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Computer scientists are increasingly aware of the power of ubiquitous computing systems that can display information in and about the user's environment. One sub category of ubiquitous computing is persuasive ambient information systems that involve an informative display transitioning between the periphery and center of attention. The goal of this ambient technology is to produce a behavior change, implying that a display must be informative, unobtrusive, and persuasive. While a significant body of research exists on ambient technology, previous research has not fully explored the different measures to identify behavior change, evaluation techniques for linking design characteristics to visual effectiveness, nor the use of short-term goals to affect long-term behavior change. This study uses the unique context of noise-induced hearing loss (NIHL) among collegiate musicians to explore these issues through developing the MIHL Reduction Feedback System that collects real-time data, translates it into visuals for music classrooms, provides predictive outcomes for goalsetting persuasion, and provides statistical measures of behavior change.

Made available in DSpace on 2016-04-27T18:11:48Z (GMT). No. of bitstreams: 1 Ana Ligia Melo Martins Greca.pdf: 460056 bytes, checksum: b44d71bbbac35e1535f5b80186a51c22 (MD5) Previous issue date: 2010-12-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Objective. Evaluate the knowledge of workers exposed to noise in relation to hearing protection and identify prevalence and outbreaks of noiseinduced hearing loss over three years. Method. The sample consisted of 65 workers at an engineering company aged 21 to 57 years, all male and exposed to noise at or above 85 dB (A). All workers wore hearing protection. The procedures included the use of the questionnaire "Beliefs and attitudes about hearing protection and hearing loss" and analysis of audiometric tests performed in 2007, 2008 and 2009. Results: Most workers (70.8%) had a time of noise exposure in the company within one to five years. Of the total, 33 workers (50.7%) reported complaints regarding the use of hearing protectors. The most frequent complaints were itching (23.1%) and difficulty in communication (12.3%). Most workers (78.5%) reported working in noisy environment. The prevalence of noise-induced hearing loss ranged from 21.6% to 38.5% during the three years. The onset of hearing loss ranged from 23 to 38.5% in the comparison of tests from 2007 to 2009. The questionnaire answers indicated, in most cases, workers attached importance to the hearing and know the strategies of hearing protection. Conclusion: There was a statistically significant association between age and hearing loss. The questionnaire results indicated that, in general, workers have knowledge about hearing protection, despite the high prevalence rate and triggering noise-induced hearing loss / Objetivo. Avaliar o conhecimento de trabalhadores expostos a ruído em relação à proteção auditiva e identificar prevalências e desencadeamentos de perda auditiva induzida por ruído no decorrer de três anos. Método. A amostra foi composta por 65 trabalhadores de uma empresa de engenharia com idade de 21 a 57 anos, todos do sexo masculino e expostos a ruído igual ou superior a 85 dB(A). Todos os trabalhadores usavam protetores auditivos. Os procedimentos incluíram a aplicação do questionário Crenças e atitudes sobre proteção auditiva e perda auditiva e análise das audiometrias realizadas em 2007, 2008 e 2009. Resultados: A maioria dos trabalhadores (70,8%) tinha tempo de exposição a ruído na empresa no intervalo de um a cinco anos. Do total, 33 trabalhadores (50,7%) relataram queixas em relação ao uso de protetor auditivo. As queixas de maior ocorrência foram coceira (23,1%) e dificuldade de comunicação (12,3%). A maioria dos trabalhadores (78,5%) relatou trabalhar em ambiente ruidoso. A prevalência de perda auditiva induzida pelo ruído variou de 21,6% a 38,5% no decorrer dos três anos. O desencadeamento de perdas auditivas variou de 23 a 38,5% na comparação dos exames de 2007 a 2009. As respostas do questionário indicaram, em sua maioria, que os trabalhadores atribuíam importância à audição e conheciam as estratégias de proteção auditiva. Conclusão: Houve associação estatisticamente significante entre idade e perda auditiva. Os resultados do questionário indicaram que, em geral, os trabalhadores têm conhecimento com relação à proteção auditiva, apesar do elevado índice de prevalência e de desencadeamento de perdas auditivas induzidas por ruído

