Hyperacusis is an abnormal sound sensitivity or decreased sound tolerance, with a heightened sense of volume and physical discomfort from everyday sounds that other people can comfortably tolerate.
Sounds that are typically difficult for people with hyperacusis to tolerate are loud/impact/sustained sounds, particularly if they are unexpected and in close proximity to the ears. High frequency (pitch) sounds tend to be tolerated less well.
Hyperacusis is the consequence of an involuntary sense of threat triggered by those sounds when they are subconsciously processed, often due to those sounds being evaluated as potentially damaging or potentially painful or potentially exacerbating pre-existing aural symptoms such as tinnitus or hearing loss.
When hyperacusis develops:
The consensus is that about 40% of people with troublesome tinnitus have some degree of hyperacusis. Recent large-scale prevalence research, including research carried out at our clinic, has identified the development of secondary hyperacusis in about 50% of help-seeking tinnitus patients.
If acoustic shock symptoms persist after the acoustic incident, it is generally because hyperacusis has developed.
Misophonia and high levels of anxiety can predispose towards hyperacusis development.
Hyperacusis can also develop with:
When hyperacusis develops, loud/impact everyday sounds begin to appear unnaturally prominent and increasingly louder.
Following exposure to these sounds, a temporary increase in tinnitus (if present) and/or hyperacusis may be noticed, and escalating sensations in the ear may develop due to TTTS, such as ear pain, a fluttering sensation or fullness/blockage in the ear.
For many people, explanation and reassurance will allow them to desensitise their hyperacusis successfully.
The factors resulting in hyperacusis are complex and outside a patient’s conscious control, so it is impossible to predict how long hyperacusis will last and desensitisation may not always be achievable.
Significant hyperacusis can cause anxiety, distress, suffering from sound-induced pain and lifestyle constraints.
Hyperacusis can be considered a disability for people affected by their hyperacusis in this way.
Desensitisation requires a personalised understanding of the mechanisms behind the development of hyperacusis and TTTS, such as: