Representation of amplified speech at cortical level in good and poor hearing aid performers / Representação da fala amplificada ao nível cortical em bons e maus usuários de aparelhos auditivos

Abstract Introduction: Hearing aid users reject their own hearing aid because of annoyance with background noise. The reason for dissatisfaction is located anywhere from the hearing aid microphone to the integrity of neurons along the auditory pathway. In this preview, the output of hearing aid was recorded at the level of ear canal and at auditory cortex in good and poor hearing aid users, who were classified using acceptable noise level. Objective: To study the representation of amplified speech in good and poor hearing aid performers. Methods: A total of 60 participants (age ranged 15-65 years) with moderate bilateral sensorineural hearing impairment grouped into good (n = 35) and poor (n = 25) hearing aid performers. Gap detection test and aided SNR 50 were administered. In addition, ear canal acoustic measures and cortical auditory evoked potentials were recorded in unaided and aided conditions at 65 dB SPL. Results: Hearing aid minimally alters temporal contrast of speech reflected in envelope difference index. Although having similar temporal impairment, acoustic characteristics of amplified speech sounds and SNR 50 scores from both groups, the aided cortical auditory evoked potentials surprisingly showed significant earlier latencies and higher amplitudes in good performers than poor performers. In addition, good and poor performers classified based on annoyance level was predicted by latencies of 2N1 and 2P2 components of acoustic change complex. Further, a follow-up revealed hearing aid use has relation with acceptance towards noise. Conclusion: Participants who are willing to accept noise from those who are not willing to accept noise have subtle physiological changes evident at the auditory cortex, which supports the hearing aid usage.

Resumo Introdução: Usuários de aparelhos auditivos rejeitam seu próprio aparelho pelo incômodo relacionado ao ruído de fundo. O motivo da insatisfação varia desde o microfone do aparelho auditivo até a integridade dos neurônios ao longo da via auditiva. Nesta análise prévia, a saída da prótese auditiva foi registrada no nível do meato auditivo externo e no córtex auditivo em bons e maus usuários de prótese auditiva, que foram classificados com um nível de ruído aceitável. Objetivo: Estudar a representação da fala amplificada em bons e maus usuários de aparelhos auditivos. Método: Foram examinados 60 participantes (de 15 a 65 anos) com deficiência auditiva neurossensorial bilateral moderada divididos em bons (n = 35) e maus (n = 25) usuários de aparelhos auditivos. Teste de detecção de gap e SNR 50 assistido foi administrado. Além disso, as medidas acústicas do meato externo e os potenciais evocados auditivos corticais foram registrados em condições não assistida e assistida a 65 dB NPS. Resultados: O aparelho auditivo altera minimamente o contraste temporal da fala, refletido no envelope difference index. Embora tenham uma deficiência temporal similar, as características acústicas de sons de fala amplificados e escores do SNR 50 de ambos os grupos, os potenciais evocados auditivos corticais assistidos surpreendentemente demonstraram latências iniciais significativas e maiores amplitudes em bons do que em maus usuários. Além disso, os bons em comparação com os maus usuários, classificados com base no nível de incômodo, foram previstos pelas latências dos componentes 2N1 e 2P2 do complexo de alteração acústica. Além disso, os resultados do seguimento revelaram que o uso de aparelhos auditivos têm relação com a aceitação do ruído. Conclusão: Os participantes dispostos a aceitar o ruído, quando comparados com aqueles que não estão dispostos a aceitá-lo, apresentam evidência de sutis alterações fisiológicas no córtex auditivo, que apoiam o uso da prótese auditiva.

