Tympanic duct Tympanic duct The tympanic duct or scala tympani is one of the perilymph-filled cavities in the inner ear of the human. It is separated from the cochlear duct by the basilar membrane, and it extends from the round window to the helicotrema, where it continues as vestibular duct. The purpose of the perilymph-filled tympanic duct and vestibular duct is to transduce the movement of air that causes the tympanic membrane and the ossicles to vibrate, to movement of liquid and the basilar membrane. This movement is conveyed to the organ of Corti inside the cochlear duct, composed of hair cells
Tympanic part of the temporal bone Tympanic part of the temporal bone The tympanic part of the temporal bone is a curved plate of bone lying below the squamous part of the temporal bone, in front of the mastoid process, and surrounding the external part of the ear canal. It originates as a separate bone (tympanic bone), which in some mammals stays separate through life. Evolutionarily, a portion of it is derived from the angular bone of the reptilian lower jaw. Its postero-superior surface is concave, and forms the anterior wall, the floor, and part of the posterior wall of the bony ear canal. Medially, it