hmm.. body balance is controlled by ear (huh?!), specifically the innermost part, the vestibule component.
Vestibule itself contain 3 tubes, 3 ampulles(some bulging part at the end of each tube), & a sac that combine these 3 tubes called utricle..
in each ampulla, there's a small brush-like structures, covered in gel. this structure receive any movement of the 'brush' & convert it to electric impulse to be sent to the brain. on top of the gel is a group of crystals called otolith crystals. Any movement will drag the gel & the crystal toward the direction of movement..
imagine the coyote in the bugs bunny series.. there is a part where he run with his body first, leaving his head still at the place where he stand (making his neck stretch). then after a few second, his head follow his body direction.. this is how otolith crystals works, assuming the crystals is the coyote's head. When the gel is moved to front, for example, at first the crystals still in its initial place. they follow the movement after a microseconds..
(soo much for pranks :p)
could not stop wondering the reason betahistin exist in the case but no such word in most major references.. what i could get is vertigo itself consist of 2 major types; physiology (sea sick, car sick, height sick) & pathology (disturbances in the part itself)
in pathology type, there are several types under this. some that i know is Meniere syndrome (or Meniere disease?!) which characterise by tinnitus (sound in ear, maybe sound like 'ngiiiiiiing'?!). This one mainly because of overproduction of the fluid (called endolymph), causing the space around vestibule component become dense (i understand this today- 01-04-2008).
in this type, the patient is given medicine like promethazine and anti nausea (?). Worse, diazepam is given, but this one cause the patient to go to sleep instead of enable to do everyday work.. this is where the betahistin exist, eventhough the real mechanism is still in debate (?). From what i understand, betahistin has small effect of histamine, that it might provoke asthma in asthma users..
Other is Benign Paroxysm Peripheral Vertigo (BPPV), which characterise by one-sided vertigo when on certain position (easiest to detect during sleep on one side). This type occurs because of some particles otoliths crystal are apart from it's place (usually they float in the posterior tube). This one, when in mild condition, is treated using a group of movements called Epley maneuver. This is done to 'bring back the crystal to it's place' (Is it? I dunno, but almost sound like that.. :p). I also pass through a sentence saying that Meniere disease could be the cause of BPPV
(Reader: what on earth is she writing about?!)
