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Neuroscience may offer hope to millions robbed of silence by tinnitus

BY Jenny Marder  November 6, 2013 at 11:28 AM EDT

An MRI of the brain of a chronic tinnitus sufferer reveals regions that are affected by the disease. Video still from PBS NewsHour

On Easter Sunday in 2008, the phantom noises in Robert De Mong’s head dropped in volume — for about 15 minutes. For the first time in months, he experienced relief, enough at least to remember what silence was like. And then they returned, fierce as ever.

It was six months earlier that the 66-year-old electrical engineer first awoke to a dissonant clamor in his head. There was a howling sound, a fingernails-on-a-chalkboard sound, “brain zaps” that hurt like a headache and a high frequency “tinkle” noise, like musicians hitting triangles in an orchestra.

Many have since disappeared, but two especially stubborn noises remain. One he describes as monkeys banging on cymbals. Another resembles frying eggs and the hissing of high voltage power lines. He hears those sounds every moment of every day.

De Mong was diagnosed in 2007 with tinnitus, a condition that causes a phantom ringing, buzzing or roaring in the ears, perceived as external noise.

When the sounds first appeared, they did so as if from a void, he said. No loud noise trauma had preceded the tinnitus, as it does for some sufferers — it was suddenly just there. And the noises haunted him, robbed him of sleep and fueled a deep depression. He lost interest in his favorite hobby: tinkering with his ‘78 Trans Am and his two Corvettes. He stopped going into work.

That month, De Mong visited an ear doctor, who told him he had high frequency hearing loss in both ears. Another doctor at the Stanford Ear, Nose and Throat clinic confirmed it, and suggested hearing aids as a possibility. They helped the hearing, but did nothing for the ringing.

Meanwhile, he scoured the internet for cures. He spent $700 on “miracle drugs” and vitamins marketed for tinnitus. He tried 10 sessions of acupuncture. But his depression and insomnia were getting worse. He had become suicidal.

“I just wanted to go into a cave and either get well or die,” he said.

So in November, at the urging of a therapist and fearful of his own behavior, he checked himself into the nearest emergency room.

“If I had a light switch, and I could have clicked that light switch and been dead, I would have done it,” he said. “I would have done it. But suicide is a complicated thing. I didn’t have a gun, I didn’t have the medicine to do it, I didn’t like heights. So how do you take yourself off the planet?”

When relief finally came for De Mong, it was not in the form of a tinnitus specialist or an ear doctor, but a psychiatrist. He was referred to the doctor after several hours of hospital observation. While he insisted his problem was the ringing, she diagnosed him as depressed and prescribed sleeping pills and an antidepressant, Effexor. Finally, he said, he began to sleep. And slowly, the depression — and along with it, the severity of his tinnitus — began to improve. It’s a message he wants others suffering from the condition to know.

“If you’ve got ringing in the ears, the first thing you should do is see a psychiatrist,” he said. “She saved my life.”

Watch PBS NewsHour science correspondent Miles O’Brien report on the latest tinnitus research and his own experience battling the condition.

Inside the Tinnitus Brain

De Mong is not alone. Of the 50 million Americans who experience tinnitus at some point in their lives and the 16 million who are bothered enough to seek help, 2 million have it to a degree so severe that it’s debilitating, according to the American Tinnitus Association. It is the leading disability among veterans, outranking even post traumatic stress disorder, according to disability claims from the Veterans Administration’s 2012 fiscal year report. There is no cure for tinnitus, and no medication known to effectively treat it.

While tinnitus originates with hearing loss, the problem is actually rooted deep in the brain and caused, researchers believe, by a complex interplay of brain signals gone wrong.

It begins with damage to tiny vibrating receptors called hair cells in the snail-shaped cochlea of the inner ear. That injury results in two things: hearing loss — gaps in certain frequency ranges of hearing — but also a remapping in the auditory cortex of the brain, where signals received from the inner ear are processed.

“That’s where the first thing goes wrong,” said Josef Rauschecker, a professor of neuroscience at the Georgetown University Medical Center, who has been researching tinnitus for nearly a decade.

The brain tries to fill in the gaps, and it does so by creating phantom sounds. On MRI scans, scientists see evidence of this as hyperactivity: an excess firing of neurons in the brain’s auditory cortex.

It’s not unlike the phantom pain one gets after losing a limb. It’s common for amputees to feel itching or aching in an arm or leg after it’s gone. This is because even after the amputation, neurons in the brain continue to fire, signaling the presence of that limb. A similar thing is happening in the auditory system. Even though the receptors are damaged, the brain continues to fire, but excessively so.

These facts are undisputed. But Rauschecker’s team takes it a step farther. He believes that something else is happening in the ventral medial prefrontal cortex, a region in the brain’s executive center. That part of the brain tries to stifle the phantom sounds, and it does so using a “noise-cancellation system,” a sort of volume control that cranks down their intensity. It doesn’t just suppress tinnitus sounds, he says. It also keeps you from hearing noises inside of your body at full throttle — your heartbeat, for example, and your breathing.

