The auditory ossicles (the incus, malleus, and stapes) are the bones of the middle ear. The incus is shaped like an anvil. The malleus is shaped like a hammer and the stapes is shaped like a stirrup. They are the smallest bones in the human body. The three bones are connected to each other by hinges and act as mechanical levers to carry and push the vibrations of the ear drum forward to the flexible membrane of the oval window. When sound waves cause the tympanic membrane to vibrate, the vibrations move the malleus, which in turn moves the incus. The incus moves the stapes which is attached to the oval window. The sound is then passed to the inner ear. The leverage of the middle ear bones increases the intensity of the sound wave by five decibels before the wave is funneled toward the oval window. Research Auditory Ossicles
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Abbreviations
Research Auditory Ossicles
