Ménière's disease the inner ear. The American Academy of Otolaryngology–Head and Neck Surgery Committee on Hearing and Equilibrium (AAO HNS CHE) set criteria for diagnosing Ménière's, as well as defining two sub-categories of Ménière's: cochlear (without vertigo) and vestibular (without deafness). In 1972, the Academy defined criteria for diagnosing Ménière's disease as: In 1985, this list changed to alter wording, such as changing "deafness" to "hearing loss associated with tinnitus, characteristically of low frequencies" and requiring more than one attack of vertigo to diagnose. Finally in 1995, the list was again altered to allow for degrees of the disease: In 2015, the
Inner ear between 20 and 20,000 Hz. The ability to detect higher pitch sounds decreases in older humans. The human ear has evolved with two basic tools to encode sound waves; each are separate in detecting high and low frequency sounds. Georg von Békésy (1899-1972) employed the use of a microscope in order to examine the basilar membrane located within the inner-ear of cadavers. He found that movement of the basilar membrane resembles that of a traveling wave; the shape of which varies based on the frequency of the pitch. In low frequency sounds, the tip (apex) of the membrane moves the