In the present study, pure-tone audiometry was used in 687 Finnish school children, aged 6-15 years, to determine the prevalence of a 6 kHz acoustic dip and related factors among three age groups. Trained audiometricians tested air conduction thresholds in a sound-proof room. A total of 57 children (8.3%) had a clear-cut dip of at least 20 dB at 6 kHz. This dip was more pronounced in older children and in boys. A thorough case history was obtained by questionnaire, with logistic regression analysis showing that low birth weight (
The acceptable noise level (ANL) test is used for quantification of the amount of background noise subjects accept when listening to speech. This study investigates Danish hearing-aid users' ANL performance using Danish and non-semantic speech signals, the repeatability of ANL, and the association between ANL and outcome of the international outcome inventory for hearing aids (IOI-HA).
ANL was measured in three conditions in both ears at two test sessions. Subjects completed the IOI-HA and the ANL questionnaire.
Sixty-three Danish hearing-aid users; fifty-seven subjects were full time users and 6 were part time/non users of hearing aids according to the ANL questionnaire.
ANLs were similar to results with American English speech material. The coefficient of repeatability (CR) was 6.5-8.8 dB. IOI-HA scores were not associated to ANL.
Danish and non-semantic ANL versions yield results similar to the American English version. The magnitude of the CR indicates that ANL with Danish and non-semantic speech materials is not suitable for prediction of individual patterns of future hearing-aid use or evaluation of individual benefit from hearing-aid features. The ANL with Danish and non-semantic speech materials is not related to IOI-HA outcome.
The acceptable noise level (ANL) test is a method for quantifying the amount of background noise that subjects accept when listening to speech. Large variations in ANL have been seen between normal-hearing subjects and between studies of normal-hearing subjects, but few explanatory variables have been identified.
To explore a possible relationship between a Swedish version of the ANL test, working memory capacity (WMC), and auditory evoked potentials (AEPs).
ANL, WMC, and AEP were tested in a counterbalanced order across subjects.
Twenty-one normal-hearing subjects participated in the study (14 females and 7 males; aged 20-39 yr with an average of 25.7 yr).
Reported data consists of age, pure-tone average (PTA), most comfortable level (MCL), background noise level (BNL), ANL (i.e., MCL - BNL), AEP latencies, AEP amplitudes, and WMC. Spearman's rank correlation coefficient was calculated between the collected variables to investigate associations. A principal component analysis (PCA) with Varimax rotation was conducted on the collected variables to explore underlying factors and estimate interactions between the tested variables. Subjects were also pooled into two groups depending on their results on the WMC test, one group with a score lower than the average and one with a score higher than the average. Comparisons between these two groups were made using the Mann-Whitney U-test with Bonferroni correction for multiple comparisons.
A negative association was found between ANL and WMC but not between AEP and ANL or WMC. Furthermore, ANL is derived from MCL and BNL, and a significant positive association was found between BNL and WMC. However, no significant associations were seen between AEP latencies and amplitudes and the demographic variables, MCL, and BNL. The PCA identified two underlying factors: One that contained MCL, BNL, ANL, and WMC and another that contained latency for wave Na and amplitudes for waves V and Na-Pa. Using the variables in the first factor, the findings were further explored by pooling the subjects into two groups according to their WMC (WMClow and WMChigh). It was found that the WMClow had significantly poorer BNL than the WMChigh.
The findings suggest that there is a strong relationship between BNL and WMC, while the association between MCL, ANL, and WMC seems less clear-cut.
PURPOSE: Patients with insulin-dependent diabetes mellitus (IDDM) are especially susceptible to microangiopathic complications such as nephropathy, retinopathy, and neuropathy. Microangiopathic changes are also the most important findings in histopathologic studies of the inner ear and central nervous systems in diabetic subjects. No previous studies have measured acoustic-reflex latencies (ARL) or amplitudes (ARA) in patients with IDDM. ARL and ARA reflect the function of the acoustic-reflex arch. Furthermore, possible changes in the tympanic membrane, ossicular chain, and stapedius muscle may affect the shape of acoustic-reflex. SUBJECTS AND METHODS: Acoustic-reflex thresholds, latencies, and amplitudes were studied in 53 patients with IDDM and 42 randomly selected nondiabetic control subjects, aged between 20 and 40 years, using the Madsen Model ZO 73 Impedance Bridge (Madsen Electronics, Copenhagen, Denmark). Subjects with an abnormal tympanic membrane, conductive hearing loss, and known cause for hearing impairment eg, noise damage, were excluded from the study. RESULTS: There were no differences between control and diabetic subjects in the contralateral acoustic-reflex thresholds. In contrast, patients with IDDM had longer ARLs and decreased ARAs compared with those of control subjects. ARA amplitude had linear correlation with the amplitude of tympanogram, whereas ARL had no linear correlation with auditory brainstem latencies in the same study subjects. Acoustic-reflex responses in insulin-dependent diabetic patients were not associated with the duration of diabetes, metabolic control, microangiopathy, or neuropathy. CONCLUSIONS: Prolonged ARLs and decreased ARAs in patients with insulin-dependent diabetes are probably caused more by the stiff middle ear system than disturbances in the brainstem.
