Grant Searchfield: the buzz over tuning out tinnitus

When Professor Grant Searchfield put out a media release last August about some published research, he didn’t think he’d have to take a crash course in Spanish as a result.

Grant is Head of Audiology in the Faculty of Medical and Health Sciences, and the research paper, about a prototype therapy for dealing with tinnitus, was published in Frontiers in Neurology. Nine months on, the paper was still in the top one percent of that journal’s articles viewed online.

“Breakthrough in search for tinnitus cure” went, as they say, gangbusters. It outlined the success of a trial of a prototype and asked people interested in taking part in further trials to email Grant.
By February, he had received around 2,000 emails from people interested in the trial.

“We were surprised. We didn’t expect the global reach we got. We didn’t have a plan in place to deal with it, which was an oversight,” says Grant.

“When we put out media releases, we’re looking for a bit of publicity and to promote our research locally. I thought we’d get a few emails from the scientific community.”

Hola! Then Grant started receiving emails from Spain. “The emails in Spanish started arriving fairly early, because it had been published in a Spanish-speaking newsletter or journal.

“That went on for four months. As soon as we started getting hundreds of emails, it was clear this was something I needed help to deal with.”

Grant’s response?

“Forward them to Phil,” he jokes.

Phil is Dr Phil Sanders, a postdoctoral audiology research fellow who has been working with Grant on their digital polytherapeutic treatment for tinnitus, a multi-pronged therapy, which is what the research paper was about.

Grant updated the original online release that had asked people to email him, to instead ask them to register their interest on the TrueSilence Therapeutics website, the UniServices spinout company boosting the development of the tinnitus treatment.

So what was everyone so excited about?

After 20 years searching for a cure for the annoying aural affliction that’s essentially a false perception of sound, Grant and Phil’s study randomised 61 patients to one of two treatments, the prototype of their new ‘digital polytherapeutic’, or a popular self-help app producing white noise and nature sounds. On average, the group using the polytherapeutic treatment (31 people) showed clinically significant improvements at 12 weeks, while the other group (30 people) did not.

“Most therapies use either counselling, or sound therapy or hearing aids,” says Grant.

“What we do differently is personalise the care for each individual by looking at their particular needs, the problems they’re experiencing and the nature of their tinnitus. We then prescribe customised options within our software. There’s counselling, passive sound therapy (exposure to different sounds), and ways to retrain the brain, which include games.”

Some people can tune out from their tinnitus (a high-pitched ringing), while others can’t, and it seriously affects their lives.

“The games reward people for not listening to the tinnitus. So we’re rewiring the brain by providing stimulation that people need to focus on, instead of the tinnitus.”

The treatment is more than just an app – there’s clinician software, and hardware including headphones and even Bluetooth pillow speakers through which to stream the different therapies at night. Sounds people might choose include surf, a babbling brook, or wind in the trees. After the Auckland floods, there are likely to be fewer takers for the sound of rain.

Grant says the audiology researchers are working closely with clinicians because tinnitus can be associated with a medical complaint. The causes are complex – it can be caused by noise, the nervous system, or damage to the ear.

“Going through a clinician is the best approach because we see this as a health problem, rather than a lifestyle problem. And we’re enabling the clinician to be able to provide our therapy.”

TrueSilence Therapeutics is incorporated in the United States with funding from overseas entrepreneurs involved in the health tech sector. But local funding has helped propel this promising tinnitus treatment to where it is today.

“One of our strongest supporters for many years has been the Auckland Medical Research Foundation,” says Grant.

With funding from others, including the MedTech Accelerator Fund and the University of Auckland’s UniServices, the goal is to develop the treatment further, including using AI.

“Eventually, we will be able to tune to an individual’s needs based on artificial intelligence. If individuals are happy for their progress to be captured, that will create a large pool of data. Eventually, the therapy will become smarter.

“We also have funding to develop a headset for our EEGs, done as part of the patient analysis, so people don’t have wires all over their head, just a headphone to capture the information.”

Ultimately the plan is also to be able to use data extracted from smart watches or smart earphones or ‘hearables’ that have similar kinds of sensors.

“Then we can tailor the therapy based on the smart-watch readings that show whether you’re relaxed, stressed, have exercised or not had much sleep, for example.”

