NOISE-INDUCED HEARING LOSS (NIHL)
When we are exposed to sounds that are too loud or loud sounds that last a long time, sensitive structures in our inner ear can be damaged, causing noise-induced hearing loss (NIHL). These sensitive structures in our inner ear, called hair cells, are small sensory cells that convert sound energy into electrical signals that travel to the brain. Once damaged, our hair cells cannot grow back.
NIHL is typically caused by a one-time exposure to an intense sound, such as an explosion or gunfire, or by an extended exposure to loud sounds, such as working in a stamping plant for years with no ear protection. Exposure to these harmful sounds causes damage to the hair cells as well as the auditory, or hearing, nerve. Often, one-time exposure to an intense sound is associated with a temporary hearing loss and tinnitus (buzzing or ringing) in the ear. This may be permanent or may resolve over several days. Continuous exposure to loud noise can damage the structure of hair cells and cause hearing loss and tinnitus. This process is typically more gradual, occurring over years.
When a person is exposed to loud noise over a long period of time, symptoms of NIHL often increase gradually. Over time, the individual with NIHL may have more difficulty understanding speech. The individual may not be aware of the hearing loss, though, as it may occur very gradually and thus is not noticeable to the patient.
NIHL can be easily prevented:
Treatment of NIHL includes hearing aids and assistive listening devices. These devices allow the individual that is affected by NIHL to improve their hearing and to decrease the negative effects of their loss of hearing.