The miracle of hearing
The human hearing system enables us to perceive pressure fluctuations in the air as tone or noise. These types of vibrations are referred to as sound. When the eardrum is hit by sound waves, their movements are transmitted to the cochlea through the auditory ossicles known as the hammer, anvil and stirrup. The cochlea is a coiled part of the inner ear, a pea-sized structure which contains around 25,000 tiny sensory hairs suspended in fluid. These sensory hairs convert sound vibrations into bioelectric signals in the cochlea. In this way, sound waves are converted into sounds of the sea, language or symphonies.
1. Hammer, 2. Anvil, 3. Stirrup, 4. Semicircular canals of the organ of equilibrium, 5. External auditory canal, 6. Eardrum, 7. Cochlea, 8. Eustachian tube