The word “hyperacusis” literally means excess hearing. The name combines the Greek prefix “hyper,” which means “over,” implying excess or exaggeration, with “akousis,” which means hearing and is the root word of “acoustic.”
Hyperacusis is a life-altering hearing condition that causes one to experience loudness intolerance or increased sensitivity to noise. It’s typically a condition that someone is not born with but develops, either gradually or suddenly, as a result of the following causes, per the American Academy of Otolaryngology–Head and Neck Surgery:
Ear damage from toxins or medication
Viral infections involving the inner ear or facial nerve (Bells palsy)
Temporomandibular joint (TMJ) syndrome
Hyperacusis affects an estimated one in 50,000 people and can occur either unilaterally (in one ear) or bilaterally (in both ears). Reactions to noise may result in feelings of discomfort, covering ears, tension, anger, anxiety, and pain.
Those who live with hyperacusis face aversion to everyday sounds at decibel levels that do not bother others, such as: running water, car engines, conversations, kitchen appliances, voices speaking on the telephone, bicycle pedals, crunching leaves, or vacuum cleaners.
Because individuals with hyperacusis are not able to tolerate noises like those listed above, their quality of life is compromised. They experience great difficulty moving about, traveling, and communicating with others. Consequences can include social isolation, anxiety, depression, lack of concentration, and insomnia.
Hyperacusis is distinct from tinnitus (ringing in the ears), but there is a high degree of comorbidity between them. An estimated 86% of hyperacusis patients also have tinnitus and 30–40% of tinnitus patients also show symptoms of hyperacusis. It has been speculated that tinnitus and hyperacusis have a shared etiology or might exist due to the same pathological mechanism.
Sources: American Academy of Otolaryngology–Head and Neck Surgery; Hyperacusis Network; National Health Service; Frontiers in Neurology