New thinking about Tinnitus

Harvard Medical School scientists close in on a mysterious cause of ringing in the ears.

Experts have long speculated about the most common tinnitus symptoms. Tinnitus is a ringing or roaring or hissing sound in the ears that does not come from an external source. Some believe tinnitus can be caused by hearing loss.

The brain becomes hyperactive and produces a phantom noise when there is less sound entering the ears. However, this theory has not solved the issue for people who have normal hearing tests and still experience tinnitus, so what causes it?

Mounting evidence

Harvard Medical School researchers are increasingly uncovering evidence that some people may have “hidden” hearing loss: a loss of nerve fibres in the ear that does not show up on conventional hearing tests.

The phenomenon was first identified in laboratory mice in 2009, and “from there, it wasn’t hard to say that the loss of those nerve fibres in people who had normal hearing tests might be related to tinnitus,” says tinnitus researcher Stéphane Maison, associate professor of otolaryngology – head and neck surgery at Harvard Medical School and Massachusetts Eye and Ear.

Maison and his colleagues conducted the largest and most detailed tinnitus study to date, which was published in Scientific Reports on November 30, 2023. They recruited nearly 300 people (aged 18 to 72 years) with normal hearing who had either chronic tinnitus or no tinnitus.

Researchers evaluated the responses of the auditory nerve and the activity in the brainstem of the participants. When compared to individuals without tinnitus, those suffering from chronic tinnitus showed a reduction in auditory nerve fibers and heightened brain activity. “This aligns with the concept that due to hearing impairment, the brain might ramp up its activity, which could explain why you hear a tone or sound that isn’t actually present,” Maison explains.

What this means for treatment

For individuals experiencing quantifiable hearing impairment, the use of hearing aids can sometimes lessen the experience of tinnitus. However, these devices are not suggested for those with normal hearing test outcomes, even if there’s a suspicion of concealed hearing loss, due to the lack of available tests beyond research settings to quantify it.

Nonetheless, the emerging research connecting concealed hearing loss and tinnitus provides a glimmer of hope for those suffering from tinnitus. “In cases of concealed hearing loss, only a segment of the auditory nerve has deteriorated. Another segment remains functional for years or even decades. Additionally, several studies have demonstrated the potential to regrow nerve fibres in animals,” Maison explains. “If we can successfully regenerate these fibres in humans, it could potentially restore lost information to the brain, thereby reducing its overactivity and the sensation of tinnitus.”

Until such a breakthrough occurs — and its timing and likelihood remain uncertain — we are limited in our approaches to addressing this issue.

What you can do

If you’re experiencing tinnitus despite normal hearing tests, it’s important to speak to your audiologist. In rare cases, tinnitus can be the result of a pinched or pinched auditory nerve, earwax build-up, or damage to a blood vessel. Treating underlying conditions can sometimes reduce or even eliminate tinnitus.

On the other hand, more often than not, the only way to live with tinnitus is to learn how to reduce or live with it.

The following tips can help you do just that.

• Distract your brain
• Use mind-body therapies
• Join an online support group
• Reduce stress
• Live a healthier lifestyle
• Consider trying bimodal stimulation

A lot of our patients tell us that they have tinnitus. For the past two years, Sean has been taking various courses to help manage his tinnitus and now he is offering a comprehensive tinnitus treatment program at Kilmarnock Hearing Care.

The program will include: Tinnitus Management, Cognitive Tinnitus Therapy, Sound Therapy & Auricular Acupuncture.

The sessions will be 60 minutes long and the first three sessions will be free of charge (taster sessions).