The UCL Ear Institute stands on Gray's Inn Road, one of the busiest
thoroughfares in London. Outside, the din of modern life is relentless -
revving motorcycles, idling lorries, honking taxis and the blaring of
sirens. Inside, however, director Professor David McAlpine has just led me
into what is possibly the quietest spot in our throbbing capital. We are in
his anechoic chamber, a windowless room four metres square that could double
as a set for Doctor Who. Angular wedges of thick grey foam jut from the
walls and ceiling. As I step inside, my feet wobble precariously upon a
suspended trampoline mesh because the same foam wedges, it turns out, are
affixed to the floor beneath us. Their purpose: to absorb all sound waves.
The chamber is, in effect, “dead space”. As the triple soundproofed door
closes behind us, my head feels instantly muffled. When the lights are
turned off, plunging us into pitch darkness, things get distinctly eerie.
“In here,” McAlpine jokes, “no one can hear you scream.”
What I can hear, I realise after a couple of minutes, is that rare thing...
nothing. Pure, unadulterated silence. What McAlpine hears, however, is a
high-pitched tone, slightly more pronounced in his left ear than his right.
That's because while I'm blessed with robust hearing, McAlpine is among
Britain's five million tinnitus sufferers.
Often caused by prolonged or sudden exposure to loud noises, tinnitus is most
commonly described as “ringing” in the ears. Symptoms can vary widely - from
a low hum to a pinging and hissing that drives the sufferer to distraction.
For 300,000 people with the condition, symptoms cause sleep deprivation and
extreme anxiety, preventing them from leading a normal life.
The fear among auditory experts is that we are heading for a “tinnitus
timebomb”. If you regularly spend several hours a week clubbing or going to
gigs, or if you listen to your MP3 player at full volume, you will have
almost certainly experienced some temporary tinnitus already. Prolonged
exposure to excessive decibels can put your hearing in danger of permanent
damage. And countless studies worldwide have now confirmed that an overload
of noise levels is resulting in increased hearing loss among young people.
According to some estimates, noise levels have increased tenfold in recent
years - in shops and restaurants, in schools and at work, on trains and
planes, on urban streets and in the countryside, the global hum is becoming
a global howl.
Of course, tinnitus is not a modern phenomenon. McAlpine reminds me that
Thomas Hardy's Jude the Obscure was often troubled by the “sound of fish
frying” in his ears. However it has, until very recently, been a clinical
enigma with various “trial and error” treatments on offer, but no cure.
Advances in brain scanning over the past five years, combined with major
pharmaceutical investment, are changing that. According to Vivienne Michael,
chief executive of Deafness Research UK: “There is finally hope that
tinnitus will not be a Cinderella area of medicine for much longer.”
McAlpine, an auditory neuroscientist and adviser to Deafness Research UK, is
regarded as one of the world leaders in tinnitus research. He uses the
anechoic chamber to provide rigorous test conditions for hearing and to
support his studies into the brain-processing mechanisms underlying
tinnitus.
For years, the big question that perplexed scientists was whether tinnitus was
a ringing in the ears, or in the brain. “Our thinking now is that it emerges
as you go from the ear to the central nervous system,” says McAlpine. “If
you have some hearing loss with the ear, the brain tries to compensate by
switching up its own amplifier. One theory is that when your brain turns up
the dial, it doesn't just turn up the signal for frequency channels, it
turns up the noise - so like with a shortwave radio, you hear more sound,
but you hear more hiss as well.”
McAlpine is the first to admit that his personal experience gives an added
impetus to his work. Now 40, he pinpoints his own condition to a single
night, spent in a noisy Irish bar in Sheffield ten years ago, at a friend's
engagement party. “It was low-ceilinged room with massively loud music - so
loud I couldn't hear myself speak. I was there two or three hours, and
remember cutting the evening short because of the noise. As I left, my ears
were ringing.” He recovered, but two weeks later, while carrying out audio
tests in a laboratory, he realised that he was having problems hearing
higher frequencies. Since then, he has had recurring bouts of “mildly
annoying” tinnitus, which worsens when he has to do any long-haul travel
because of aircraft noise and air pressure. He no longer frequents loud
bars, “and I don't know anyone in the auditory world who uses an iPod,
except in a very limited way.”
Personal music players must, by law, be manufactured with a maximum volume of
100 decibels (although worryingly, according to Vivienne Michael there are
adverts on the internet offering “unlocking” services so that they can be
played at higher levels). Prolonged exposure to anything over 80 dBA (the
decibel scale) will damage hearing. At clubs and rock concerts, noise levels
can reach well over 110 dBA. Even classical concerts can exceed 100 dBA. (If
you think the differences seem slight, you need first to remember that
decibels are measured on a logarithmic scale, so a small increment can
result in a large increase in perceived volume. For those who are not
mathematically minded, an increase or decrease of three dBA represents a
doubling or halve of intensity - the energy it contains. So, for example, 73
dBA is twice as intense as 70 dBA.)
“If you go to a club, you wouldn't allow someone to shine dangerous lasers in
your eyes. And yet people regularly expose their hearing to damaging noise
levels,” says McAlpline. “For many young and otherwise healthy people,
tinnitus will be the first sign that they are not, after all, invincible.”
Dr David Baguley, Head of Audiology at Addenbrooke's Hospital, Cambridge, and
adviser to the British Tinnitus Association, fears it is “imminently likely”
that the number of tinnitus sufferers will rise as MP3 use increases. On the
upside, however, he points to several breakthroughs that are bringing us
closer to discovering the cause of the condition.