Previous literature has demonstrated that supplemental magnesium may have a prophylactic effect on noise induced hearing loss (NIHL). The purpose of this study was to replicate the findings of a previous investigation concerning the beneficial effects of supplemental magnesium on TTS in humans. Forty participants with normal hearing were divided into two groups, experimental and control. The experimental group received a single, 150 mg dose of supplemental magnesium and the control group received a placebo. After an hour in a quiet environment, all participants were exposed to a narrowband noise centered at 2000 Hz and presented at 105 dB SPL. Audiometric thresholds were measured for the frequency range 250 Hz - 8000 Hz prior to the noise exposure, and then immediately, 30 minutes, and 60 minutes post-noise exposure. Both groups experienced TTS at and above 2000 Hz. The largest TTS was observed immediately following the noise exposure in both groups. There was no significant difference in TTS between the experimental group and the control group. It was concluded that a single dose of 150 mg of supplemental magnesium was not effective in reducing or preventing TTS.

Previous studies have shown that supplemental magnesium administered prior to exposure to noise has an alleviating effect on temporary threshold shift (TTS). These studies have only used audiometric thresholds to demonstrate changes in the auditory system. However, to help determine the effects on outer hair cells (OHCs), a more sensitive measure should be used. The purpose of this study was to determine if supplemental magnesium administration prior to noise exposure has a beneficial effect on acoustic overexposure using a double-blind research design. This was determined by measuring distortion product otoacoustic emissions (DPOAEs) to determine any changes in cochlear OHC function. DPOAE amplitude and signal-to-noise ratio (SNR) measurements were analyzed for two groups of twenty participants (an experimental group and a control group). The experimental group received 150 mg of magnesium gluconate one hour prior to noise exposure. The control group received a placebo pill that was identical in appearance to the magnesium pill. Following noise exposure, the greatest changes in DPOAE amplitude and SNR occurred for the frequencies that were one-half to one octave above the frequency of the stimuli used. The greatest changes in DPOAE measurements were present immediately post TTS-inducing stimulus, with only slight changes present after 30 minutes and no difference between 30 minutes and 60 minutes post-exposure. These results were the same for both groups. It was concluded that this dosage of supplemental magnesium had no apparent protective effect on DPOAEs following intense noise exposure.

A hearing impairment is primarily diagnosed by measuring the hearing thresholds at a range of auditory frequencies (air-conduction audiometry). Although this clinical procedure is simple, affordable, reliable and fast, it does not offer differential information about origins of the hearing impairment. The main goal of this thesis is to quantitatively link specific cochlear pathologies to certain changes in the spectral and temporal characteristics of the auditory system. This can help better understand the underlying mechanisms associated with sensorineural hearing impairments, beyond what is shown in the audiogram. Here, an electromechanical signal-transmission model is devised in MATLAB where the parameters of the model convey biological interpretations of mammalian cochlear structures. The model is exploited to simulate the cell-level cochlear pathologies associated with two common types of sensorineural hearing impairments, 1: presbyacusis (age-related hearing impairment) and, 2: noise-induced hearing impairment. Furthermore, a clinical study, consisting of different psychoacoustic and physiological tests, was performed to trace and validate the model predictions in human. The results of the clinical tests were collated and compared with the model predictions, showing a reasonable agreement. In summary, the present model provides a biophysical foundation for simulating the effect of specific cellular lesions, due to different inner-ear diseases and external insults, on the entire cochlear mechanism and thereby on the whole auditory system. This is a multidisciplinary work in the sense that it connects the ‘biological processes’ with ‘acoustic modelling’ and ‘clinical audiology’ in a translational context.

Thesis (Doctoral)--Uppsala University, 1983. / Includes bibliographical references (p. 33-34).

