Sound waves are captured by the outer ear and cause the eardrum (tympanic membrane) to vibrate. These vibrations are transmitted via three connected bones: the hammer (malleus), anvil (incus), and stirrup (stapes). The vibrating stirrup tap-tap-taps on the oval window and causes fluid inside the cochlea to pass the vibrations on to the basilar membrane and organ of Corti, which is covered in thousands of microscopic sound receptors (hair cells). From there the vibrations are turned into electrical signals and passed on to the brain for interpretation. Note: The cochlea is shown stretched out here like a straight tube. In reality, it is curled up like a coil. (Alila Medical Media/ Shutterstock) Read More