Neuroscience may offer hope to millions robbed of silence by tinnitus
Chronic tinnitus affects millions of
Americans, and is the most widely reported disability among veterans.
New research reveals the roots of the disease lie deep within the brain,
and experimental therapies are providing hope for a cure.
An
MRI of the brain of a chronic tinnitus sufferer reveals regions that
are affected by the disease. Video still from PBS NewsHour
BY JENNY MARDER
National Science Foundation provided funding for this project
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 is 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 takes care of
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 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 trial, 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.”
