The prefix “hyper” comes from the Greek word meaning “above” or “over.” Its counterpart, “acusis,” is the Greek root for hearing. Consequently, hyperacusis is a medical condition involving hearing that portrays sounds above what would be considered an average volume. You may suffer from hyperacusis if sounds are loud, often unbearably, painfully loud.
Unfortunately, hyperacusis is a common ailment. Approximately 1 in every 50,000 individuals suffers from hyperacusis. Within children and adolescents, the reported incidence is between 3% to 17%; the percentage is around 8% to 15.2% in adults. Because of the wide range of symptoms and differing criteria in medical literature, it isn’t easy to assess actual numbers accurately.
A perception-based model
There appear to be distinct criteria governing how an individual perceives hyperacusis, resulting in different labels to categorise these perceptions. Although there is some overlap, experts organize hyperacusis into the following subgroups:
Loudness hyperacusis
The most common form, loudness hyperacusis, is perceiving sound at a higher decibel than measured. It may vary in intensity between ears and only occur with certain frequencies at specific volumes. Even though the volume is not as loud as the victim experiences, any accompanying pain is real.
Noxacuses (pain hyperacusis)
When enhanced sound perception occurs with a prevalence of pain, it is called Noxacuses. Patients report ear, face, or even teeth pain, suggesting a neurologic component.
The standard description of this pain is similar to how others have described neuropathic pain. For example, patients often describe the pain as an interpretation of burning, stabbing, or identical to that accompanying a broken tooth.
Panic hyperacusis
Crying, anxiety, or panic attacks may be a part of an individual’s hyperacusis syndrome. This reaction is above and beyond typical stress and depression that may result from chronic or episodic symptoms. In addition, this exaggerated emotional response is noticeably out of character and may present even after the episode has passed.
Neurologic hyperacusis
In severe cases, the sudden onset of a hyperacusis episode can cause incoordination and produce a seizure. It is rare. However, it happens often enough that it needs to be the topic of discussion for those experiencing this ailment.
Who gets hyperacusis and what causes it?
The exact cause of the condition has yet to be identified, although science does know that specific syndromes and disorders are more likely to experience hyperacusis. Some theories suggest a viral, neurologic, or autoimmune cause. But no one has established a definitive link to any specific reason. Ongoing investigation continues.
Any form of the syndrome can include tinnitus or ringing in the ear. Hyperacusis can present in one or both ears and can vary in intensity. The duration of symptoms can be transient, recurrent, long-term, or even permanent.
People with hyperacusis do not necessarily experience hearing loss. However, many report sound distortion, mainly if tinnitus is also present. In addition, the difficulty understanding spoken words, the discomfort of incidental background noises, and, for some, the risk of a panic attack create social isolation.
Lack of interpersonal interaction further contributes to the risk of depression. Once depression was thought to be a risk factor for hyperacusis. However, current theory suggests depression is a result, not a precipitating event, of the condition.
Understanding ‘acusis’ to understand hyperacusis
The process of hearing requires the conversion of energy. Sound waves turn into neural impulses in the middle ear. But, first, sound waves are collected by the external ear and funnelled into the ear canal.
The ear canal condenses the sound waves. A membrane stretches across the end of the channel, forming an airtight and watertight barrier to the inner ear chamber. The first of three little bones that rock each other presses on the membrane from the inside.
Airwaves from sound vibrate the eardrum, which vibrates the Malleus, the first bone. That rocks the Incus, the second bone, and ultimately the third bone: the stapes. The stapes press against a semi-rigid fibrous window to the cochlea.
The cochlea is a small, shell-shaped structure filled with perilymph, a thick mucus-like substance. Ciliary hairs line the cochlea; each strand terminates into a tiny neuron. The neurons join together to form the acoustic nerve.
The vibration of the Stapes against the cochlear window sets the perilymph in motion. Next, the movement of the thick fluid stimulates the hairs. The hairs then produce neurotransmitters in the neurons. Finally, the sensory nerve transmits impulses from the cochlea to the brain for processing.
Where in the hearing mechanism does hyperacusis develop?
The exact mechanism of dysfunction that results in hyperacusis is unknown. More than one process accounts for all cases where hyperacusis is associated. Looking at the clinical presentation can sometimes indicate where hearing is being affected.
The two most common causes of hyperacusis are advanced age and repeated exposure to loud sounds. There is damage to cochlear hairs in both cases. However, this finding is not present in cases unrelated to age or sound volume exposure.
Eight cranial nerve (auditory nerve) microvascular compression syndrome, viral or autoimmune damage can produce the condition. In addition, individuals on the autism spectrum have a higher incidence of hyperacusis. It may involve the limbic system.
The limbic system controls emotional and physical responses to external stimuli. One theory is that overstimulation of the limbic system in autism results in an exaggerated response to sound. Testing reveals that people on the autism spectrum hear the same decibels as nonautistic individuals.
Could the limbic system play a role in panic hyperacusis? Over twenty conditions and disorders are not primarily related to the sense of hearing and have hyperacusis as a symptom. One day, medical professionals will discover how each associated issue alters hearing perception, but in the meantime, research continues.
Is there a cure for hyperacusis?
Unfortunately, there is no cure for hyperacusis. However, there is an approach to help control the damage of hearing too loudly. Contact a hearing clinic to start controlling the damage and gain relief. The first step is to correct any underlying medical or emotional pathology that may be contributing.
Therapy consisting of acoustic retraining and counselling has effectively reduced symptoms to tolerable levels.
Acoustic therapy involves progressive sound exposure coupled with relaxation techniques. The desired result of counselling and sound therapy is minimizing the patient’s response to a hyperacusis episode.
These methods can prove beneficial to mitigate the symptoms of hyperacusis, improving the quality of life for those suffering from this affliction.
Ellen Diamond did her degree in psychology at the University of Hertfordshire. She is interested in mental health, wellness, and lifestyle.
