1. Sound Reception:
* Sound waves travel through the air and reach the outer ear (pinna).
* The pinna channels these sound waves into the ear canal, where they vibrate the eardrum (tympanic membrane).
2. Transmission and Amplification:
* Vibrations from the eardrum are transmitted to three tiny bones in the middle ear (malleus, incus, and stapes).
* These bones amplify the vibrations and transmit them to the inner ear.
3. Fluid Vibration and Hair Cell Stimulation:
* The stapes vibrates against a membrane called the oval window, setting the fluid in the cochlea (inner ear) into motion.
* This fluid movement bends tiny hair cells within the cochlea.
4. Signal Transduction:
* The bending of hair cells triggers a chemical signal that is transmitted to the auditory nerve.
5. Brain Processing:
* The auditory nerve carries the signal to the brain, where it is interpreted and processed as sound.
Therefore, hearing is not simply a passive process but a complex interplay of mechanical, chemical, and neurological events. It allows us to perceive the world through sound, providing us with information about our surroundings and enabling us to communicate, enjoy music, and much more.