The ear is made up of three parts that work together to process sounds: the outer ear, the middle ear, and the inner ear. Part of the inner ear, called the cochlea, contains tiny hair cells. These hair cells help send sound messages to the brain. Loud noise can damage the hair cells. When this happens, the cochlea can't relay sound messages to the brain as well.Unlike damage to other parts of your body, inner ear damage never heals. Over time, as more and more hair cells get damaged, your hearing will get worse and worse.