How To Define Hyperacusis

Most people have probably never even heard of hyperacusis.  It probably sounds to most like some esoteric word used only by the elite scientific world.  However, if you had hyperacusis, you would understand the word thoroughly and hear it loud and clear. 

At least, it would be easy for you to define hyperacusis in its least complex terms.  It is, simply put, a condition in which noises sound extremely louder to you than they are or than they do to others.  If you’ve ever experienced a “fight or flight” response to a dangerous situation, you may have experienced global hypersensitivity.  This is the exaggeration of all sensory perceptions.  In hyperacusis, only one perception is affected.  This results in hearing sensitivity.

The process by which this happens begins with sound that enters the ear.  The sound will travel along the auditory nerve as usual.  Within the sound are many complex messages that are decoded as the sound travels in the brain.  When the sound patterns reach the brain, the sound is heard.

The first thing that happens to the sound information is that unimportant, or background noise, is separated from the more important part of the sound.  What is background and what is important has little to do with the strength of the signal.  Just think of hearing your name spoken softly in a loud place.  You don’t consider that background noise. 

Then, if you have hyperacusis, misphonia and phonophobia interact with the autonomic nervous system and the limbic system in interpreting that sound.  Misphonia, by the way, is a strong dislike of a certain sound.  Think fingernails on chalkboards or any kind of music you hate.  Phonophobia is fear of sound.  This fear tends to increase as hyperacusis increases. 

The second thing that happens is that the important noise is enhanced.  In hyperacusis, all noise is enhanced.  Unless the sounds are actually of a high decibel level and are harmful to anyone’s ears, these noises will not cause damage to your ears.  It is simply a hearing hypersensitivity, not an actual threat of hearing loss.

A distinction should be made between hyperacusis and a condition associated with hearing loss called recruitment.  In recruitment, loud sounds are too loud and soft sounds are too soft to hear.  In hyperacusis all sounds seem too loud.

There seems to be no physical damage that causes this condition.  To define hyperacusis is only to describe the methods by which messages are received and processed in the brain.  To live with it is another story.