This can gradually reduce your ability to understand speech in noisy places. Eventually, if hearing loss continues, it can become hard to understand speech even in quieter places. In addition to damaging hair cells, noise can also damage the auditory nerve that carries information about sounds to your brain.
Early damage may not show up on your hearing test. The effect of loud noise over time affects how well you might hear later in life. It also affects how quickly you might develop hearing problems, even after exposure has stopped.
We hear sound because of vibrations sound waves that reach our ears. We recognize those vibrations as speech, music, or other sounds. Outer Ear The outer ear—the part of the ear you see—funnels sound waves into the ear canal. The sound waves travel through the ear canal to reach the eardrum. Middle Ear The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones amplify, or increase, the sound vibrations and send them to the inner ear.
Inner Ear The inner ear contains a snail-shaped structure filled with fluid called the cochlea. Sound vibrations create waves in the cochlear fluids. The more you are around loud noises, the more you risk having hearing loss. Whether noise harms your hearing depends on the loudness, the pitch, and the length of time you are exposed to the noise.
The loudness of a sound measured in decibels, or dB and the length of exposure are related. The louder the sound, the shorter the exposure can be before damage occurs.
Using power tools at about dB , listening to loud stereo headsets at about dB , attending a rock concert at about l20 dB , or hearing a gunshot at to dB may damage the hearing of some people after only a few times. One reason people fail to notice the danger of noise is that too much exposure to noise causes few symptoms.
Hearing loss is rarely painful. The symptoms are usually vague:. This is not really true. Even if there are no more symptoms, some of the cells in the inner ear may have been destroyed by the noise.
Your hearing returns to normal if enough healthy cells are left in your inner ear. But you will develop a lasting hearing loss if the noise exposure is repeated and more cells are destroyed.
The first sign of a noise-induced hearing loss is not hearing high-pitched sounds, like the singing of birds. It may also be not understanding speech when in a crowd or an area with a lot of background noise.
If the damage goes on, hearing declines further, and lower pitched sounds become hard to understand. The human ear is divided into 3 parts — the external, middle, and inner ear. The inner ear is located inside the skull. It is the most complex part of the ear. The soft tissue of the inner ear is made of different types of cells and nerves, all arranged in a pattern on a thin sheet of tissue.
Large tubes filled with fluid surround the soft tissue of the inner ear. Hearing loss occurs when the inner ear is damaged. Frequent exposure to loud or moderately loud noise over a long period of time can damage the soft tissue of the inner ear.
Cells and nerves in the inner ear are destroyed by continuous or repeated exposure to loud sounds. If enough cells and nerves are destroyed, hearing is permanently damaged. Your doctor can offer a hearing test that will determine if you have a hearing loss. If the test shows that you do have a hearing loss, you will be referred to an audiologist ear care and hearing loss professionals or otolaryngologist a doctor with special training in ear and hearing disorders for a more thorough hearing test.
This test will determine what degree of hearing loss you have mild, moderate, or profound. Think of the many sounds at different volumes you hear in a day, a week, or a year. The effects of loud sounds add up over a lifetime. Because the damage from noise exposure is usually gradual, you might not notice it, or you might ignore the signs of hearing loss until they become more serious. Over time, sounds may become distorted or muffled. You might find it difficult to understand people when they talk, or you might turn up the volume on the TV.
The damage from NIHL can lead to hearing loss serious enough that you need to make sounds louder with devices like hearing aids, to help you hear, communicate, and participate fully in daily activities. The good news is that you can prevent NIHL. By teaching children healthy hearing habits, you can help them keep their hearing too. You hear because of a series of steps in your ear that change sound into electrical signals. Top of Page. The effect of lower noise levels over long periods is the same as louder noise levels over a shorter period.
You can use a sound level meter SLM to measure noise around you. Free SLMs developed as smartphone apps are available. The U. The EPA also specified limits for speech interference and annoyance at 55 dBA for outdoors activities and 45 dBA for indoor activities.
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