Ear

The human ear is the organ responsible for hearing and balance. The ear consists of three parts: the outer, middle, and inner ears. Audition is the scientific name for the sense of sound. Sound is a form of energy that moves through air, water, and other matter, in waves of pressure. Sound is the means of auditory communication, including frog calls, bird songs and spoken language. Although the ear is the vertebrate sense organ that recognizes sound, it is the brain and central nervous system that "hears". Sound waves are perceived by the brain through the firing of nerve cells in the auditory portion of the central nervous system. The ear changes sound pressure waves from the outside world into a signal of nerve impulses sent to the brain.

Tinnitus

Tinnitus is a ringing, swishing, or other type of noise that seems to originate in the ear or head. In many cases it is not a serious problem, but rather a nuisance that eventually resolves. Rarely, however, tinnitus can represent a serious health condition. It is not a single disease, but a symptom of an underlying condition.