In modern medicine, hearing loss caused by earphones or loud environments is called noise-induced hearing loss. Inside our ears, in a tiny organ called the cochlea, there are tens of thousands of delicate cells that detect sound, known as hair cells. These hair cells convert the vibrations of fluid in the inner ear's cochlea into electrical signals and transmit them to the brain, capturing sound signals much like tiny antennas.
However, when exposed to excessively loud and continuous noise, these hair cells become physically damaged or begin to experience functional abnormalities. Imagine delicate blades of grass in a field that need to sway in the breeze to grow; if a sudden storm sweeps through, the grass breaks and is ruined. The hair cells in our ears are just the same. Regrettably, once damaged, hair cells do not regenerate. Therefore, noise-induced hearing loss mostly leads to irreversible damage that cannot be undone.
The muffled sensation or ringing sound in the ears immediately following noise exposureβa temporary threshold shiftβcan recover if the ears are given rest. However, if this recurs chronically or if exposure to severe noise continues, it develops into a permanent threshold shift, which is permanent hearing loss. In particular, because damage begins in the high-frequency range, one may initially feel no major inconvenience in conversation, but it can progress gradually through missing sounds at certain frequencies or finding conversations in noisy places difficult.
Furthermore, the ears are not merely organs for hearing sound; they are closely connected to our body's blood circulation, nervous system, and endocrine system. If stress is severe or blood circulation is poor, microvessel blood flow to the cochlea decreases, which may prevent a smooth supply of oxygen and nutrients needed by hair cells. In modern terms, the deficiency of kidney essence mentioned in Donguibogam can actually be linked to a decline in our body's overall metabolism, stress management, and blood flow. Healthy ears begin with a healthy body. Please remember that once hearing is lost, it is difficult to regain.
