The sound reaching our ears first makes the eardrum vibrate. These vibrations are transmitted through the 3 small bones in the middle ear (hammer, anvil and stirrup) to the cochlea. This results in a movement within the cochlear fluids. Sensitive hair cells in the cochlea register this movement and start a neural activity, which is transmitted through the auditory nerve to the brain. Thus we hear.
Speech is an overlaid function. The sctructures meant for sucking, biting, chewing and swallowing are used for the production of speech cords. The vocal cords in the throat meant to protect the lungs from the foreign bodies are used for production of voice. The exhaled air from the lungs is used to vibrate the vocal cords to produce voice. The voice is produced just like a balloon producing sounds when its mouth is stretched. In this way the structure meant for breathing and eating is used for production of voice and speech. However the brain is the master control. The speech is a co-ordinated activity of respiration, phonation and articulation.
Speech refers to the sounds that come out of our mouth and take shape in the form of words. Many things must happen in order for us to speak, like:
For most children, these processes happen naturally, if proper stimulation occurs without conscious thought.
For some children, this sequence breaks down. Once the source of the breakdown is identified, these steps can be facilitated in a direct and conscious manner.