The middle ear or tympanic cavity is an irregular, laterally compressed space within the temporal bone. It is filled with air, which is conveyed to it from the nasal part of the pharynx through the auditory tube. It contains a chain of movable bones, which connect its lateral to its medial wall, and serve to convey the vibrations communicated to the tympanic membrane across the cavity to the internal ear.
The tympanic cavity contains a chain of three movable ossicles, the malleus, incus, and stapes. The first is attached to the tympanic membrane, the last to the circumference of the fenestra vestibuli, the incus being placed between and connected to both by delicate articulations.
The Muscles of the Tympanic Cavity (musculi ossiculorum auditus) are the Tensor Tympani and Stapedius. They contract to dampen the amplitude of vibrations from the eardrum to the inner ear.