How Do we Hear?

Hearing is an amazing process that happens for us without consciously thinking about it. There is a tremendous amount of processing that happens in the brain, and it all happens in fractions of a second.

Although hearing really happens in our brain where the sounds we hear are interpreted into meaningful information, it starts at the outer ear as sounds enter our ears as acoustical energy.


1. Sound is transmitted through the air as sound waves from the environment. The sound waves are gathered by the outer ear and sent down the ear canal to the eardrum.

2. The sound waves cause the eardrum to vibrate, which sets the three tiny bones in the middle ear into motion.

3. The motion of the three bones causes the fluid in the inner ear, or cochlea, to move.

4. The movement of the fluid in the inner ear causes the hair cells in the cochlea to bend. The hair cells change the movement into electrical impulses.

5. These electrical impulses are transmitted to the hearing (auditory) nerve and up to the brain, where they are interpreted as sound.