Hearing

The human ear is divided into 3 main functioning groups:

The outer ear

The middle ear

The inner ear.

1. Sound travels in waves. These waves or vibrations are collected by the outer ear (pinna) and directed into the ear canal.

2. The sound waves cause the eardrum to vibrate. The eardrum is connected to 3 small bones in the middle ear – the malleus, incus and stapes. These 3 bones form the ossicular chain.

3. When the eardrum vibrates, these bones start a ‘piston’ like motion that presses or pushes onto the oval window. The oval window is the doorway to the cochlea. The cochlea or inner ear is a snail shaped organ filled with fluid.

4. Pushing from the ossicles creates a wave like phenomena inside the cochlear. This makes the basilar membrane move and activates thousands of tiny hair cells attached to the auditory nerve.

5. Sensitive hair cells are triggered by different frequencies (pitches) of sound.

6. The hair cells generate electrochemical signals which travel along the auditory nerve to the brain. The signals are processed in the brain and recognised as sound.