Date of Award

May 2024

Degree Type


Degree Name

Doctor of Philosophy


Biomedical and Health Informatics

First Advisor

Yi Hu

Committee Members

Weizhong Wang, Chiu Tai Law, Zeyun Yu, Jun Zhang


Hearing loss is a universal healthcare issue and if left untreated, it has been associated with multiple serious conditions such as depression, dementia, diabetes, cardiovascular disease, falls, social isolation etc. It has been estimated that approximately 15% of the adult population in the United States (which is estimated to be around 37.5 million) have reported some difficulty in hearing. Hearing Aids are the primary devices used to treat individuals with mild to moderate hearing loss. The National Institute on Deafness and Other Communication Disorders (NIDCD) estimates that about 28.8 million adults in the United States could benefit from using hearing aids. In the age group of 20-69, fewer than 1 in 6 individuals who could benefit from hearing aids have ever used the device. Typically, audiologist sourced hearing aids are the main source of treatment. It’s been scientifically and clinically validated that the established process used by audiologists works, but there are several problems with this solution. On average, a pair of hearing aids could cost between $2,400 to $5,800 which may have insurance coverage limitations. Additionally, getting the hearing aids customized and fit may require an average of 2.5 visits to an audiologist. Due to inequity in access to audiologists, lower-income and rural residents are particularly affected. To resolve these issues, this research presents the development of a low-cost, over-the-counter (OTC) Hearing Aid with Live Fitting features that can be independently and conveniently customized according to the user's specific hearing requirements with a paired smartphone app.

In cases of severe to profound hearing loss, cochlear implants (CI) are considered to be important treatment devices in children and adults. One of the key challenges with these devices is poor speech perception performance issues in noisy environments. To address this issue, this research presents a novel hybrid FSP-CIS-HRP (Fine Structure Processing - Continuous Interleaved Stimulation - High Rate Pulse) based stimulation strategy. This was tested among 12 adult MED-EL cochlear implant users at the Medical College of Wisconsin. In both quiet and noisy environments, 7 out of 12 subjects showed improved speech perception performance.

Available for download on Sunday, May 24, 2026