This study aimed to investigate the effectiveness of the Quiet earplug noise protectors worn by a group of South African industrial workers exposed to excessive noise in the workplace. This was achieved by investigating the prevalence and amplitudes of distortion product otoacoustic emissions (DPOAEs), as they have been found to be sensitive to the effects of noise on the cochlea (Vinck, Van Cauwenberge, Leroy,&Corthals, 1999, p. 52). DPOAEs were recorded before and after noise exposure and were compared in order to determine whether the earplugs are providing sufficient protection against cochlear damage. DPOAEs were recorded using a test protocol where the primaries are fixed at L1 = 60dB SPL and L2 = 35dB SPL (L1 - L2 = 25dB) with an f2/f1 ratio of 1.18. The f2 frequencies were selected to correspond closely to the audiometric test frequencies of 2000Hz, 3000Hz, 4000Hz, 6000Hz and 8000Hz. The study found the prevalence of DPOAEs to be statistically stable and repeatable. This was true for DPOAEs measured successively during the same test sitting, as well as comparing prevalence determined before and after exposure to eight hours of noise. DPOAE prevalence alone was therefore not found to be a good indication of the temporary threshold shift (TTS) associated with the effects of noise on the cochlea. However, a significant finding of the study was that normal DPOAEs were recorded in only six right ears (24%) and seven left ears (28%) before noise exposure, even though all the subjects presented with hearing thresholds better than 25dB SPL. This may mean that cochlear pathology is already evident in some of the subjects tested. Further results of the study showed DPOAE amplitudes to be sensitive to the negative effects of excessive noise, as there was a significant difference between DPOAE amplitudes measured before and after the noise exposure. DPOAE amplitudes, specifically in the frequencies that are known to be affected by noise such as 4000Hz and 6000Hz, measured after the work-shift were significantly smaller than those measured before exposure to noise. Although correct usage of the earplugs could not be controlled for the duration of the noise exposure, each subject was instructed on the correct usage of the hearing protection before entering the noise zone. Bearing this limitation of the study in mind, because DPOAE amplitudes were reduced the implication is that the Quiet earplugs are not providing sufficient protection against the harmful effects of noise. / Dissertation (M (Communication Pathology))--University of Pretoria, 2005. / Speech-Language Pathology and Audiology / Unrestricted

Noise induced hearing loss has been extensively researched and commented on, yet it remains prevalent among industrial workers. The real-world attenuation properties of the Noise Clipper® custom-made hearing protection device and the comfort levels it afford are unknown. Furthermore, research in hearing conservation is seldom focused on the critical/biological thresholds for temporary threshold shift. Field studies on hearing protection devices have demonstrated that laboratory derived measures bear little relation to attenuation achieved in workers. Research has consistently demonstrated that noise reduction ratings that are derived from the laboratory real-ear-at-threshold method do not accurately represent the attenuation of noise that these devices actually provide and the matter remains unclear. Too many important variables are neglected in current real-ear-atthreshold evaluation protocols. This study used an alternative method, the microphone-inreal- ear approach where a dual-element microphone probe was inserted into the Noise Clipper® to measure noise reduction by recording the difference in noise levels outside and behind the device. The sub aims of the study were to record ambient noise levels and frequency spectra; to determine the attenuation characteristics; and to compare the attenuation thresholds to biological thresholds for temporary threshold shift. Using this protocol, measurements were made on 20 subjects in real world situations in order to match the attenuation characteristics of the Noise Clipper® to the actual noise exposure. The microphone-in-real-ear derived attenuation thresholds were compared to the real-earat- threshold values provided by the manufacturer of the Noise Clipper®. Additional subaims were to determine the comfort levels of the Noise Clipper® and record the selfreported wearing time of the device. Wearing comfort was evaluated using a bipolar rating scale. The researcher interviewed 240 mine workers at a platinum mine. Several comfort related sub-scales were used to quantify reported comfort levels. Simultaneously, usage time of the device was self-reported by each worker. Results of the microphone-in-real-ear measurements indicated that ambient noise levels fluctuated from day to day. The attenuation results indicated that most of the measurements suggested protection against noise induced hearing loss through the use of the Noise Clipper®. It was found that the REAT results over estimated the attenuation ability of the Noise Clipper® when compared to the results of the F-MIRE measurements. Eighty seven percent of the measurements indicated protection from thresholds below the biological threshold for temporary threshold shift. Seventy five percent of the workers indicated that the Noise Clipper® was comfortable to wear and 79% indicated that they used it for a full eight hour shift. The results provide an opportunity to assess the use of a protection device and its effectiveness among mineworkers combined with information regarding noise exposure levels. The findings highlight the importance of evaluating variability in terms of individual-specific protection. / Dissertation (MCommunication Pathology)--University of Pretoria, 2013. / Speech-Language Pathology and Audiology / unrestricted