Sounds are everywhere, and you have two cool parts on your body that let you hear them all: your ears! Your ears are in charge of collecting sounds, processing them, and sending sound signals to your brain. The ear is made up of three different sections: the outer ear, the middle ear, and the inner ear. The air-filled middle ear transforms sound waves into vibrations, protecting the inner ear from damage. The sound waves enter the ear canal, which amplifies the sound into the ear drum. The vibrations of the ear drum cause oscillations in the three bones in the middle ear, the last of which sets the fluid in the cochlea in motion. Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum. The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. The sound vibrations cause the fluid inside the cochlea to ripple, and a traveling wave forms along the basilar membrane.
Sound vibrations move from the eardrum through the ossicles (bones in the middle ear) to the cochlea. Sound vibrations cause the fluid and tiny hair cells inside the cochlea to move. First, sound waves enter the outer ear and pass into the ear canal where the waves cause the eardrum to vibrate.
How Hearing Works