OUR SENSE OF HEARING 

It is noted that more than 120 million people all over the world have ear problem according to WHO. 

We need to protect our hearing system as it was freely given as such should be taking as a great treasure. The precious part of the body responsible for our hearing called ear reduces its effectiveness according to ageing. The noise and sound polluted world of ours is responsible for the incessant hearing problem of many in the world today; hence such pollution should be avoided. The scientist said that 75 percent of hearing the loss in the world and American, in particular, is not only caused by the ageing process but by what you have done to our ears throughout the lifetime.

Loud sounds and heavy noisy machines or explosions are capable of destroying the eardrum that is responsible for hearing. During our various jobs in our quest for ends to meet, accumulatively affect us cumulatively and gradually.

What is one expected to do as precaution measure in other not to be the victim, as much should take care of to avoid damage in future, that is why knowledge of the functionality if necessary and worthwhile. 

HOW DOES IT FUNCTION

Noise pollution in on the increase in the environment especially those that are in the cities, where exposure to heavy sounds is possible. All along and in daily bases, eardrums are destroyed by sounds of varying intensities ranging from the noise of cars, buses, and trucks in the streets to the racket of power tools in the workplace.

Most times, we own responsibility of this by our way turning up the volume accumulatively. The much-adopted way of listening to music these days is through headphones attached to a portable sound player of which youths are most affected by the loss of hearing sense caused by the use of headphones with the volume turned up. This is also found in party halls and even private homes, where one will order for an increase of sound system for enjoyment. It is in three ways that the enjoyable sound then becomes dangerous; by the length or how often one plays and hear a sound, by frequency, and by also by how loud it is. A sound’s frequency, or pitch, is described in cycles per second, or hertz. The range of audible frequency for normal, healthy hearing is from 20 to 20,000 cycles per second.

The measurement of sound’s amplitude, or strength, is in units called decibels (dB). The normal conversation has a sound level of approximately 60 decibels. Those who studied sound (Audiologists) say that the longer you are exposed to anything louder than 85 decibels, the greater will be the eventual loss of hearing. That is to mean that the louder the sound, the faster the damage to hearing system takes place. It is observed that our ear can safely handle two hours with a power drill (100 dB), but not more than 30 minutes in a noisy video arcade (110 dB). Every 10-decibel increase on the sound scale represents 10 times more ear-battering noise.” Tests confirm that sound becomes painful at approximately 120 decibels. Incredibly, some home stereo equipment can produce sound at more than 140 decibels!—See the accompanying box.

In order for understanding to reach a click about how sounds can damage your hearing system, is wise we consider the transpiration when sound waves reach your ears.

THE FUNCTION OF EAR 

The shape of the fleshy part of the outer ear called the auricle, or pinna, is designed to collect sound waves and direct them into the ear canal, where they soon reach the eardrum. At this point the sound waves cause the eardrum to vibrate, and the eardrum, in turn, causes the three bones in the middle ear to vibrate. Next, the vibrations are transmitted into the inner ear, a fluid-filled sac encased in bone. Here the vibrations move through the fluid in the cochlea, the snail-shaped hearing part of the inner ear that contains the hair cells. The fluid in the cochlea triggers the top portion of the hair cells to produce readable nerve impulses. These impulses are then transmitted to the brain, where they are decoded and interpreted as sound.

The limbic system helps the brain decide which sounds to pay attention to and which to dismiss. For instance, a mother may not consciously hear the normal sounds of a child at play, but she will respond instantly to a cry of alarm. Hearing with two ears enables us to hear in stereo, which is very useful. It allows us to identify where the sounds are coming from. Yet, when a sound consists of speech, the brain can only understand one message at a time. “This is why,” says the book The Senses, “when listening to someone while talking on the telephone, people cannot readily take in what the person next to them is saying.”

How Noise Damages Our Hearing

To visualise how loud sounds can damage our hearing, consider the following analogy. One occupational safety report compares the hair membranes in the inner ear to wheat in a field and the sound entering the ear to the wind. A gentle breeze, like a low-level sound, will move the tops of the wheat, but the wheat is not damaged. Increased wind velocity, however, will increase the stress on the wheat stalk. A sudden, extremely high wind or continuous exposure to lower winds over a long period of time may damage the stalk beyond repair and cause it to die.

It is similar to noise and the tiny, delicate hair cells in the inner ear. An instant loud blast can tear the tissues of the inner ear and leave scars that cause permanent hearing loss. In addition, prolonged dangerous noise levels can permanently damage the delicate hair cells. Once damaged, they cannot regenerate. The accompanying result may be tinnitus—a buzzing, ringing, or roaring in the ears or head.

Protect and Prolong Your Hearing

Although heredity or some unforeseen accident may result in hearing loss, we can take precautions to protect and prolong our precious sense of hearing. It is good to learn in advance about potential hearing hazards. As one audiologist said, “waiting for a problem to arise before taking action is like applying the suntan lotion after you’ve been burned.”

Often it is a matter of how we listen and not so much what we listen to. For example, if you use stereo headphones, you may want to set the volume at a level low enough for you to be able to hear sounds around you. If your car or home stereo is set loud enough to drown out ordinary conversation, this may well be a signal that it is also loud enough to damage your hearing. Experts caution that two to three hours of exposure to 90 decibels can damage your ears. Earplugs or other hearing protection devices are recommended whenever you are in a noisy environment.

Parents do well to remember that children are more susceptible to hearing damage than are adults. Keep in mind the potential danger of noisy playthings. Why a toy rattle can reach 110 decibels!

Our ears are delicate, small, and wonderful mechanisms. With them, we can hear all the varied and beautiful sounds of the world around us. Surely, this precious gift of hearing deserves to be protected.