Hearing is complex, requiring a series of actions and reactions to work. The process involves many parts of the ear working together to convert sound waves into information the brain understands and interprets as sounds.
- Sound waves enter the ear canal and travel toward our eardrums.
- These sound waves cause the eardrum and bones in the middle ear to vibrate.
- Tiny hair cells inside cochlea (inner ear) convert these vibrations into electric impulses/signals that are picked up by the auditory nerve.
- At birth, each normal ear has about 12,000 sensory cells, called hair cells, which sit on a membrane that vibrates in response to incoming sound. Each frequency of a complex sound maximally vibrates the membrane at one location.
Because of this mechanism, we hear different pitches within the sound. A louder sound increases the amplitude of the vibration, so we hear loudness.
- Signals sent to the brain from auditory nerve are then interpreted as sounds.