This Q&A with Dr. Julia Drouin, AuD, PhD, explores highlights from her related article, Leveraging interdisciplinary perspectives to optimize auditory training for cochlear implant users, to explore auditory training optimization for cochlear implant users.
What inspired you to research this topic?
As clinician-scientist, I have always been interested in research areas that bridge basic science with patient care. My early research examined the mechanisms that support adaptation to variation in speech input, which is something that all listeners encounter in everyday life. For example, consider the last time you had a conversation with someone who had an accent or dialectal difference; initially, you likely had to work a little harder to track what that individual was saying, but given enough exposure you’re able to comprehend the speech signal and follow the conversation without problem. A running theme in that line of research was that lexical context, or the word context in which you hear a sound, helps to drive the speech adaptation process.
While I was completing this research, I was in the clinic working with cochlear implant patients and observing tremendous variability in speech adaptation following implantation. Seeing the clinical need to improve patient outcomes drove my desire to merge basic research on speech learning with translational research to improve speech adaptation.
You take an interdisciplinary perspective to highlight the role of top-down lexical feedback on adaptation to atypical speech input – why is active auditory training important?
Active auditory training following cochlear implantation allows the reorganization of brain regions that are sensitive to spoken language. I think about auditory training as exercise for the brain; while receiving the cochlear implant is an important part of the process, learning to adapt to the newly transmitted acoustic signal takes time, effort and continuous practice.
Active auditory training integrates listening exercises from the lowest levels of sound processing (e.g., dissociating the difference between two different speech sounds) to higher levels of sound processing (e.g., putting together words to form a sentence). While many cochlear implant users adapt to their device passively, meaning without structured auditory training in place, it may be more time-consuming and effortful to learn to understand spoken language than engaging in auditory training immediately after implantation.
How can auditory training be optimized in the rehabilitation process?
Optimizing the rehabilitation process for individuals with cochlear implants is a primary focus of my research program and an area of active investigation across the field. The ultimate goal is to maximize patient success with a hearing device and maximize spoken language comprehension early in the rehabilitation process. Auditory training is one of many clinical tools to support the rehabilitation process. We hope that our continued research helps to integrate custom recommendations to support individual patient needs.
Based on your research, what’s the relationship between the role of aural rehab and neuroplasticity?
Neuroplasticity is the mechanism that supports our brain’s ability to change as we learn. While our brains are flexible and change in response to experience, research has shown that age drives this process differently. Consider the last time you tried to learn a new language in adulthood – for most adults, learning a new language can be challenging and slow, whereas children seemingly pick up a new language quickly and with less effort. While both children and adults can learn new skills, children show heightened brain plasticity relative to adults. This has important implications for monitoring how quickly/efficiently a listener adapts to their cochlear implant during the aural rehabilitation process.
For listeners who are adapting to devices like cochlear implants, there’s a significant learning period because the auditory signal transmitted through a cochlear implant is markedly different than the auditory signal available to a normal-hearing listener. Because of this, auditory training can improve the process of learning to map the auditory signal onto speech meaning. The brain reorganizes in response to improved spoken language processing. An important note is that there is individual variability in how much auditory training is needed to observe significant speech comprehension improvements and it may be related to neuroplasticity differences.
Any key takeaways that professionals should know?
The aural rehabilitation process is a critical component of cochlear implantation. Auditory training implemented early in the rehabilitation process can help to support spoken language adaptation. Both children and adults can be good candidates to participate in auditory training during the rehabilitation process. Apps like Cochlear™ CoPilot can be a great tool for supporting spoken language processing after implantation.
Read more about auditory perception and training for adults with cochlear implants and read the CoPilot Evidence Summary here.
About the author:
Dr. Julia Drouin is an assistant professor at California State University Fullerton in the department of Communication Sciences and Disorders and faculty affiliate at the Center for Hearing Research at the University of California Irvine. She is the principal investigator of the Auditory Language Learning (ALLears) Laboratory.
She earned an Au.D. and Ph.D. from the University of Connecticut in 2020, with interdisciplinary training in the neurobiology of language. She completed her clinical residency at the Yale Hearing and Balance Center. Her research program examines how listeners adapt to the acoustic signal of speech, with emphasis on how listeners with hearing loss adapt to devices like cochlear implants.