Hearing is the sense by which sound is perceived. Our brains differentiate between sounds by recognising differences in volume (intensity) and pitch (frequency). As we develop from infanthood, we are constantly listening to sounds and speech around us. As our brains begin to attach meaning to sound we learn to recognise sounds and voices and then learn to understand the meaning of words and speech. After much listening, we begin to learn to speak. In this way, hearing is necessary for the normal development of spoken language which is an essential part of communication.
How do we hear?
In order to hear normally, a complete and clear signal must be transmitted to the brain from the external environment via the outer ear, middle ear, inner ear and hearing nerve.
Sound is gathered by the outer ear and sent down the ear canal to the eardrum. The sound causes the eardrum to vibrate which sets the three tiny bones in the middle ear into motion. The motion of the bones causes the fluid in the inner ear to move. The movement of the inner ear fluid causes the hair cells in the cochlea to bend. The hair cells proceed to change the movement into electrical pulses. These electrical impulses are transmitted to the hearing (auditory) nerve and up to the brain, where they are interpreted as sound.
Any damage or defect to the anatomy or physiology of the auditory system results in the ear not getting a clear or complete signal - that is a hearing loss.
The impact of hearing loss on a child will vary depending on the age of the child, when the hearing loss began and the severity of the hearing loss.
To find out more click on the links below:
- Do you have concerns about a child's hearing
- Read further on how a hearing loss may affect a child's development.
- Find out about the different types of hearing loss
- There are also different degrees of hearing loss