Hearing acuity in humans, with age, gradually decreases. And accelerates this process – the modern way of life, which everywhere imposes upon the person an avalanche of all sorts of noises and sounds.
Experts say that about 75% of cases of hearing loss associated not only with aging, but noise exposure suffered by people throughout life. How to protect yourself from hearing loss? To understand this, we need to understand how the organ of hearing.
The function of the organ of hearing:
The auricle or outer part of the outer ear collects sound waves and directs them in the ear canal. Through the auditory canal the sound waves reach the eardrum and make it vibrate. The eardrum causes vibrations of the three auditory ossicles of the middle ear, which are transmitted to the inner ear, consisting of cavities and channels filled with liquid. Using fluid vibrations are transmitted to the cochlea, which includes hearing voloskovye cells. Then a liquid medium of the cochlea stimulates the outer hair cells, and sound vibrations are converted into nerve impulses that are transmitted to the brain, it decodes and as a result, we hear sound.
The task of the brain is part of the definition of sound, which of them should be to respond to and which to ignore. For example, when the child during the game makes sounds, the mother may not pay attention to them, but if she hears a frightened cry of a child, I immediately react. Listening with two ears, the stereo effect is obtained, we can determine the position of the sound source. But if we listen to it, the brain at once can perceive only one message. Therefore, when a person is talking on the phone, he immediately could understand what he said to those around him.
The organ of hearing and noise level:
The noise level is getting higher in our environment. On the organ of hearing many people’s day-to-day impact sounds of different intensity – the noise of cars, trucks, crashing production of electrical equipment.
Sometimes we do include excessively loud sound, sparing your hearing. Many listen to music through headphones. According to research conducted in the United States and Canada, it became clear that a hearing is because they are using headphones listening to very loud music.
But what volume is considered excessive? The sounds that we hear are characterized by duration, frequency and intensity. The duration of a sound is determined by the length of time during which a sound is heard. Under the frequency of sound means the number of oscillations per second and measured in Hertz. The human ear can perceive frequencies from 20 to 20,000 Hertz.
The intensity of the sound is determined by its volume and is measured in decibels (dB). For example, a typical conversation with average volume level reaches 60 dB. The hearing experts believe, if the volume exceeds 85 dB, then the longer is the exposure, the greater subsequently reduced hearing. For example, the sound of the drill 100 dB for 2 hours a person can withstand without damage to the ears, but inside the video game, where the noise level is 110 dB, it can be no more than 30 minutes. When you increase the volume level by 10 dB, 10 times increases its impact on the organ of hearing. If the volume level is about 120 decibels, the sound is already pain. For comparison, the stereo sound of the instrument is 140 dB.
How does the hearing:
To understand how loud sounds disturb the ear, will help such an example. The hair cells of the inner ear can be compared to the wheat field, and entering the ear sound waves with the wind. The breeze slightly swaying the tops of the ears without harm to the wheat, but the wind bent the stalks stronger. A strong sudden gust or strong wind blowing for a long time may damage the wheat.
Similarly, sensitive hair cells are exposed to noise. From the sudden sound damaged tissue of the inner ear and left scars, which lead to irreversible hearing damage. Hair cells can suffer and long-term intense noise exposure, and they are not restored. The consequence of exposure to the noise can be ringing, buzzing or roaring in the ears and head.
Hearing loss can sometimes occur due to injury or unfortunate heredity.
How to protect and preserve hearing:
People in a position to do a lot to protect and preserve your hearing for as long as possible, it is important to know the potential danger.
If you are using stereo headphones, then set the sound at a volume that you could hear the surrounding sounds. If in the car or at home because of the volume of the stereo equipment you can’t hear what the interlocutor says, the noise is harmful to hearing.
The hearing experts warn that the sound is 90 dB for 2-3 hours is detrimental to hearing. In noise, it is recommended to use earplugs (ear plugs).
Parents must remember that kids unlike adults hearing more vulnerable. On the hearing of children can adversely impact the noise from toys. For example, conventional rattle may come from the noise of 110 dB.
The organ of hearing – a small and delicate instrument through which we perceive many different sounds from the outside world, including and very beautiful. It deserves careful handling!
The volume level of some sounds:
– A gunshot is 140 decibels
– Jet – 120 decibels
Band saw – 110 decibels
– Train 100 decibels,
Mixer 90 decibels,
– Transport in rush hour – 80 decibels
– Conversation – 60 decibels
– A whisper is 20 decibels
– Breathing is 10 decibels.
When ear drops:
· People are constantly asking;
· Includes loud TV, which irritates others;
· When talking strains to hear, leans forward, turns his head to hear;
· Hard of hearing when around noisy and crowded;
· Can’t hear what he said and asks the other.