Hearing loss can significantly hinder an individual's ability to engage socially and, when left untreated, can lead to anxiety, depression, and even dementia. The most common type of hearing loss is sensor-neural hearing loss that is treated using hearing aids (HAs). However, a significant fraction of individuals that may benefit from using HA do not use them and, the satisfaction of those that do, is only around 60%. Today, we have only a limited understanding regarding the factors that contribute to the low adoption and satisfaction rates. This is a limitation of existing laboratory-based assessment methods that cannot accurately predict the performance of HAs in the real-world as they do not fully reproduce the complexities of real-world environments. There four core contributions of my PhD thesis: i) the development new computer-based methods for assessing HAs in the real-world. Our approach is based on the insight that HA performance is intrinsically dependent on the context in which a HA is used. A context includes characteristics of the listening activity, social context, and acoustic environment. To evaluate this hypothesis, we have developed AudioSense, a system that uses mobile phones to jointly characterize the context of users and the performance of HAs. ii) We provide the first instance of characterization of the auditory lifestyle of hearing aid users, and the relationships that exist between the context and hearing aid outcomes. iii) We utilize the subjective data collected using AudioSense to build novel models that can predict the success of hearing aid prescriptions for new and experienced users. We also quantitatively prove the importance of collecting contextual information for evaluating hearing aids. iv) We use the objective audio data collected with AudioSense to predict contextual information like acoustic activity and noise level. This provides us a way to intelligently infer contextual information automatically and reduce the burden on the study participants.

Objective: This study investigated the perspectives of adults with hearing impairment on hearing help-seeking and rehabilitation. Design: Individual semi-structured interviews were completed. Study sample: In total, 34 adults with hearing impairment in four countries (Australia, Denmark, UK, and USA) participated. Participants had a range of experience with hearing help-seeking and rehabilitation, from never having sought help to being satisfied hearing-aid users. Results: Qualitative content analysis identified four main categories (perceiving my hearing impairment, seeking hearing help, using my hearing aids, and perspectives and knowledge) and, at the next level, 25 categories. This article reports on the densest categories: they are described, exemplified with interview quotes, and discussed. Conclusions: People largely described hearing help-seeking and rehabilitation in the context of their daily lives. Adults with hearing impairment rarely described clinical encounters towards hearing help-seeking and rehabilitation as a connected process. They portrayed interactions with clinicians as isolated events rather than chronologically-ordered steps relating to a common goal. Clinical implications of the findings are discussed. / <p>Funding Agencies|University of Queensland Graduate School||</p>

A speech visualization system is proposed thatcould be used by a deaf person for understanding speech.Several novel techniques are proposed, including: (1) Minimizing spectral leakage in the Fourier transform by using avariable-length window. (2) Making use of the fact that there is no spectral leakage in order to calculate how much of the energy of the speech signal is due to its periodic component vs. its nonperiodic component. (3) Modelling the mouth and lips as a band-pass filter and estimating the central frequency and bandwidth of this filter in order to assign colours tounvoiced speech sounds.

Idag finns få studier gällande könsskillnader inom hörselvården, däremot finns forskning inom andra vårdområden. Hörselvården består bland annat av rehabilitering, där den tekniska hörselrehabiliteringen är en stor del. Den innefattar främst utprovning av hörapparater och hörseltekniska hjälpmedel.    Syftet med denna studie är att undersöka om det finns några skillnader mellan män och kvinnor gällande den tekniska hörselrehabiliteringen.    Metoden för studien är kvantitativ och deskriptiv. En journalgenomgång inom ett enskilt landsting genomfördes. Totalt ingick patientjournaler för 56 personer i undersökningen. Av dessa var 27 kvinnor och 29 män. Vid journalgenomgången användes ett protokoll där olika punkter gällande patientens förutsättningar och behov togs upp.    Resultatet visar inga tydliga skillnader avseende kön gällande den tekniska hörselrehabiliteringen. Det finns dock tendenser till att fler kvinnor får en unilateral hörapparatanpassning jämfört med män. Resultatet visar att få avancerade hörapparater och hörseltekniska hjälpmedel förskrivits till patienter. Patienternas behov enligt rehabiliteringsplanen varierade mycket och ingen skillnad kunde ses gällande hörapparatsegment varken inom könen eller när könen jämfördes med varandra.    Inga märkbara skillnader i den tekniska hörselrehabiliteringen kunde hittas mellan könen. Mer forskning skulle behövas på området, både gällande hörapparatsegment samt vilka hörseltekniska hjälpmedel som förskrivs och varför. Även en liknande studie med ett större urval skulle behövas.

The focus of this study is the optoelectronic integration of a micro-optical displacement detection architecture with a biomimetic MEMS microphone membrane based on the directional hearing mechanism of the parasitic fly Ormia Ochracea. The micromachined microphones feature optical interferometric displacement detection achieved using a commercially available Vertical Cavity Surface Emitting Laser (VCSEL) coupled with a custom designed silicon photodiode array. This design is shown to have significant advantages over conventional hearing aid microphones, which employ capacitive detection. A Multi-Chip Module (MCM) optoelectronic package is designed to integrate the biomimetic membrane with the optical displacement detection electronics in order to produce a fully integrated acoustic sensor. The modular package components, which are fabricated using high resolution stereolithography apparatus (SLA) equipment, provide accurate optical alignment of the optoelectronic components and allow complete device integration in a package with a total volume under 0.5cc. Characterization of the integrated microphones is described in detail, including measurements of sensitivity, noise floor and directivity. A displacement resolution of 3.5x10⁻¹³ m/√Hz was measured between 4kHz and 16kHz in an anechoic test chamber, corresponding to a dynamic range of 115dB for the optical detection architecture. The total noise SPL of the device is 35.9dBA. Unlike capacitive microphones with similar noise levels, the device developed in this work exhibits first order dipole directivity patterns between 250Hz-1kHz, with an ideal Directivity Index of 4.8dB @ 1kHz and directional attenuation exceeding 25dB. With these results the optoelectronic package presented in this work demonstrates the viability of the integrated optical biomimetic microphones in compact, low power applications, specifically directional hearing aids.

