Quote:
Originally Posted by footfootfoot
I duffed the Eustachian tube. figured it helped hearing rather than balance, I always thought that was an inner ear thing.
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Correct. The Eustachian tube has nothing to do with balance. Balance is maintained by many things in the body interacting together, but concerning the ear, it is the vestibular system which maintains balance:
Input from the vestibular system
The inner ear or labyrinth is a complex series of passageways and chambers within the bony skull. Within these passageways are tubes and sacs filled with a fluid called endolymph. Around the outside of the tubes and sacs is a different fluid—the perilymph. Both of these fluids are of precise chemical compositions, and they are different. The mechanism in your inner ear that regulates the amount and composition of these fluids is important to the proper functioning of your inner ear.
Each inner ear has a hearing (auditory) component—the cochlea, and a balance (vestibular) component—the vestibular apparatus, consisting of three semicircular canals and a utricle and saccule. Each of the semicircular canals is located in a different plane in space. They are located at right angles to each other and to those on the opposite side of the head. At the base of each canal is a swelling (ampulla) and within these ampullae are located the sensory receptors for each canal.
Inside each fluid-filled semicircular canal is a sensory receptor (cupula) attached at its base. With head movement in the direction in which this canal is located, the endolymphatic fluid within the canal, because of inertia, lags behind. When this fluid lags behind, the sensory receptor within that canal is bent. The receptor then sends impulses to the brain about movement.
When the vestibular apparatus on both sides of the head are functioning properly, they send symmetrical impulses to the brain. That is, the impulses coming from the right side conform to [agree with] the impulses coming from the left side.
http://www.vestibular.org/vestibular...sory-input.php
The eustachian tube has three functions: ventilation, drainage, and protection. When the eustachian tube is patent it allows ventilation of the middle ear and equalization of middle ear and atmospheric pressure. It also allows the middle ear to clear unwanted secretions. By staying physiologically obstructed, it protects the middle ear from nasopharyngeal secretions and sound.
http://www.bcm.edu/oto/grand/71196.html