The study compares the audiological profile of a group of first-time applicants for hearing aids, a group of re-applicants and a group of non-complainers, aged 70-75 years (n = 71). In spite of overlap in range, a significant difference in thresholds and discrimination was found. The lip-reading capacity was well preserved in the elderly, but showed a significant correlation to the general health condition. The audiological benefit of hearing-aids did not increase with early fitting. General satisfaction with life was independent of satisfaction with hearing; two thirds of the patients were satisfied with their aids and used them regularly. The rest were dissatisfied and used them less than once a week. The aids were most systematically used to watch TV. Pure-tone average and handicap scaling were compared as guidelines for hearing-aid fitting. The most powerful tool to identify those in need of hearing-aids was handicap scaling based on interviews concerning self-assessed hearing difficulties.
We carried out an audiological survey of 204 officers at an infantry regiment in southern Sweden. The officers were exposed to impulse noise from firearms with peak levels up to 185 dB (SPL). The audiological measurement results were summarized in four age-groups, all of which showed significant hearing loss compared to ISO 1999 (1990) database A of a non-noise-exposed male population. Even officers who claimed regular use of hearing protectors during their entire military career showed these significant hearing losses. In the survey we also studied the association of the hearing thresholds with subjective exposure to heavy detonations and the annoyance of tinnitus. We found a significant relation between exposure to heavy detonations and tinnitus.
Testing the hearing abilities of marine mammals under water is a challenging task. Sample sizes are usually low, thus limiting the ability to generalize findings of susceptibility towards noise influences. A method to measure harbor porpoise hearing thresholds in situ in outdoor conditions using auditory steady state responses of the brainstem was developed and tested. The method was used on 15 live-stranded animals from the North Sea during rehabilitation, shortly before release into the wild, and on 12 wild animals incidentally caught in pound nets in Denmark (inner Danish waters). Results indicated that although the variability between individuals is wide, the shape of the hearing curve is generally similar to previously published results from behavioral trials. Using 10-kHz frequency intervals between 10 and 160 kHz, best hearing was found between 120 and 130?kHz. Additional testing using one-third octave frequency intervals (from 16 to 160?kHz) allowed for a much faster hearing assessment, but eliminated the fine scale threshold characteristics. For further investigations, the method will be used to better understand the factors influencing sensitivity differences across individuals and to establish population-level parameters describing hearing abilities of harbor porpoises.
After intensive, long-term musical training, the auditory system of a musician is specifically tuned to perceive musical sounds. We wished to find out whether a musician's auditory system also develops increased sensitivity to any sound of everyday life, experiencing them as noise. For this purpose, an online survey, including questionnaires on noise sensitivity, musical background, and listening tests for assessing musical aptitude, was administered to 197 participants in Finland and Italy. Subjective noise sensitivity (assessed with the Weinstein's Noise Sensitivity Scale) was analyzed for associations with musicianship, musical aptitude, weekly time spent listening to music, and the importance of music in each person's life (or music importance). Subjects were divided into three groups according to their musical expertise: Nonmusicians (N = 103), amateur musicians (N = 44), and professional musicians (N = 50). The results showed that noise sensitivity did not depend on musical expertise or performance on musicality tests or the amount of active (attentive) listening to music. In contrast, it was associated with daily passive listening to music, so that individuals with higher noise sensitivity spent less time in passive (background) listening to music than those with lower sensitivity to noise. Furthermore, noise-sensitive respondents rated music as less important in their life than did individuals with lower sensitivity to noise. The results demonstrate that the special sensitivity of the auditory system derived from musical training does not lead to increased irritability from unwanted sounds. However, the disposition to tolerate contingent musical backgrounds in everyday life depends on the individual's noise sensitivity.
The objective of this study was to evaluate the influence of atherogenic risk factors on hearing thresholds. In a cross-sectional study we analyzed data from a Danish survey in 2009-2010 on physical and psychological working conditions. The study included 576 white- and blue-collar workers from children's day care units, financial services and 10 manufacturing trades. Associations between atherogenic risk factors (blood lipids, glycosylated hemoglobin, smoking habits, body mass index (BMI), and ambulatory blood pressure) and hearing thresholds were analyzed using multiple linear regression models. Adjusted results suggested associations between smoking, high BMI and triglyceride level and low high-density lipoprotein level and increased low-frequency hearing thresholds (average of pure-tone hearing thresholds at 0.25, 0.5 and 1 kHz). Furthermore, an increasing load of atherogenic risk factors seemed associated with increased low-frequency hearing thresholds, but only at a borderline level of statistical significance. Associations were generally strongest with hearing levels of the worst hearing ear. We found no statistically significant associations between atherogenic risk factors and high-frequency hearing thresholds (average of pure-tone hearing thresholds at 4, 6 and 8 kHz).
There are only a few population-based epidemiological studies on audiogram configurations among adults. The aim of this study was to investigate the prevalence of different audiogram configurations among older adults. In addition, audiogram configurations among subjects reporting hearing problems were examined.
Cross-sectional, population-based, unscreened epidemiological study among older adults.
The subjects (n = 850), aged 54-66 years, were randomly sampled from the population register. A questionnaire survey, an otological examination, and pure-tone audiometry were performed.
The most prevalent audiogram configuration among men was high-frequency steeply sloping (65.3% left ear, 51.2% right ear) and among women, high-frequency gently sloping (33.0% left ear, 31.5% right ear). There were significantly more flat configurations among women than among men. Unclassified audiograms were common especially among women (17.5%). Subjects reporting hearing difficulties, difficulties in following conversation in noise, or tinnitus, more often had a high-frequency steeply sloping configuration than those not reporting.
High-frequency sloping audiogram configurations were common among older adults, and a high-frequency steeply sloping configuration was common among those reporting hearing problems.