Jeremy Turner, associate professor of psychology, was awarded a $300,000 grant that took effect in January from the Tinnitus Research Consortium to develop a human test system for tinnitus. Turner already has a patented system that can measure tinnitus (ringing in the ears) in rats and mice; now his goal is to develop a system for people.
“My colleague and I were testing a bunch of rats, and we came across this finding that suggested that we might be able to measure tinnitus. The way we do this is to play sound to an animal and then take it away and then play sound again,” Turner explained. “What we do is introduce a silent gap, and if you are a normal hearing person, or rat, or mouse or guinea pig, your brain recognizes the silent gap as a change and fires off a lot of electrical activity.
“So what happens is that in animals with tinnitus, and we think also in people, the brain responds as if it does not hear silence very well. There’s something in there (tinnitus) that makes it difficult for the brain to detect the silent gap. For decades tinnitus researchers have been largely focused on what people with tinnitus are hearing; the pitch, the pattern, how loud it is, how bothersome it is. Our focus has been to ask the opposite question, what are they not hearing – silence.”
The system that Turner helped create measures the brain’s activity during this process and has been successful in doing so in rats and mice – which hear in the same way humans do. Now the testing has moved on to people which Turner will spend his sabbatical this semester trying to perfect.
One group that is very interested in a successful system is the Unites States government. Turner explains that tinnitus is the most common disability complaint by veterans, and in 2011 the U.S. Department of Veterans Affairs spent $1.5 billion in disability claims and was projected to reach nearly $2 billion in 2012.
“Those are monthly checks that people get by saying they have tinnitus, but there’s no way to measure it. Troops are exposed to a lot of noise out in the field, and there’s no real way to protect their ears. You can’t muffle them very effectively because then they can’t hear what’s going on around them. Sometimes the tinnitus emerges right after loud noise insults, but we also know that lots of noise exposure early in life has been linked to tinnitus that can emerge years or even decades later.”
With the kind of noise exposure veterans can encounter, tinnitus is a normal side effect, but the government is certainly interested in putting that to the test instead of blindly writing checks without a proper measuring technique.