by Daniel Fink, MD, Chair, The Quiet Coalition
Loud noise exposure, such as at a rock concert or after using a noisy appliance or power tool, causes temporary auditory symptoms such as muffling of sound. If hearing testing–audiometry–is performed, a phenomenon known as noise-induced temporary threshold shift (TTS or NITTS) is also found. This is a decrease in hearing that usually resolves over time.
The reason the temporary auditory symptoms or TTS occurs has not been understood, but new research done at the University of Southern California’s Keck Medicine of USC, shows that the cause is probably a buildup of fluid in the inner ear, technically known as endolymphatic hydrops.
The study was done on mice, using a technique known as optical coherence tomography to measure the fluid buildup in the cochlea. Application of concentrated salt solution–hypertonic saline–appeared to help resolve the condition and prevent permanent nerve damage.
The research needs confirmation by other researchers, and animal research may not be directly translatable to humans even when the research animal has almost the same genetic material as humans, but it’s exciting to know that science continues to advance.
Of course, no further research is needed to know that noise damages hearing, that noise-induced hearing loss is 100% preventable, or that prevention of noise-induced hearing loss is easy.
All one has to do is avoid loud noise, leave the noisy environment or move away from the noise source, or use hearing protection.
Because if something sounds loud, it’s too loud, and one’s hearing is at risk.