CHAPTER
SEVEN
Tinnitus and Hyperacusis
David
M. Baguley, Ph.D.
It is relatively
well established in the public mind
that being in the midst of intense sound
may lead to tinnitus (ringing), and
many high profile musicians are susceptible.
One example mentioned in an earlier
chapter is The Who’s guitarist
and songwriter Pete Townshend, who overused
headphones at massive intensity while
recording in the 1970s and has noise-induced
hearing loss and tinnitus as a consequence.
Hyperacusis (hypersensitivity of hearing)
is given less attention, but can be
a debilitating symptom associated with
noise exposure.
In this chapter, tinnitus
and hyperacusis are defined, and the
mechanisms that can cause them to be
troublesome as a consequence of noise
exposure are discussed. The problems
associated with these symptoms, such
as anxiety, sleep disturbance and irritability
are reviewed, and then hopes for recovery
and how this might be achieved through
therapy are considered. Finally, prospects
for future research are proposed.
Tinnitus has been
known since ancient times, with references
in the early medical texts found on
clay tablets in Ancient Babylon, and
in medical writings from Ancient Greece
and Rome. The word “tinnitus”
itself derives from the Latin verb tinnire
(to ring) though ringing is only one
of many manifestations of the symptom.
It’s worth repeating from Chapter
1 that it is pronounced TINN’-ih-tuhs
or tih-NEYE’-tuhs. A widely used
modern definition of tinnitus is, “The
conscious expression of a sound that
originates in an involuntary manner
in the head of its owner, or may appear
to him to do so” though even this
is not perfect as many people may experience
tinnitus that appears to originate outside
the head or even elsewhere in the body.
The experience of
tinnitus is common. About a third of
adults in western countries say they
have experienced short-lived spontaneous
tinnitus from time to time, and about
one in ten says that tinnitus is troublesome
for them. About one in twenty adults
has sought a medical opinion, and in
one in 200 people, tinnitus is severe
and has a significant negative impact
upon life. Interestingly, if children
are asked carefully and in appropriate
language about tinnitus, the figures
are similar to those in adults. This
equates to over 1.5 million Americans
having tinnitus that impact upon their
quality of life. Having hyperacusis
does not mean that you have supersensitive
hearing like Superman. Rather, it describes
a symptom where sound that is not especially
loud, and not bothersome to other people,
seems overwhelming and intense. A scientific
definition is, “abnormal lowered
tolerance to sound.” The word
hyperacusis entered the medical literature
in 1938, but the symptom was not given
wide attention until the last decade.
Some researchers have made the distinction
between hyperacusis and other sound
tolerance problems associated with fear
(phonophobia) or aversion to sound (misophonia).
A well established self-help resource
for hyperacusis called the Hyperacusis
Network (www.hyperacusis.net) likes
to use the phrase, “collapsed
sound tolerance” which carries
some emotional impact.
It is not a simple
matter to determine how many people
have hyperacusis. A Swedish study proposed
a figure of 8%, but many experts think
this is an overestimate, and the real
figure is about 2%. Tinnitus and hyperacusis
often occur together: nearly half the
people who complain of tinnitus have
hyperacusis, and over 80% of people
who complain about hyperacusis have
tinnitus.