Hyperacusis is a hypersensitivity to everyday sounds which may be perceived as painfully loud. In extreme cases, it may lead to complete social isolation to avoid any contact with sounds. It may present as a single entity not associated with any other hearing symptoms.
The diminished tolerance to normal environmental sounds may vary from a mild to very severe discomfort with sounds which are not perceived as loud by other people.
Hyperacusis can also be accompanied by ear pain and tinnitus. In extreme cases of hyperacusis, individuals isolate themselves into confined, quiet environments, away from social interaction.
Is Hyperacusis a Hearing Loss?
Individuals with hyperacusis do not necessarily have a hearing loss, and it is also a fallacy that they may have “supernormal hearing”.
Hyperacusis can be caused by trauma or insult to the brain causing an alteration in the central processing of sounds. This alteration may be chemically induced by toxic drugs, or mechanically induced by head injuries. It can also be caused by psychological traumas.
Our perception of loudness is not dictated solely by the strength or intensity of the sound entering our ears. It is also influenced by the meaning of the sounds and learned association in the central areas of the brain.
Over-sensitivity to a sound may begin with an irrational fear, and the central auditory processing mechanism becomes trained to listen and monitor minor sounds, which turns them into very loud, intrusive and unpleasant sounds.
An Audiology Assessment can Help with the Best Treatment Plan for Hyperacusis
Audiologists can assess the loudness of this condition by measuring loudness growth or loudness discomfort levels with pure tones, although some studies use actual recordings of environmental sounds.
Hyperacusis appears to result from reduced nerve input and response to sound. As a result, the brain has no choice but to increase gain, causing over-amplification in its attempt to compensate. The audiologist can assist to further understand the individual causes.
The audiologist can help to understand how the brain is dynamically changing in response to the environment and the pathological conditions in the ear.
The scientific studies and experience of Dr Celene McNeil and her colleagues can be found on our Audiology Publications page.
Tonic tensor tympani syndrome in tinnitus and hyperacusis patients: a multi-clinic study