The Effect of Digital Noise Reduction on Annoyance and Speech Perception in Low and High Acceptable Noise Level Groups

Introduction: Studies have reported that although speech perception in noise was unaltered with and without digital noise reduction (DNR), the annoyance toward noise measured by acceptable noise level (ANL) was significantly improved by DNR with the range between 2.5 and 4.5 dB. It is unclear whether a similar improvement would be observed in those individuals who have an ANL ≥ 14 dB (predictive of poor hearing aid user) often rejects their aid because of annoyance toward noise. Objectives: (a) To determine the effect of activation of DNR on the improvement in the aided ANL from low- and high-ANL groups; and (b) to predict the change in ANL when DNR was activated. Method: Ten bilateral mild to severe sloping sensorineural hearing loss (SNHL) participants in each of the low- and high-ANL groups were involved. These participants were bilaterally fitted with receiver in canal (RIC) hearing aids (Oticon, Smorum, Egedal, Denmark) with a DNR processor. Both SNR-50% (Signal to noise ratio (in dB) required to achieve 50 % speech recognition) and ANL were assessed in DNR-on and DNR-off listening conditions. Results: Digital noise reduction has no effect on SNR-50 in each group. The annoyance level was significantly reduced in the DNR-on than DNR-off condition in the low-ANL group. In the high-ANL group, a strong negative correlation was observed between the ANL in DNR off and a change in ANL after DNR was employed in the hearing aid (benefit). The benefit of DNR on annoyance can be effectively predicted by baseline-aided ANL by linear regression. Conclusion: Digital noise reduction reduced the annoyance level in the high-ANL group, and the amount of improvement was related to the baseline-aided ANL value (AU)

Urine Cotinine Should Be Involved in Initial Evaluation of Tinnitus in Adolescents

OBJECTIVES: Smoking is associated with hearing loss, while the correlation between tinnitus and smoking is not fully elucidated. This study aimed to evaluate risk factors of tinnitus in adolescents in terms of smoking, and we identified a rectifiable parameter that can be serially monitored. METHODS: A cross-sectional study was conducted using data from the Korea National Health and Nutrition Examination Survey, with 2,782 participants aged 12 to 18 years, from 2008 through 2011. Participants with history of ear disease, hearing loss, and inadequate responses to questionnaires were excluded. We investigated the prevalence of tinnitus and tinnitus-related annoyance by questionnaire and sought potential risk factors in blood and urine tests and smoking history. RESULTS: The prevalence of tinnitus in the 12- to 18-year-old population was 17.5%, with 3.3% reporting tinnitus-related annoyance. On univariate analysis, the prevalence of tinnitus increased with age (P < 0.001) and was higher among girls (P=0.012). Blood tests and urinalysis showed significant correlation between tinnitus and red blood cell count, alkaline phosphatase levels, and urine cotinine (P=0.002, P < 0.001, P=0.018, respectively). In multivariate analysis, the urine cotinine level was the only parameter associated with tinnitus (odds ratio, 1.000; 95% confidence interval, 0.999 to 1.000; P=0.038). Smoking was also significantly correlated with tinnitus (P=0.043), and amount of smoking with tinnitus-related annoyance (P=0.045). However, current smoking and past smoking were not correlated with tinnitus. CONCLUSION: Urine cotinine may be a rectifiable marker for management of tinnitus in adolescents. This suggests that smoking cessation should be incorporated in the management of tinnitus in adolescents.

Annoyance-rate-and-casualty-reality-based method of comfort evaluation of military ambulance / 医疗卫生装备

Objective To explore an method for comfort evaluation of the military ambulance to enhance ride comfort during casualty transport. Methods The method executed quantitative evaluation of vibrational comfort by the existing vibration comfortableness evaluation ways for non-ambulatory casualty, different reactions of casualty to vibrational excitement and annoyance rate analysis based on psychophysics, which took considerations on the ratio of injured sites at war or natural disaster conditions as well as susceptibility analysis. Trials of the the method were carried out on the vibrational comfort analysis of some military ambulance during the road test.Results The method had feasibility for vibration comfortableness evaluation of non-ambulatory casualty,and improved the traditional ways in quantitative analysis.Conclusion The method gains advantages over the international ways, and contributes to the related researches on vibration reduction.

The responses of subjective feeling, task performance ability, cortisol and HRV for the various types of floor impact sound: a pilot study

BACKGROUND: Recently, noise coming from the neighborhood via floor wall has become a great social problem. The noise between the floors can be a cause of physical and psychological problems, and the different types of floor impact sound (FIS) may have the different effects on the human's body and mind. The purpose of this study is to assess the responses of subjective feeling, task performance ability, cortisol and HRV for the various types of floor impact. METHODS: Ten men and 5 women were enrolled in our study, and the English listening test was performed under the twelve different types of FIS, which were made by the combinations of bang machine (B), tapping machine (T), impact ball (I) and sound-proof mattress (M). The 15 subjects were exposed to each FIS for about 3 min, and the subjective annoyance, performance ability (English listening test), cortisol level of urine/saliva and heart rate variability (HRV) were examined. The sound pressure level (SPL) and frequency of FIS were analyzed. Repeated-measures ANOVA, paired t-test, Wilcoxon signed rank test were performed for data analysis. RESULTS: The SPL of tapping machine (T) was reduced with the soundproof mattress (M) by 3.9–7.3 dBA. Impact ball (I) was higher than other FIS in low frequency (31.5–125 Hz) by 10 dBA, and tapping machine (T) was higher than other FIS in high frequency (2–4 k Hz) by 10 dBA. The subjective annoyance is highest in the combination of bang machine and tapping machine (BT), and next in the tapping machine (T). The English listening score was also lowest in the BT, and next in T. The difference of salivary cortisol levels between various types of FIS was significant (p = 0.003). The change of HRV parameters by the change of FIS types was significant in some parameters, which were total power (TP) (p = 0.004), low frequency (LF) (p = 0.002) and high frequency (HF) (p = 0.011). CONCLUSIONS: These results suggest that the human's subjective and objective responses were different according to FIS types and those combinations.

Assessment Of Traffic Noise And The Association With Non Auditory Effect Among Shop Lot Workers In Kajang, Selangor

The objective of study is to determine traffic noise level and non-auditory effect among shop lot workers at Kajang Selangor. This cross sectional study was carried to study traffic noise exposure with annoyance and work performance level among shop lot workers in Jalan Mendaling, Jalan Tukang and Jalan Sulaiman at Kajang town, Selangor. This study involves 120 shop lot workers that exposed to the traffic noise during their working hours where they are randomly selected. Noise exposure was estimated using the Sound Level Meter for environmental noise. The traffic volume was recorded using video recorder and calculated using tally counter. One set questionnaire consist standard questionnaire was used to assess the annoyance level and work performance level among the respondents. Respondents were predominantly by male which are 94 and female, 26 respondents. The mean age of the respondent were ranged between 41 to 60 years old. Only 12.5% of respondent are ranged 21 until 30 years old. In total of 120 respondent, 54.2% of them are Chinese while Malay and India only 30% and 15.8% respectively. The result showed that the traffic noise level at study areas are exceeded the permissible sound limit of commercial and business area during daylight which is 70 dB(A). Regarding work performance, 94 respondents are having low work performance level and 82% of respondent high annoyance level during the exposure of traffic noise from four different sources which are noise from the traffic, speeding vehicle, high traffic volume and exhaust system. There is a significant relationship between traffic noise level with work performance level (p=0.001) and annoyance level (p=0.026). The average traffic noise (Laeq) level at Jalan Mendaling, Jalan Tukang and Jalan Sulaiman is 71.19 dB(A) which were high and exceeds permissible sound level from road traffic, commercial and business place at day time, 70 dB(A). The exposure from the traffic noise effect the annoyance level and work performance level among the shop lot worker. In order to reduce traffic noise exposure towards the shop lot workers, some recommendation are needed to control the traffic noise such as build a noise barrier, plant trees and also enforcement of legal requirement in noise level.

Investigation of Environmental Noise Perception of Residents in Lu'an City / 环境与健康杂志

Objective To understand the situation of, mental health and behavior of the residents influenced by the environment noise. Methods From Feb. till Mar. 2005 and from Sep. till Oct. 2006, the residents living in 4 functional districts in Lu'an city, Anhui Province for one year or more were investigated by questionnaire. The investigation involved the general status, noise perception, behavior, adjustability and so on. 952 available questionnaires from 84 sites were attained. Results The significant differences were seen in the environmental noise perception among sex, age, occupation and health status (P