difference in absolute threshold at 3 and 4 kHz between sub-groups. AM detection at the lowest SL, at both 3 and 4 kHz, generally improved with increasing age and increasing absolute threshold, consistent with a recruitment-like process. However, poorer AM detection was correlated with increasing exposure at 3 kHz in the Older group. It is suggested that high-level noise exposure produces both IHC- and OHC-related damage, the balance between the two varying across frequency. However, the use of AM detection offers poor sensitivity as a measure of the effects.This is the final version. It was first published by Elsevier at http://www.sciencedirect.com/science/article/pii/S0378595514001506

The effect of musicianship, contralateral noise, and ear of presentation on the detection of changes in temporal fine structure.

Musicians are better than non-musicians at discriminating changes in the fundamental frequency (F0) of harmonic complex tones. Such discrimination may be based on place cues derived from low resolved harmonics, envelope cues derived from high harmonics, and temporal fine structure (TFS) cues derived from both low and high harmonics. The present study compared the ability of highly trained violinists and non-musicians to discriminate changes in complex sounds that differed primarily in their TFS. The task was to discriminate harmonic (H) and frequency-shifted inharmonic (I) tones that were bandpass filtered such that the components were largely or completely unresolved. The effect of contralateral noise and ear of presentation was also investigated. It was hypothesized that contralateral noise would activate the efferent system, helping to preserve the neural representation of envelope fluctuations in the H and I stimuli, thereby improving their discrimination. Violinists were significantly better than non-musicians at discriminating the H and I tones. However, contralateral noise and ear of presentation had no effect. It is concluded that, compared to non-musicians, violinists have a superior ability to discriminate complex sounds based on their TFS, and this ability is unaffected by contralateral stimulation or ear of presentation

Evaluation of a multi-channel algorithm for reducing transient sounds.

OBJECTIVE: The objective was to evaluate and select appropriate parameters for a multi-channel transient reduction (MCTR) algorithm for detecting and attenuating transient sounds in speech. DESIGN: In each trial, the same sentence was played twice. A transient sound was presented in both sentences, but its level varied across the two depending on whether or not it had been processed by the MCTR and on the "strength" of the processing. The participant indicated their preference for which one was better and by how much in terms of the balance between the annoyance produced by the transient and the audibility of the transient (they were told that the transient should still be audible). STUDY SAMPLE: Twenty English-speaking participants were tested, 10 with normal hearing and 10 with mild-to-moderate hearing-impairment. Frequency-dependent linear amplification was provided for the latter. RESULTS: The results for both participant groups indicated that sounds processed using the MCTR were preferred over the unprocessed sounds. For the hearing-impaired participants, the medium and strong settings of the MCTR were preferred over the weak setting. CONCLUSIONS: The medium and strong settings of the MCTR reduced the annoyance produced by the transients while maintaining their audibility.EPSRC RG7853

No Influence of Musicianship on the Effect of Contralateral Stimulation on Frequency Selectivity.

The efferent system may control the gain of the cochlea and thereby influence frequency selectivity. This effect can be assessed using contralateral stimulation (CS) applied to the ear opposite to that used to assess frequency selectivity. The effect of CS may be stronger for musicians than for nonmusicians. To assess whether this was the case, psychophysical tuning curves (PTCs) were compared for 12 musicians and 12 nonmusicians. The PTCs were measured with and without a 60-dB sound pressure level (SPL) pink-noise CS, using signal frequencies of 2 and 4 kHz. The sharpness of the PTCs was quantified using the measure Q10, the signal frequency divided by the PTC bandwidth measured 10 dB above the level at the tip. Q10 values were lower in the presence of the CS, but this effect did not differ significantly for musicians and nonmusicians. The main effect of group (musicians vs. nonmusicians) on the Q10 values was not significant. Overall, these results do not support the idea that musicianship enhances contralateral efferent gain control as measured using the effect of CS on PTCs