Squeaking, humming, buzzing. The discomfort of tinnitus

One in three adults will sometimes hear a distinct tone in one ear for seconds at a time. The  ‘disco tinnitus’ phenomenon is also well known: if your ears have been exposed to a lot of noise for a while, you will hear a noise or whistling sound when in silence. It usually passes, but too much exposure to loud sounds can cause the noise or whistling tone to become permanent. In this case, you are suffering from tinnitus which is the subject of awareness raising this week during Tinnitus Week 2023.

A few years ago, the Bioelectronics group (Faculty of Electrical Engineering, Mathematics and Computer Science) joined an international project on tinnitus called Tinnitus House. Delta phoned TU Delft principal investigator Professor Wouter Serdijn to hear about the progress.

People suffering from tinnitus can fill in a survey on the website. What has that yielded?
“Almost 1,800 people have completed the survey. We ask them about the nature of their tinnitus, how long they have had it, whether they might have got it from professional activities. Some are musicians, others have been in the army. Still others got it after acoustic trauma in the form of blasting fireworks. We then use their profiles to try to map out what people have tried on their own and what has helped them. You can best compare it to Spotify’s recommendation system. You choose a particular song and Spotify comes up with recommendations based on other users’ profiles. Similarly, the Tinnitus House website gives recommendations of things you could try (to reduce the effects of tinnitus, Eds.).”

Can you give an example?
“Certain vitamins, for example. The scientific literature is not unequivocal on this, but there is a relationship between tinnitus and susceptibility to immune disorders. Certain vitamins have a positive influence on this. The survey suggests that people with a certain type of tinnitus might benefit from vitamin D3. Others benefit from creating certain conditions such as doing yoga or taking a shower – where you close your ears.”

What did you find out from the survey?
“It has pointed us towards solutions which would make sense for users. For instance, we are currently working on a small device that can stimulate the vagus nerve through pulses of electricity through the skin.”

Should I think of an electrical stimulation that reduces tinnitus?
“Yes, that’s right. We had one graduate student work on that and we will put a second one to work on it. We expect to test the effectiveness within a few months at BRAI3N clinic in Ghent, Belgium. The remedy is a combination of the electrical stimulation of a nerve and acoustic stimulation. It turns out, and there have been scientific studies on this, that if you give multimodal stimulation such as electric and acoustic signals at the same time, it increases the learning capacity of the brain. We want to teach the brain how to reconfigure itself. The brains of patients have organised themselves in a way that produces tinnitus, so we want to instruct them to start organising themselves differently. Not the whole brain, just the auditory cortex. Hence the combination of sound stimulation and electrical stimulation.”

What does that look like in practice?
“For now, this is still done with headphones and a sticker with electrodes. This allows us to test 20 patients in Ghent without any problem. But if you can reduce the equipment to an earpiece, there will be manufacturers of portable audio devices that will be very interested in it.”

• Do you also suffer from tinnitus? Join the study at Tinnitus House.