Feb 2019 Nebraska Today
When Michelle Hughes arrived at the University of Nebraska-Lincoln in August, she brought with her a mission to improve programming for cochlear implants. Hughes, associate professor of special education and communication disorders, now has her Cochlear Implant Research Laboratory up and running at the Barkley Memorial Centre. She’s focused on better serving cochlear implant patients of all ages in the state and beyond.
First up: understanding how well neural measures in cochlear implant users predict what they can actually hear. Hughes hopes that refining this relationship will allow audiologists to better program cochlear implant processors, particularly in young children or people with developmental disabilities who may not be able to communicate what they are hearing.
While Hughes’ team analyses data from the initial studies, it is also investigating how changing the type of auditory stimulus might reveal more about nerve survival in cochlear implant patients. “Right now, we don’t have a way to know if Person A or Person B has better or worse nerve survival than the other person, and how well that is going to relate to how they do with the implant,” Hughes said. “Basically, what we know is that the longer a person is deaf, the auditory nerve fibres start to die off. But there are also certain causes of deafness that can cause more damage than others.”
Hughes is also exploring the feasibility of providing cochlear implant services through distance technology or videoconferencing. So far, she has determined that programming children’s cochlear implants works as well remotely as in face-to-face settings. Now, Hughes is looking for a way to also measure speech perception through these telepractice technologies. “When cochlear implant patients have their processors programmed, there are outcomes that need to be measured to determine how well they are doing with the implant,” she said. “How well can they understand speech with the implant? We (measure) that by administering a speech perception test. It’s a recorded list of words or sentences, and the person has to listen to it and repeat back what they hear. Then they get scored on what percentage they get correct.”
Tracking the speech perception over time allows audiologists to notice when those scores begin to decline, Hughes said. This, in turn, helps the audiologist determine what might be causing the loss of speech perception – whether it’s an issue with the device or processor or a cognitive problem. The challenge with administering speech perception tests through telepractice, she said, lies in creating an environment similar to an audiologist’s office.
“Typically the testing is done in a sound booth, because it has to be quiet and you have to listen to the speech coming out of the speaker,” Hughes said. “Let’s say your patient is in rural Nebraska, and there isn’t a sound booth there. We are looking at alternatives, specifically … using a direct audio input into the processor so it bypasses the microphone. “So the project is exploring what are some alternatives to be able to do speech perception testing. And if you use those alternatives, do you get the same result as you do in the typical clinical situation when they come into the clinic and you test them face-to-face?”
True to its all-ages mission, the lab is also examining how best to deliver aural rehabilitation for adults. The goal is similar: determine whether a group that receives therapy via telepractice shows the same outcomes as a group receiving face-to-face therapy. Though she said there will be challenges to implementing the telepractice approach, Hughes hopes her findings will pave the way to its broader use.
After wrapping her current studies, Hughes will set her sights on developing a speech perception test that better represents real-life communication challenges. “We are using typical clinical tests for our research right now, and those tests don’t represent typical challenges that people with hearing loss or cochlear implants face in daily life,” she said. “The testing is usually done in a sound-treated booth, but people don’t live and work in sound-treated booths.”