In traditional Chinese medicine (TCM), the ears are considered to be the openings of the kidney on the body surface. It is no surprise then that hearing relies on nourishment from essence stored in the kidneys. A famous TCM classic Yilin Gaicuo (Errors Corrected from the Forest of Physicians) published in 1830 said, "The two ears communicate with the brain, and all the sound they perceived will be conveyed to the brain." When kidney essence is transformed into the marrow, part of the marrow collects to form the "sea of marrow" which makes up the brain and spinal column, which are responsible for neurological functions as well as intelligence. If the kidney essence is abundant then so will be the sea of marrow resulting in acute hearing. However, if there is inadequate kidney essence to nourish the sea of marrow then hearing disorders like Tinnitus (ringing in the ears) or deafness appear. In the elderly, increasing deafness coincides with the age-related depletion of kidney essence