The human body is capable of amazing restorations. From paper cuts, to severed fingers, repair is usually feasible, but why does hearing seem to just get worse?
The answer lies in the fact that most body cells are being constantly replaced; they die out and are replaced by new cells. But, mammals are only born with a set number of hair cells, the cells responsible for auditory sensation in the ear, and they are never replaced.
The hair cells are so called because they are topped with structures called stereocilia that look like tiny hairs. The hair cells make up the organ of corti which is inside of the cochlea, a spiral shaped and lymph-filled structure in the inner ear.
The mechanical vibrations of sound strike your ear drum and are passed on to the cochlea via a number of mechanisms then the hair cells receive the mechanical signal and convert it into an electrical signal that is sent to the brain via the auditory nerve (or cochlear nerve).
Because the hair cells, specifically the stereocilia, receive mechanical signals the mechanical motion can cause them to be damaged or broken. Much like if you take a broom and use it often enough the bristles will begin to crack or fall out, over time the same thing happens to stereocilia. This is why we generally lose hearing with old age.
It’s in the ear
Why then do you need to protect your ears when hunting if hearing may just go anyways? Well, sound pressure is measured in decibels. The hair cells in the human ear detect sound pressure as how loud a sound is. A higher sound pressure, or greater decibel, means a louder sound.
The stereocilia can safely detect sound pressures of up to about 85 decibels, and anything above that has a high likelihood of damaging your hearing depending on the exposure time.
At about 100 decibels your ears can manage for around 15 minutes before damage begins to occur. Above that and the exposure time before damage gets lower and lower. Continuing with the broom metaphor, normal use will wear it out over time, but taking it and pressing against the floor as hard as you can is going to cause some damage right off the bat.
For reference, a gun shot is generally around (depending on the caliber) 140 – 190 decibels. To top it off, the origin of the sound is right there near your ear. So, every time you take a shot without ear protection you’re exposing your ear to an amount of sound pressure nearly twice as high as the stereocilia can take. At this volume your ears suffer damage instantaneously.
The folks at Estes Audiology in Central Texas have been working to help people, hunters or not, find ways to protect and preserve their hearing, and even get it back after damage has been done. Check out their website for more.
More from Wide Open Spaces:
If you don’t protect your ears already, do it now. Every shot you take without protection is causing damage.
What do you think is better, hearing the shot go off as you nab a nice buck now, or hearing your kids and grandkids yell with joy because they nabbed one themselves?