The future of hearing aid technology

Background. Hearing aid technology has proven successful in the rehabilitation of hearing loss, but its performance is still limited in difficult everyday conditions characterized by noise and reverberation. Objectives. Introduction to the current state of hearing aid technology and presentation of the current state of research and future development. Methods. Current literature is analyzed and several specific new developments are presented. Results. Both objective and subjective data from empirical studies show the limitation of current technology. Examples of current research show the potential of machine-learning based algorithms and multi-modal signal processing for improving speech processing and perception, of using virtual reality for improving hearing device fitting and of mobile health technology for improving hearing-health services. Conclusions. Hearing device technology will remain a key factor in the rehabilitation of hearing impairment. New technology such as machine learning, and multi-modal signal processing, virtual reality and mobile health technology will improve speech enhancement, individual fitting and communication training

Exploring the use of speech in audiology: A mixed methods study

This thesis aims to advance the understanding of how speech testing is, and can be, used for hearing device users within the audiological test battery. To address this, I engaged with clinicians and patients to understand the current role that speech testing plays in audiological testing in the UK, and developed a new listening test, which combined speech testing with localisation judgments in a dual task design. Normal hearing listeners and hearing aid users were tested, and a series of technical measurements were made to understand how advanced hearing aid settings might determine task performance. A questionnaire was completed by public and private sector hearing healthcare professionals in the UK to explore the use of speech testing. Overall, results revealed this assessment tool was underutilised by UK clinicians, but there was a significantly greater use in the private sector. Through a focus group and semi structured interviews with hearing aid users I identified a mismatch between their common listening difficulties and the assessment tools used in audiology and highlighted a lack of deaf awareness in UK adult audiology. The Spatial Speech in Noise Test (SSiN) is a dual task paradigm to simultaneously assess relative localisation and word identification performance. Testing on normal hearing listeners to investigate the impact of the dual task design found the SSiN to increase cognitive load and therefore better reflect challenging listening situations. A comparison of relative localisation and word identification performance showed that hearing aid users benefitted less from spatially separating speech and noise in the SSiN than normal hearing listeners. To investigate how the SSiN could be used to assess advanced hearing aid features, a subset of hearing aid users were fitted with the same hearing aid type and completed the SSiN once with adaptive directionality and once with omnidirectionality. The SSiN results differed between conditions but a larger sample size is needed to confirm these effects. Hearing aid technical measurements were used to quantify how hearing aid output changed in response to the SSiN paradigm

Attitudes of Normal Hearing Listeners Towards Personal Sound Amplification Products: Sound World Solutions CS50

Over 23 million individuals in the United States have some degree of hearing loss but do not own hearing aids. Individuals may choose not to adopt hearing aid technology for an assortment of reasons, including the stigma associated with hearing aids, cost of the devices, or denying the effects of hearing loss. Prevalence of hearing aid usage remains low despite research indicating that untreated hearing loss is correlated with decreased quality of life and accelerated cognitive decline. In recent years, personal sound amplification products (PSAPs) have entered the market as simple, low cost, discreet devices in attempt to reach non-users of amplification. The purpose of this study was to determine if the Sound World Solutions CS50 PSAP affects speech understanding in noise in normal hearing adult listeners. Listening to speech in noise is difficult for a majority of those with hearing loss and an important situation the CS50 is marketed to help improve. Such claims, however, have not been substantiated. This study also examined the experience of these individuals with the CS50, including their attitudes on ease of use, comfort, and willingness to pay, via a brief questionnaire. Results of this study indicated that there is no significant difference in the speech recognition in noise scores of normal hearing listeners when they are unaided and when they are aided monaurally with the CS50 device. Overall, individuals judged the ease of inserting/removing the device, changing the battery, and changing the program and volume to be good to very good. Physical comfort, appearance of the device, sound quality, and benefit to speech understanding in noise were judged to be fair. A majority of individuals were somewhat unwilling to spend $200-$300 on this device should they require amplification. Lack of significance among speech in noise scores and fair judgments of many factors regarding the Sound World Solutions CS50 PSAP may have resulted from not truly assessing the device’s directional microphone and testing only normal hearing listeners who do not have as much need for an amplification device as an individual with hearing loss. Further testing on individuals with hearing loss may help determine of this device would benefit such a population