Anatomy of the ear

The ear consists of three main parts:

  • The outer ear
  • The middle ear
  • The inner ear

The outer ear

 

  • The pinna collects and funnels sound into the ear canal.
  • The ear canal carries sound to the eardrum, a thin membrane that separates the canal and the middle ear.

 

 

 

 

 

The middle ear

 

  • The eardrum changes sound into vibrations.
  • These vibrations set in motion a chain of three small bones (ossicles) – hammer, anvil and stirrup. The ossicles transfer vibrations to the cochlea in the inner ear.

 

 

 

 

The inner ear

 

  • The cochlea contains fluid which begins to move, stimulating highly sensitive hair cells (cilia) which  in turn create electrical signals .
  • Hair cells at one end of the cochlea send low pitch sound information, and hair cells at the other end send high pitch sound information.
  • The auditory nerve picks these electrical signals and carries them to the brain.
  • The brain interprets the electrical signals as sounds.