Hearing aids are tasked with the undesirable job of compensating an impaired, highly-nonlinear auditory system. Historically, these devices have either employed linear processing or relatively unsophisticated, nonlinear processing techniques. With increasingly more accurate models of the auditory system, expanding computational power, and many more objective measures which utilize these models, we are at a turning point in hearing aid design. Although subjective listener tests are often the most accepted methods for evaluating the quality and intelligibility of speech, they inherently treat the auditory system as a "black box." Conversely, model-based objective measures typically treat the auditory system as a cascade of physical processes. As a result, objective measures have the potential to provide more detailed information about how sound is processed and about where and why quality or intelligibility breaks down. Provided that we can generalize model-based objective measures, we can use the measures as tools for understanding how to best process degraded signals, and therefore, how to best design hearing aids. However, generalizability is a key requirement. Since many of the well-known objective measures have been developed for normal-hearing listeners in the context of audio codecs, we are unsure about the generalizability of these measures to predicting quality and intelligibility for hearing-impaired listeners with "unknown" datasets (i.e. a set on which it was not trained) and distortions which are specific to hearing aids. Relatively recently, however, Kates and Arehart (Journal of the Audio Engineering Society, 2010) proposed the Hearing Aid Speech Quality Index (HASQI), which is a model-based objective measure that predicts quality for normal-hearing and hearing-impaired listeners by taking into account many of the distortions which hearing aids introduce. HASQI solves many of our concerns of generalizability for predicting quality, but it still remains to test HASQI's ability to predict quality with datasets on which it was not trained. Thus, we explore the robustness of HASQI by testing its ability to predict quality for "unknown" de-noised speech, and we directly compare its performance to some other metrics in the literature.

Professional research project (Au.D.)--University of South Florida, 2002. / Title from PDF of title page. / Document formatted into pages; contains 34 pages. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: The self-perceived hearing aid benefit of 38 participants was examined. Of the 38 subjects, 8 were found to have an auditory processing disorder as measured by the Dichotic Sentence Identification (DSI). When compared to the non-APD subjects, there were essentially no significant differences on the APHAB or COSI outcome measures. However, two of the 5 scales of the CHPI did show significant differences. In conclusion, these results do not support the notion of APD having a negative effect on hearing aid benefit. No finding in this study was robust and although there were several trends supporting that APD may impede an individual from receiving their full potential of benefit, this finding is not necessarily so. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

Thesis (M. Communication Pathology)--University of Pretoria, 2009. / Includes bibliographical references.

Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Hasler, Paul; Committee Co-Chair: Degertekin, Levent; Committee Member: Anderson, David; Committee Member: Ayazi, Farrokh; Committee Member: Brand, Oliver; Committee Member: Hesketh, Peter. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Clear speech refers to a speaking style that is more intelligible than typical, conversational speaking styles. It is usually produced at a slower rate compared to conversational speech. Clear speech has been shown to be more intelligible than conversational speech for a large variety of populations, including both hearing impaired (Schum, 1996; Picheny, Durlach, & Braida, 1985; and Payton, Uchanski, & Braida, 1994) and normal hearing individuals (e.g. Uchanski, Choi, Braida, Reed, & Durlach, 1996) under a variety of conditions, including those in which presentation level, speaker, and environment are varied. Although clear speech is typically slower than normally produced conversational speech, recent studies have shown that it can be produced at normal rates with training (Krause & Braida, 2002). If clear speech at normal rates is shown to be as effective for individuals with hearing loss as clear speech at slow rates, it would have both clinical and research implications. The purpose of this study was to determine the effectiveness of clear speech at normal rates for older individuals with hearing loss. It examined the way in which intelligibility, measured as percent correct keyword scores on nonsense sentences, varied as a result of speaking mode (clear versus conversational speech) and speaking rate (slow versus normal) in six adults aged 55-75 years old with moderate, sloping, hearing loss. Each listener was presented with nonsense sentences in four speech conditions: clear speech at slow rates (clear/slow), clear speech at normal rates (clear/normal), conversational speech at slow rates (conv/slow), and conversational speech at normal rates (conv/normal) read by four different talkers. Sentences were presented monaurally in quiet to the listeners via headphones. Results indicated that clear/slow speech was the most intelligible condition overall. Neither conv/slow nor clear/normal provided an intelligibility benefit relative to conv/normal speech on average, suggesting that for older adults with moderate, sloping hearing loss, the combination of using clear speech and a slower speaking rate is more beneficial to intelligibility than the additive effects of altering either speaking rate or speaking mode alone. It has been suggested previously (Krause, 2001) that audiological characteristics may contribute to the lack of clear/normal benefit for certain listeners with hearing loss. Although clear/normal speech was not beneficial on average to listeners in this study, there were cases in which the clear/normal speech of a particular talker provided a benefit to a particular listener. Thus, severity and configuration of hearing loss alone cannot fully explain the degree to which listeners from hearing loss do (or do not) benefit from clear/normal speech. More studies are needed to investigate the benefits of clear/normal speech for different audiological configurations, including individuals with flat losses. In addition, the listening tasks should include more difficult conditions in order to compensate for potential ceiling effects.