Tiredness and stress have been shown to be contributing factors to tinnitus in sufferers.

“The thing we commonly find is when people are tired, or there’s been a stressful event such as the loss of a loved one, it often leads to a spike. While for some it may subside, for others it will become a focus and it will be difficult for them to distract themselves from it.

“We also know that the worst cases of tinnitus are associated with post-traumatic stress disorder. Tinnitus is the number one medical injury complaint for Veterans Affairs in the US; number two is hearing loss.”

With soldiers, there can be injury to the ear, probably from a loud blast, and there may be a head injury causing concussion.

“Both of those are related to the onset of tinnitus. But they may also have experienced a profound psychological impact … the death of a friend or another horrific event.

“The perfect recipe for severe tinnitus is a combination of ear injury and some kind of psychological upset.”

Grant has attracted people with different skill sets to the TrueSilence project, such as research fellow Amit Barde who has moved over to Audiology from the Auckland Bioengineering Institute (ABI). Amit’s expertise includes sound design, spatial audio reproduction and AR/VR wearable devices. There have also been a number of other post-doctoral researchers involved, including Zohreh Doborjeh whose expertise is AI and who came to the University from AUT.

“For the engineering, we’ve been working with ABI; for some of the algorithm work, we’re working with AUT. It’s a really exciting environment.”

The goal is to run further trials and, ultimately, to gain FDA approval and have access to commercial markets, such as North America. It’s estimated there are around 60 million there with tinnitus.

“We’re working with New Zealand audiologists who provide expert input on the clinical pathway,” says Grant. “We test and refine here, with input from the US to make sure we don’t miss anything in the cultural economic translation.”

Clinicians, including GPs, will be upskilled in the TrueSilence treatment.

“Not all audiologists or clinicians are comfortable with providing tinnitus care. This tool makes it easier for them and takes some of the load off their practice.”

Grant and TrueSilence are also assessing the requirements needed to get approval from the US Food and Drug Administration (FDA) for their novel treatment.

“We believe what we’ve done so far meets FDA requirements. We monitor things like how the headphones work for people with hearing loss so as not to cause damage, how the software interacts, the useability, the sound levels.”

He concedes that to some extent the success of TrueSilence may be limited by the user, such as whether they are open-minded about technology. But Grant is confident that for the next step in development, they will find a software company that has experience in designing technology for seniors.

“When technology is done properly, intuitively, older people are very good at using it.”

As people age, the incidence of tinnitus increases. In New Zealand, the self-reported prevalence is highest in over 65s, at around 13 percent. Under tens is around one to two percent. It is also slightly more common in males than females, a gender bias that may reflect ‘traditional work’ roles in industry.

But situations can play a part too. Grant says in the absence of sound and normal auditory activity, the brain goes looking for it. A New York study published in 1953 tested a group of college students with normal hearing.

“Researchers put them in a sound-proof room, gave them a piece of paper and left them there for some time. They asked them to write down all the sounds they heard. Around 90 percent wrote that they heard crickets, whistling, humming or buzzing. These are the sorts of sounds people hear as tinnitus. As soon as they came out of that silent environment, the sounds disappeared.”

And all ages can get tinnitus.

“For young children, who are limited by being old enough to describe it, it will generally be related to a temporary ear infection as opposed to permanent damage to the inner ear.

But there’s a new threat. “Long-term exposure to music at high levels may well mean we’ll see a bit of an increase in a younger group.”

Grant says it’s important to note that not everybody with tinnitus will suffer from it.

“It’s really important to understand that. Some people have tinnitus, but develop ways of dealing with it, so for them it’s not a problem.”

He says that has led to a new definition.

“We’re beginning to hear more about ‘tinnitus disorder’, when tinnitus definitely has an impact. It’s not universally agreed upon though – when do you suddenly have tinnitus disorder? It’s not a switch, it’s more a continuum. But some people certainly suffer.”

As was indicated by those 2,000 emails. How did he get on with those?

“We answered them all. I’m happy to spend a moment pointing people in the right direction or updating them on TrueSilence’s progress. It’s not a big deal for me to help people like that, so I’m still fine to be contacted.”

Gracias, Grant.

Story by Denise Montgomery