Background: For many young people, exposure to music from personal audio system use may represent a significant component of daily noise dose. Moreover, there is increasing concern for the hearing of those who listen at high volumes. The purpose of this study was to determine the noise levels experienced on commuter buses, and to investigate how these impact on the volume-setting behavior of young adult personal audio system users. Methods: A questionnaire was used to probe transport use, personal audio system-listening behaviors and the extent of understanding about noise-induced hearing loss. The influence of bus noise on volume-setting behavior was determined by measuring, in a lab setting, the sound-level preferences of participants when listening to their favorite song, a generic song, or a podcast in the absence and presence of various levels of bus noise, simulated using output-adjusted recordings made of bus noise. Statistical analysis was conducted using analysis of variance. Results: While the bus noise itself was below 85 dB Leq, as the sound level of the buses increased, so did the percentage of commuters who were found to exceed the equivalent of 8 hours of exposure at 85 dB Leq. Implications: Investment in buses with lower noise levels or the use of noise-canceling or noise-occluding headphones would help to reduce the likelihood of noise-induced hearing loss for bus commuters.

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Background: Previous studies have highlighted that bilingual listeners have a deficit in speech perception in their second language compared with monolingual listeners in noisy listening environments. This deficit may give rise to educational and occupational implications for bilingual speakers who are studying or working in non-native language environments in poor acoustic conditions. Objectives: To compare the speech perception performance of monolingual English speakers and English as a second language (ESL) bilinguals within environments with various levels of background noise and to examine whether bilinguals with an early age of second language acquisition would perform better than those with a late age of acquisition. Study sample: Two groups of adult listeners with normal hearing participated: monolingual British English listeners (N = 15) and bilingual Arabic listeners for whom English was their second language and who were proficient in English (N = 15). The quick speech-in-noise (QuickSIN) test was used to assess signal-to-noise ratio (SNR) loss and SNR-50 for both groups. Results: The QuickSIN test results indicated that bilingual Arabic listeners with normal hearing displayed a mild SNR loss comparable to that observed for a person with hearing loss, indicating a higher SNR needed for this population to achieve a comparable level of comprehension to their monolingual English peers. Conclusion: Results highlight the importance of measuring SNR loss to obtain accurate diagnosis and potential rehabilitative information that is not available from audiogram studies.

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Background: The effects of noise on sleep and health have been evaluated in earlier studies using noise indices chosen on the basis of practical considerations and not on the physiologic mechanisms of sleep disturbance due to noise exposure. We investigated the neurophysiologic mechanisms of sleep and found that the arithmetic mean of the sound levels above a threshold ([INSIDE:1]) may be used effectively to evaluate the effects of nighttime noise exposure. However, the efficacy of using [INSIDE:2] has only been confirmed in a specific setting; therefore, the reliability of [INSIDE:3] in other situations should be investigated by applying it in epidemiologic studies. In this study, we aimed to obtain an alternative equation for calculating [INSIDE:4] from existing noise indices, given that detailed information on fluctuations in sound levels, needed to calculate [INSIDE:5] according to the definition, is not readily available. Materials and Methods: We examined statistical relationships among noise indices namely [INSIDE:6], the number of noise events above 60 and 70 dB (N₆₀ and N₇₀), and the night equivalent sound level (L_night). The study area was around the Kadena military airfield, where the sound levels were recorded at noise monitoring stations. Results: [INSIDE:7] showed a very strong correlation with N₆₀ and N₇₀ but not with L_night. Among regression equations, an equation representing N₆₀ and the interaction between N₆₀ and L_night, which is equivalent to the product of N₆₀ and a linear expression of L_night, showed the highest prediction capability. Conclusion: We obtained a regression equation to calculate [INSIDE:8] from N₆₀ and L_night. Although this alternative equation for [INSIDE:9] is only applicable for military aircraft noise, it will aid the re-analysis of existing epidemiologic studies as well as further investigations on the relationship between noise exposure and health effects.

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Objective: We made hypotheses that tinnitus will appear more likely in patients with sudden deafness with superior hearing in unaffected ear or with more severe acute hearing loss. Methods: A retrospective cohort study was performed. Five hundred forty-one patients were identified with idiopathic sudden sensorineural hearing loss (ISSHL) from January 1995 to August 2006. The exclusion criteria for this study were as follows: bilateral sudden hearing loss and Meniere disease, previous tinnitus or bilateral tinnitus at initial evaluation, and onset of hearing loss less than 7 days. The cohort enrolled 454 patients. The enrolled patients were classified into two groups: patient with acute onset tinnitus in the affected ear and patients without tinnitus at initial visit. Main outcome measures were patient age, the presence or absence of vertigo and tinnitus, audiometric patterns, the severity of hearing loss, and hearing in the unaffected ear. Results: Better contralateral hearing (n = 220 versus n = 72, P < 0.001) and younger age (48 versus 55 years, P < 0.001) were independently associated with the acute onset of tinnitus in patients with ISSHL. The degree of asymmetry between the ears did not differ significantly between patients with and without tinnitus. The sex, presence of vertigo, shape of audiogram, and severity of hearing loss were not correlated with tinnitus occurrence. Conclusions: Tinnitus triggered by ISSHL was more frequent in patients with better contralateral hearing and of a younger age, irrespective of the severity of hearing loss on the affected side or the asymmetry between the ears.

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