In the past five years, researchers in America and also at the University of
Nottingham have, with the help of functional magnetic resonance imaging,
detected brain activity related to tinnitus. They've found it in the
auditory cortex and also the limbic system - the part of the brain that
governs anxiety and emotion. “This is hugely significant,” says Baguley.
“The suggestion is not that tinnitus is stress-induced, but that stress
could be a factor because in people who complain of the condition, the part
of the brain that produces fearful emotions is exceptionally active.”
Elsewhere, in Belgium and Germany, studies into repetitive magnetic
transcranial stimulation have shown promise for some sufferers. The
treatment involves holding a magnetic plate just above the ear where the
auditory cortex is. Electromagnetic pulses then alleviate symptoms by
disrupting, and possibly resetting faulty brain signals. Sessions last
between five and 30 minutes. The treatment is painless and does not require
anaesthesia. The downside is that it is highly specialised, and requires the
use of expensive equipment found only in major neurology centres.
Among the most potentially exciting developments, according to Baguley, are
those within the pharmaceutical industry. Within the past two years, it has
been established that injecting the anaesthetic lidocaine into the
bloodstream of someone with tinnitus will bring about a complete absence of
symptoms for five minutes. “It is actually a very dangerous thing to do,
because it has heart and breathing implications, but what it tells us is
that somewhere in the brain there is a lock that can be unpicked,” he
explains. At least three major pharmaceutical companies are now actively
researching a drug solution to tinnitus. “This is a huge step forward in
solving the last great mystery of the auditory system,” says Baguley. “Many
goals are now in sight in terms of deafness and balance but for too long,
tinnitus has remained a heart-sinker of a condition. I'm more and more
convinced now that a drug solution will be possible within our lifetime.”
Case study: The ringing never stops
Tom Wilkinson, 29, works in IT development and lives in Topsham, Devon. His
tinnitus was triggered by going to rock concerts while he was at university
in Birmingham.
“I would always have a buzzing in my ears for a day or two after seeing a
band. Then one day, the ringing didn't go away. I got used to it, but
tinnitus is exacerbated by anxiety, and during a stressful period a couple
of years after I graduated, I sought help. A sound generator under my pillow
helped me at nights, and I have invested in specialist earplugs, which I
wear if I go to the cinema or a gig now. Tinnitus is a unacknowledged danger
among young people because ear problems are associated with middle and old
age. I think it is vital that we increase awareness of the dangers.”
How to treat it
Three years ago, a study by the charity Deafness Research UK showed that
millions of tinnitus patients were being badly let down by the NHS. The
research found that many GPs were unsympathetic and unwilling to refer
sufferers to a specialist. More than 50 per cent of patients were being
told: “There is no cure. You'll have to live with it.”
Since then the Department of Heath has produced a “tinnitus patient pathway”.
Dr David Baguley, a member of the DoH committee, says: “The aim is that all
patients receive timely attention and the same standard of care.”
For those seeking treatment, options include:
Sound generators. Tinnitus can be more of a problem during quiet times, such
as before sleep, when there are no everyday sounds to mask symptoms. Sound
generators are available on the NHS. There are under-the-pillow machines and
also a behind-the-ear version.
Digital hearing aids. Conventional aids can aggravate tinnitus symptoms
because they block the ear with an ear mould. With a new design, the canal
is left open as the hearing aid is connected into the ear by a thin tube.
Cognitive behavioural therapy has been found to improve patients' quality of
life, even when the volume of noise from the tinnitus remains the same. It
works by helping to change people's attitudes and behaviour.
Tinnitus Retraining Therapy is a specific form of counselling combined with
sound therapy.
Some sound advice
A survey in 2006 showed that more than a third of all 16 to 34-year-olds
admitted listening to their MP3 player for more than an hour a day and 14
per cent listened for more than 28 hours as week. The Deafness Research
UK/Specsavers survey also showed that 54 per cent of people did not realise
that listening to loud music on an MP3 player in a nightclub or at a concert
could damage their hearing.
The World Health Organisation recommends the 60/60 rule: that you listen to
your personal music player for no longer than 60 minutes at a time and at no
more than 60 per cent of its volume.
Apple has produced an update that allows people to set the maximum volume on
their iPods. It also comes with a code, so parents can stop their children
from undoing it. For more information on the patch and installation help
visit:
http://docs.info.apple.com/
article.html?artnum=303414
Cinemas and clubs regularly reach volumes of more than 100 dBA. For every two
hours of exposure at such levels, your ears need 16 hours of rest to avoid
permanent damage.
As a rule of thumb, if you can't make yourself heard easily to someone
standing a metre away, the noise level is too high.
Dehydration exacerbates inner ear function. Make sure you drink plenty of
fluids if you are in a noisy environment.
Cheap, effective earplugs are unobstructive and can protect the ear from
higher volumes in clubs or at concerts without blocking out the sound of
music or conversation.
On a plane, noise cancellation headphones will enable you to enjoy listening
to music without raising the volume unnecessarily.
Sounds above 80 dBA can damage your hearing:
Nightclub: 80-110 dBA
Pneumatic drill: 110 dBA
Rock concert: 110-120 dBA
Plane taking off 100 metres away: 130 dBA
140 dBA is the threshold of pain for many people
Source: www.dontlosethemusic.com
Deafness Research UK has information and factsheets on tinnitus at
www.deafnessresearch.org.uk
British Tinnitus Association has helpline on 0800 0180527 or visit BTA at
www.tinnitus.org.uk
