Bruna Mussoi, Au.D., Ph.D.
Bruna Mussoi, Au.D., Ph.D.
Meet the Researcher
Mussoi received both her Au.D. and Ph.D. from the University of Iowa. She is currently an associate professor at The University of Tennessee Health Science Center. Her 2025 Emerging Research Grant is generously funded by Mike Miles.
Cochlear implants provide several benefits to older adults, though the amount of benefit varies across individuals. The greatest improvements in speech understanding abilities usually happen within the first six months after implantation. It is generally accepted that these gains in performance are a result of neural changes in the auditory system, but while there is strong evidence of neural changes following cochlear implantation in children, there is limited evidence in adults with hearing loss in both ears.
This study will examine how neural responses change as a function of the amount of cochlear implant use when compared with long-term hearing aid use. Our results will allow us to objectively quantify individual benefit from cochlear implant use in order to provide important information that can be used in counseling cochlear implant users, including among older adults.
The topic is something that I have been curious about for a while. I am amazed by how much older adults can benefit from cochlear implants, though there is a wide range of speech recognition abilities in this population (similarly to adults generally). It seemed clear that there should be neuroplastic changes to support these gains. Also, recent studies have shown that listeners who wear cochlear implants for a greater number of hours each day derive greater benefit. So, we will evaluate cortical auditory neuroplastic changes both as a function of time post- implantation and as a function of device use, and their contributions to speech perception outcomes.
Since my early clinical experience as an audiologist in Brazil, I have always enjoyed working with older adults. However, I found it puzzling that older adults have greater difficulty with speech perception, even without significant hearing loss. During my doctoral studies, I gained experience in working with cochlear implants and the substantial benefits they can provide. These experiences motivated me to examine the neural mechanisms underlying speech perception abilities in older adults.
When I was a child, I wanted to be a writer. I even wrote a poetry “book” and gave it to my grandmother, who was a language arts teacher. Back then, I never imagined that as a researcher I would merge my love for reading and writing with my interest in audiology. Others may be surprised to know that I also learned to speak five languages (Portuguese, English, Spanish, Italian, and Swedish). I enjoy getting to know different people and cultures, expanding my worldview.
In the future, I see myself expanding my lab and making meaningful contributions to the clinical care of the growing population of older adults. I also see myself continuing to work with and mentor students, as I enjoy the unique opportunity to help shape the next generation of clinicians and researchers.
Bruna Mussoi, Au.D., Ph.D., is generously funded by Mike Miles. We sincerely thank him for his support of hearing and balance science in the area of cochlear implant research.
The Research
The University of Tennessee Health Science Center
Auditory neuroplasticity following experience with cochlear implants
Cochlear implants provide several benefits to older adults, though the amount of benefit varies across people. The greatest improvements in speech understanding abilities usually happen within the first 6 months after implantation. It is generally accepted that these gains in performance are a result of neural changes in the auditory system, but while there is strong evidence of neural changes following cochlear implantation in children, there is limited evidence in adults with hearing loss in both ears. This study will examine how neural responses change as a function of the amount of cochlear implant use, when compared to longstanding hearing aid use. Listeners who are candidates for a cochlear implant (who either decide to pursue implantation or to keep wearing hearing aids) will be tested at several time points, from pre-implantation and up to 6 months after implantation. The results of this project will improve our understanding of the impact of cochlear implant use on neural responses in older adults, and their relationship with the ability to understand speech.
Long-term goal: The long-term goal is to better understand the mechanisms involved in differences in speech perception in older adults with cochlear implants. These studies will inform clinical practice, allowing us to objectively quantify individual benefit from cochlear implant use, and providing important information that can be used in counseling cochlear implant users. Lastly, as the population of older adults increases and as public health efforts focus on increasing access to cochlear implants, these findings are also expected to support advocacy for implantation in older adults.