“This is something that’s become very interesting in the last several years,” Rauschecker said. “People realize that perception is not just a bottom-up process, where something comes into your sensory organs — your eyes or your ears — and then goes up to the brain and that’s it. There is also something coming down from the higher centers that can then control those sensory signals. And that’s very handy in everyday situations. You don’t want to hear everything.”

Rauschecker is a soft-spoken man with rosy cheeks and an Austrian accent who smiles with his whole face. Driving his research is his own struggle with tinnitus. It started about a decade ago in his left ear as a high-frequency hiss, coming and going at first, like an unwelcome houseguest.  But as time passed, it began to stick around longer and longer. He describes it as uncomfortable, sometimes very loud, but, he’s quick to point out, not debilitating. Still, his experience has allowed him to make certain observations. When he is stressed or sleep deprived, the tinnitus gets worse, for example. Relaxation helps. So do weekends.

Among three independent cohorts of tinnitus patients, Rauschecker and his team have found volume loss — a loss of neurons, he believes, and possibly glial cells — in the ventral medial prefrontal cortex, home to this suppression system. What’s more, the degree of volume loss correlates with the loudness of the tinnitus. What they’re seeing when they look at the scans, he believes, is the suppression system broken. What they’re seeing is chronic tinnitus.

“It’s really a robust finding,” he said. “We’re very confident about this.”

But here’s the puzzle: Why do some people with hearing loss live happily, even blissfully unaware of it, while others hear dental drills and hissing power lines? Why do only 30 percent of hearing loss cases progress to chronic tinnitus?

“This is where the field has to shift now,” Rauschecker said, “Toward asking exactly that question.”

Among his future goals is to better understand what causes this system to become compromised. Rauschecker believes that many understand tinnitus backwards, assuming a causal relationship between the tinnitus and the behavioral problems so common among patients with the condition, as if tinnitus was the cause, and the depression, anxiety and insomnia, the effect. When in fact, he says, they’re all part of the same underlying disorder. And in some cases, the depression is what’s making the tinnitus worse, not the other way around.

“We’re saying, Well, there’s an underlying disorder maybe having to do with serotonin

depletion or whatever that causes the insomnia and the tinnitus,” he said. “So they are both effects of the same affliction, in a way. You can’t really say one is the consequence of the other. They’re mutually dependent.”

Targeting the neurotransmitters involved could open up new avenues for treatment, he said. For example, he’s hoping to conduct a rigorous study on SSRI antidepressants, drugs that block the reuptake of serotonin in the brain, as a possible treatment for turning down the volume on the tinnitus.

 

Another Approach

In San Francisco, a separate research team has found another part of the brain actively involved in tinnitus: the basal ganglia. Using state-of-the-art MRI scanners to peer deep inside the brains of tinnitus patients, Cheung and his team have managed to pinpoint an important source of the phantom noise. The basal ganglia plays a role in many involuntary processes in the human body, from establishing balance, to repeating often-rehearsed motions, to maintaining a sense of passing time. Cheung believes this part of the brain contains a sort of gating system. When the gate is closed, the tinnitus is held back — and on mute. When it’s opened, the noise floods through. Cheung and his team believe if they can go in and manipulate that part of the brain, they just might be able to muffle the noise — and provide some real relief.

The basal ganglia

The basal ganglia rests just below the cerebellum and above the brain stem in the human brain. The structure may help regulate the ringing in the ears known as tinnitus. Video still from PBS NewsHour

And they have good reason to believe that. In a pilot study on Parkinson’s patients with tinnitus, Cheung’s team found that by using a probe to send pulses of electricity into the brain, they could turn the volume up or down on the patients’ tinnitus, at least temporarily.

 “It is an exciting finding, and it’s led to other studies with imaging and a phase one trial of deep brain stimulation for tinnitus,” Cheung said, adding that he’s confident that the field is advancing.

“There’s not yet a cure,” he said. “We will find a cure.”

 

Seeking Help in Unlikely Places

For now, with that cure still looming in the distance, patients seeking treatment are often met with frustration and dead ends.

“The ENT’s say, ‘well it’s not in the ear, so we can’t help you,’” Rauschecker said. “And the neurologists usually aren’t very interested in this either, because they don’t understand it, and tinnitus is a small domain.”

There’s no lack of homeopathic drugs, vitamins and herbs online, boasting a quick fix for tinnitus. James Henry, who works for the National Center for Rehabilitative Auditory Research at the VA Medical Center in Portland, said to beware of these online “remedies.”

“My advice would be to be skeptical of anything on the internet,” Henry said. “Don’t be taken in on unproven methods. Don’t spend money on things that aren’t proven to work.”

But sufferers are not without options. Henry has been researching treatment methods for tinnitus for 20 years. These include methods to use sound in various ways as therapy, counseling and behavioral training. While their success varies according to the patient, the methods can be helpful for many patients.

