Imagine not being able to leave your house because the sound of the door as it bumps against the jamb hurts your ears... or giving up your job because you cannot tolerate the whirring of the fan in your computer. Imagine that you nearly faint from the squeal of bus brakes. This is how it is for people who have hyperacusis.
Hyperacusis is a confusing term because it literally means "better than average hearing," hardly an accurate description of a disruptive - even disabling - condition that may affect several million people in the U.S. alone. The term refers instead to a change in a person's auditory system that causes ordinary sounds or noises to seem unbearably loud. By creating significant anxiety and apprehension, hyperacusis can also contribute to a deterioration of general physical health and lead to negative changes in lifestyle. Associated conditions frequently include insomnia, depression and loss of sexual drive.
People who develop severe cases often go to great lengths to diminish the impact of environmental sounds, including moving to new homes, purchasing quieter vehicles or isolating themselves socially. One woman removed all the electrical appliances from her home, moving her refrigerator to a nearby garage, in order to escape having to hear the operation of each device. Although this may seem an extreme reaction, it is in reality a rational strategy for a person in her situation.
Most individuals with hyperacusis employ earplugs and earmuffs to avoid exposure to external noises, a more practical coping strategy. It has been shown, however, that utilizing ear protection can worsen the condition, causing affected people to use more and more, sometimes several pairs of earplugs at once, further exacerbating their situation.
Although clinicians have been aware of the condition for well over 30 years, the medical and audiological communities were slow to delve into its characteristics and causes. As recently as 1997, an Internet search with the keyword hyperacusis resulted in 11 references to sites containing information. Today, a similar search produces over 14,000 hits!
For some time, it was most often mentioned as a side effect of other primary diseases or serious medical conditions (e.g., aneurysm, head injury, etc.) but findings are gradually revealing that hyperacusis could be a primary condition. As a result, it is now the specific focus of several research projects.
Hyperacusis has been linked most often with tinnitus, phantom auditory perceptions that include ringing or chirping in the ears. In fact, it was the 1985 discovery by Dr's. Pawel Jastreboff, now at Emory University in Georgia, and Jonathan Hazell, The Tinnitus and Hyperacusis Centre in London, of a strong correlation between the two conditions that helped ignite the recent surge in scientific interest in reduced sound tolerance.
During their research in quest for new treatment protocols for tinnitus, Jastreboff and Hazell found that about half of their patients also experience hyperacusis.
The exact etiology is unknown but there are promising studies that point to the part of the auditory system that regulates instructions from the central nervous system. Every incoming signal is analyzed and responded to instantaneously by the central nervous system. For example, the tiny sensations of very soft sounds are amplified by exaggerated movements of the delicate hair cells in the cochlea. Very loud sounds are dampened or inhibited by actions of the middle ear muscles and bones.
It is theorized in the case of hyperacusis that the central nervous system does not respond properly to the incoming signal, miscuing the amplifying or dampening actions of the cochlea and middle ear. This creates a situation where an ordinary level of sound, conversational noise for example, is perceived as if it were as loud as a jet engine roar.
These problems in central auditory system function can occur following a head or neck head injuries and the emergence of these auditory disorders.
In all cases, diagnosis and evaluation of hyperacusis can be time consuming and the process is fraught with challenges directly tied to the secondary psychological conditions that nearly always accompany it. Among them is phonophobia, a fear of sound. Severely phonophobic people may believe that even very soft sounds will permanently damage their hearing. This causes tension and even panic in a variety of settings, including a hearing examination. Working with a coordinated care circle of medical providers, including psychiatrists, can be appropriate in these cases.
Once a diagnosis is made, treatment options do exist. Jastreboff and Hazell themselves developed a technique, Tinnitus Retraining Therapy (TRT), that helps many patients to show improved thresholds for sound tolerance over time.The application of broad band sound via bilateral ear-level devices stimulates the entire cochlea in a controllable way. According to a clinical study released by Jastreboff and Dr. Margaret Jastreboff in 2003, this method often produces dramatic results in about six months and over 80 percent of treated individuals may achieve a complete recovery.
Since it was introduced in the mid-1980s, TRT has become the primary treatment of choice for hyperacusis. Alternatively, pharmaceutical therapies are prescribed, including anti-depressants, anti-anxiety and anti-obsessive compulsive medications. Unfortunately, many of these medications induce undesirable side effects, such as lethargy and fatigue.
Thousands of people have been diagnosed with hyperacusis, received appropriate treatment, recovered and returned to a normal life. This good news needs to reach people suffering unnecessarily.
Medical professionals - from primary care physicians to neurotologists, audiologists and psychiatric specialists - must also be made aware of how to diagnose and treat hyperacusis. And finally, the insurance industry must be included so that treatment is eligible for coverage.
With access to information and a supportive team of professionals, people whose lives are now disrupted by hyperacusis are able to recover. Everyday sounds need no longer be something to fear.
Dr. Marsha Johnson, Audiologist
Oregon Tinnitus & Hyperacusis Treatment Clinic
Comments, questions? Contact Dr. Marsha Johnson.