How We Hear

Our sense of hearing is precious. It keeps us connected to our world and to those we love.

“ The problems of deafness are deeper and more complex, if not more important, than those of blindness. Deafness is a much worse misfortune. For it means the loss of the most vital stimulus–the sound of the voice that brings language, sets thoughts astir and keeps us in the intellectual company of man.” (Helen Keller)

Our sense of hearing is an incredibly complex and efficient system.

When working normally, it can detect and distinguish between many thousands of sounds.

Sound is produced by vibrations in the air and these travel out away from the source.

Our hearing mechanism collects, transforms and transmits these sound waves as messages to our brain and our brain then interprets the message.

The message has to pass through 3 well-defined parts of the ear known as the Outer, Middle and Inner ear.

Ear DiagramThe outer ear serves as a sound collector, and directs sound vibrations down towards the eardrum. The walls of the ear canal produce wax or cerumen which is an important part of ear health. It serves to lubricate and protect the ear, minimize the entry of foreign bodies and insects into the ear, and has mild anti-bacterial and anti-fungal properties.

The sound vibrations cause movement of the eardrum which is connected to a chain of 3 tiny bones (ossicles) which comprise the middle ear. The middle ear system is a`mechanical system which intensifies the energy of the sound waves to deliver them to the inner ear (cochlea).

Once received by the inner ear, an intricate system of hair cells create electro-chemical impulses which travel along the hearing nerve to the brain, where they a recognized as sounds.