A combination of counseling, sound therapy and coping techniques that help a sufferer learn to manage reactions to the tinnitus can be very effective, he said. His team has developed a five-step program that includes audiology testing and evaluations, the use of external sounds to manage tinnitus, and cognitive behavioral therapy, which teaches coping techniques. The stepped-care program provides services only to the level required by each patient.

“These can include deep breathing and relaxation exercises — anything to calm the patient down,” he said. “If patients are stressed, they learn to sit down, get comfortable, use deep breathing, close their eyes and imagine something pleasant.  A psychologist also teaches them distraction techniques.”  

Cognitive behavioral therapy, in particular, has proven helpful for many severe tinnitus sufferers, he said.

Jennifer Gans is a clinical psychologist and researcher who specializes in this kind of therapy for tinnitus. She calls it mindfulness. Sixteen years ago, Gans was hit by a truck and sent into a five-day coma. That accident, and the painful recovery that followed, made her especially attuned to managing pain. She has since developed a mindfulness program for tinnitus, modeled after techniques used for chronic pain. Key to the program is accepting the tinnitus, she said. Focusing on it, rather than pushing it away and turning inward to harness existing powers of healing.

“There’s a Buddhist saying: pain in life is inevitable, but suffering is optional,” she said. “I’m working with the people on their suffering about their tinnitus, helping them to change their relationship to the tinnitus or whatever pain in life comes their way.”

She calls it “moving into” the tinnitus, and compares it to driving on ice.

“If you turn away from the skid as we’re not supposed to, the car spins out of control,” she explains. “But if you move into the skid, there’s this moment of skidding with it where all of a sudden, you reestablish balance, eventually.  And so that is essentially what I see as what’s helpful for tinnitus — it’s not pulling away from it.”  

De Mong, who took one of Gans’s eight-week tinnitus workshops, recalls one of the final exercises, a method that Gans called “breathing into the tinnitus.” The idea of doing such a thing terrified him, he recalls.

“I argued with her. I didn’t want to do it,” he said. “I thought, ‘it’s going to be too painful.’ But I did it. And I found that it softens the tinnitus. It softens it a lot. It doesn’t make it go away. But it softens my reaction to it. It’s what I still do today.”  

Even with the help of mindfulness and medication, De Mong faces a constant struggle with both the tinnitus and the depression always looming in his brain, ready to manifest as more darkness, louder sounds. Doing interviews for this story made his tinnitus worse and his depression more prominent.  

About five years ago, he wrote a personal account of his experience with tinnitus, documenting all of his doctors appointments, his medication and the treatments that both did and didn’t help.

“Quiet times used to be one of my favorite things,” he wrote. “Now, silence is just torture… It hurts. When I’m in a quiet room I just want to run out of the room as fast as I can.”

The act of writing about his tinnitus made it so loud “that it would feel like a dentist was drilling into my brain with his high speed drill,” he wrote. “This was the most painful document that I have ever written,” it ends. “To have to think about how tinnitus has changed my life is just brutal.”

But when it gets worse, he sees his psychiatrist or revisits the coping methods he learned from Gans and her mindfulness program.

“In the program, we did yoga, we did mindful living, we did breathing exercises and we did relaxation techniques,” he said. “What I do today from that program is breathing exercises and mindful living. To be mindful that I’m talking to you, mindful that I’m in a comfortable room, mindful that I’m not hungry. That I’m alive.”  

In May, Gans ran an introduction to her eight-week workshop with a roomful of veterans. She asked everyone to share their experience with their tinnitus. Tyler Brown, an army veteran, listed the loud noises he was exposed to during his three deployments in Iraq: fighter jets, machine guns, explosives. His tinnitus makes him more sensitive to certain sounds. For example, he avoids being around dogs or small children.

“It’s a weird thing,” Brown said. “Sometimes the tinnitus will just be there passing in the background, and it’s just annoying, it hurts in my ears. The other time I get it, it reminds me of setting a demo charge on a door then blowing it up.

At the workshop, Gans directed the veterans to close their eyes and focus on their breathing. She had them hold a raisin in their mouths and think about the flavor, the texture and the taste. That’s mindfulness, she said. “Being present and being aware that you’re present.”  

She ended the workshop with a story about wild monkeys in ancient India. She described a coconut with a hole carved out and a banana inside. The coconut was nailed to the base of a tree, and used as a trap, she explained.

“Now, this hole in the coconut was a special hole,” she said. “Just large enough for the monkey’s paws to go in, but too small for a monkey’s fist to pull out.”

Again and again, she said, monkeys run to the trap, stick their hand in the coconut, make a fist around the banana, and get stuck — trapped.

“All the monkey needed to do in order to be free was just to let go, but the monkey doesn’t always think to do that,” she said. “Now I’m not calling us monkeys, but maybe think about how you might be holding onto something, when all you need to do is just let go to have your freedom.”

“Maybe we’re like this around our tinnitus,” she continued. “Maybe we can practice just letting go and see what happens. Holding things a little bit more gently.”