U-M team develops device to treat tinnitus
A University research team has created a device to combat tinnitus, a condition that causes ringing in the ears, which affects 15 percent of Americans and is caused by nerve activity in the brain.
According to the Center for Disease Control, tinnitus leaves two million people unable to work and is the most common cause of service-connected disability among veterans. While the condition has no cure, the device helps improve the quality of life for those who suffer from it.
Tinnitus is often a result of nerve damage from things such as a loud concert or a gunshot, according to Medical School Prof. Susan Shore, who led the research team. Shore and her team identified a way in which touch and sound can relieve the occurrence of ringing.
“Combining the stimulation of the somatosens with the auditory systems … showed that a particular combination of sound and the somatosensory stimulation can actually depress the firing of these neurons,” Shore said.
The researchers identified the intervals of sound and orders of touch that caused the depression of the firing nerves. They took that information and used it to stimulate the same nerves on a guinea pig for 20 minutes per day for 25 days. The results showed a reduction in the firing of the cells, thus reducing the tinnitus in the animals.
“We use guinea pigs because they are a good model for auditory research because their … peripheral auditory system is similar to humans,” Shore said. “Also their brains are easy to access for recordings.”
After seeing its success in guinea pigs, scientists took the experiment to humans, creating a non-invasive way to stimulate human auditory nerves for 30 minutes per day. In the 20-person trial, each subject was given a box with wires attaching electrodes that connect to the face or neck and an earphone.
In order for the device to work, scientists must program it to fit the subject’s unique tinnitus patterns and pitch. Inaccuracy in the device could worsen the subject’s tinnitus.
The success of this trial provides insight into the science of the brain and auditory system.The hope is that this research can be used to help others with auditory disorders. The research team received funding in the fall from the National Institutes of Health for a larger 50-subject study. Following the larger trial, the team plans to commercialize the product, which it already has patented.
“This tells us a lot about how the circuitry in the brain changes after noise damage and tells us how the auditory system works in general, so that can end up helping other kinds of hearing disorders as well,” Shore said.
But according to a Gizmodo article about the device, it has its limitations. Following the end of the trial, much of the tinnitus returned in subjects. The study also only worked with those with a specific form of tinnitus, so this means that the device might not work for 20 percent to 40 percent of its sufferers.
“The subjects’ tinnitus largely returned a week after they stopped using the device, even for the two people who reported losing it completely,” according to the Gizmodo article.
Business sophomore Jordan Stanton often spends time around loud music as a student DJ at WCBN radio station and member of the Michigan Electronic Music Collective, and he fears the effects of tinnitus.
“I was basically told by a close friend with tinnitus who played the violin that I should be very careful about listening to loud music consistently,” Stanton said. “I recently decided to purchase some hearing-protecting earbuds to use during DJ sets and concerts to avoid tinnitus onset.”