Everyone's Health

HYPERACUSIS ( PAINFUL NOISE )

The term is derived from Greek.  “Hyper” is a prefix signifying above, beyond, or excessive.  “Acusis” is sense of hearing.  Logically then, we would think of a person with hyperacusis as someone with extra-good hearing, but this is not the case.    What troubles people with hyperacusis most is not “super sensitivity” for soft sounds, but rather the increased loudness perception for average or slightly loud sounds.  In other words, sounds that most people find to be a comfortable volume could be uncomfortably loud to a person with hyperacusis.

What is hyperacusis?  Is it increased sensitivity to faint sounds?

 No, hyperacusis is not hypersensitive, or extra-good hearing.  Hyperacusis is reduced tolerance to sounds of moderate volume.  For the person with hyperacusis, moderate to loud sounds, which would be easily tolerated by other people, are bothersome, annoying, uncomfortable, or even painful.

What causes hyperacusis?

 The origin of hyperacusis is in the central auditory nervous system, rather than in the ear (the cochlea).  Certain everyday sounds of moderate loudness are perceived as too loud.  One way of describing this problem is to state that the central auditory system amplification for sound is excessively high.

If hyperacusis has a basis in the central auditory nervous system, is it associated with any other central nervous system disorders ?

 Yes.  There are a variety of neurologic conditions associated with hyperacusis, among them post-traumatic stress disorder, chronic fatigue syndrome, Tay-Sach's disease, some forms of epilepsy, Valium dependence, depression, and migraine headaches.  A disruption of the chemical neurotransmitter called serotonin in the brain is a common feature of each of these disorders.   In some way, this neurotransmitter influences a person's sensitivity or reaction to sensory stimuli.  The exact physiologic mechanism underlying hyperacusis, however, is not known at this time.

How does hyperacusis differ from loudness recruitment?

People with hyperacusis typically have normal hearing, whereas loudness recruitment is associated with sensory hearing loss.  A better term for loudness recruitment is “abnormal growth of loudness.”   People with hyperacusis also have an abnormal growth of loudness, but it is a very different pattern from that seen with the typical person with cochlear (inner ear) pathology.

How is a person with hyperacusis tested ?

 A comprehensive basic exam performed by an audiologist is essential for starters.  The test battery should included pure-tone and speech tests as well as tympanometry to rule out conductive and/or sensory hearing loss.  Acoustic reflexes are usually not tested because the loudness levels needed are intolerable for people with hyperacusis.

What kinds of sounds bother a person with hyperacusis?

Often everyday sounds such as vacuum cleaners, water running from a faucet, telephones ringing, a dog barking, or even laughter are the most common culprits.  Sounds that are very high-pitched seem to be particularly bothersome, such as signals emitted by televisions, security systems, or answering machines.  The terms “shrill” or “harsh” are often used in describing extremely annoying, or even painful, sounds.

These complaints sounds like “phonophobia.”  What is the difference between hyperacusis and phonophobia ?

Phonophobia and hyperacusis are sometimes used interchangeably, but there are differences. Hyperacusis can be thought of as an intolerance to most moderate and loud sounds, while phonophobia is a fear of certain sounds, even at relatively modest loudness levels.

Is there any connection between hyperacusis and tinnitus ?

Yes. Hyperacusis and tinnitus often co-exist.  In fact, a person's complaint of hyperacusis (without tinnitus) should be taken very seriously, in part because hyperacusis may be a precursor of tinnitus.

Is hyperacusis mostly an adult problem, or can children also have it ?

Adults may be more willing and able to express their concerns about hyperacusis, but the problem can certainly affect children as well.  Children may cover their ears with their hands or run out of the room if there is an annoying sound, rather than calmly describing their intolerance to the sound.

Is hyperacusis more common in certain pediatric audiology populations ?

 Yes.  The problem is more common in children with disorders such as:  central auditory processing disorders, learning disabilities, attention deficit disorder (ADD), head injury, a history of chronic middle ear infections with conductive hearing loss, autism, and autistic like behaviors.

Since people with hyperacusis are bothered by loud sounds, wouldn't hearing protection (ear plugs) be part of their treatment and management?

No, quite the contrary.  People with hyperacusis should be advised to avoid silence.  The person's natural tendency is to seek out quiet.  Some wear earplugs almost constantly to avoid as much exposure to sound as possible.  This strategy is, in fact, counterproductive, because it is likely to prompt the central nervous system to increase gain even further.  Hearing protection should be considered only when there is the likelihood of exposure to high-intensity sounds that could potentially cause noise-induced hearing loss or during extended periods of bothersome noise (e.g., riding in an airplane or a car).

How can a patient avoid being in quiet places sometimes ?

The person with hyperacusis should strive to always be around low-level and pleasant sound.   At home, or in a quiet workplace, he or she can play a radio at a low volume.  The use of environmental noise generators (available from many stores and mail-order companies) is also recommended, especially at night in the bedroom.  Finally, it is quite appropriate, and often very effective, to be fit with low-level noise generators (also called tinnitus maskers) by an audiologist.

Tell me more about these low-level noise generators.  Do they offer a “cure” for hyperacusis ?

There is no overnight cure or treatment for hyperacusis, or tinnitus for that matter.  However, constant stimulation over the course of months with very consistent, pleasant, low-levels of noise can help the brain readjust to everyday sounds.  Professional audiologic testing and counseling should always be completed before a person is fitted with noise generators.

This is a reprint for patient educational use. It is an excerpt from The Hearing Journal, pg 10; article by James W. Hall III, Ph.D.

Dr. Hall is a Professor of Hearing and Speech Sciences at Vanderbilt University.

Prior | Tell us what you think | Next

Add to Your Social Bookmarks: Del.icio.us Digg Furl Reddit Simpy Spurl Y! MyWeb - StumbleUpon