How Do Human Beings Talk?

The man has ability to speak. This is due to a great extent to the way in which the larynx is made. Larynx, is a hollow organ and is almost of box like shape. It is the enlarged part like of the windpipe. The walls of this ‘box’ are made of cartilage and they are lined inside with mucous membrane.

The mucous membrane becomes thicker and projects form wall into centre of the box. This happens only at one place on each side. These projections are ‘Vocal Cords’. Each cord is moved by many small muscles. With the entry of air into the mouth, from lungs, it passes between the two vocal cords and makes then to vibrate. This produces a sound.

What kind of sound? It depends on the tension and position of these vocal cords. The muscle system controlling the cords is the most delicate muscle system in the entire body to make possible all type of sounds that we produce. In actual, the vocal cords can assume as many as 170 different positions.

With the vibration of vocal cords, the column of air that is in the respiratory passage is made to vibrate. We in practice hear the vibration of this air column. If the vocal cords are not too tensed, long waves are formed and we hear deep tones. In the event of tension of vocal cords, the vibrations are rapid, so short waves are produced and we hear high tones. When boys reach the age of about 14, the larynx cords become thicker and thus the pitch of the voice is lowered. The change of pitch is called “Change of voice”.

We see that our pitch of voice is controlled by the tension of the vocal cords. Now, let us know about the tone. The resonating spaces determine the tone. It is similar to the case of a violin, in which tone is determined by the vibration of the entire instrument. When we sing or speak, the resonating spaces involved include the wind-pipe, the lungs, the thorax and also the spaces in our nose and mouth. The vibration of air in all of them helps to decide tone.

This is not all. Our chest, abdomen, diaphragm, tongue, palate, lips, teeth, etc. all come into the picture. All are concerned in producing sounds and letters. The process of speaking is like playing on a very complicated and difficult musical instrument. It is only because we learnt it at an early stage of life in childhood and have practiced it all through, that enables us to speak nicely.