The ear is an organ specialized for hearing and balance. It is also a part of the upper respiratory tract, connected via the eustachian tube to the back of the nose. This fact is important in understanding why the ear may become infected, for example, as a result of a cold or nose or throat infection.

The Structure of the Ear
Think of the ear as being made up of three parts , the middle ear, and the inner ear:

• The outer ear is made up of the visible part of the ear (the auricle) and the ear canal, which is lined with thin skin
• The middle ear is made up of the ear drum (tympanic membrane) and three small bones of hearing (ossicles). These three small bones are named the malleus (hammer), the incus (anvil), and the stapes (stirrup), and they help carry sound inward
• The inner ear is made up of the cochlea or hearing organ, and the balance canals.

How We Hear
Sound is energy carried in the vibration of air molecules. Normally, those vibrations are captured by the ear drum. The ear drum is attached to the three small bones of hearing. The ear drum and the three small bones all vibrate together, and help carry the sound inward, toward the inner ear.

In the inner ear, fine nerve endings capture these vibrations and carry them up to the brain, where they are perceived as sound.

What Is Hearing Loss?
Hearing loss is more than just a sound barrier - it can negatively impact the quality of life and cause a sense of complete isolation for those who suffer from it. There are approximately 24 million people in the United States who have a significant loss of hearing. Fortunately, there are mechanisms that can improve hearing - people with hearing loss do not have to feel alone.

Causes of Hearing Loss
There can be many causes of hearing loss. Among the most common are:

• Ear infections
• Certain medications can cause hearing loss - some are reversible and some are irreversible. For instance, high doses of aspirin can cause hearing loss but the effect is reversed when the dose is reduced or discontinued. Certain chemotherapy agents, for instance, Cis-platinum, can cause irreversible hearing loss.
• Excessive noise exposure
• Heredity
• Birth defects
• Traumatic injury (such as a head injury)
• Tumors
• The natural aging process. About 30 percent of people over the age of 60 have hearing loss. It is the third most common chronic problem affecting the aging population.

Symptoms of Hearing Loss
Hearing loss is often difficult to recognize. It is usually easiest to tell if you have a hearing loss if you are doing one or more of the following:

• Continually turning up the volume on your TV
• Having difficulty hearing conversational speech
• Having difficulty hearing in group situations and when there is background noise (i.e. in a restaurant)
• Asking people to repeat themselves often
• Speech might not sound clear. You might think that other people are mumbling

Hearing, Facial Nerves and Balance Disorders at Mount Sinai
There is a rich history of treating Hearing, Facial Nerves and Balance Disorders (otology and neuro-otology) at Mount Sinai. Dr. Samuel Rosen was a pioneer in otology, particularly noted for stapes mobilization for otosclerosis during the early 1950s.

Today, Mount Sinai provides treatment for a broad range of adult and pediatric otologic and neuro-otologic disorders. The multidisciplinary team of physicians and allied health care professionals include representation by experts in otology, neuro-otology, and cranial base surgery; neurosurgery, neurology; geriatric medicine; opthalmology; rehabilitative medicine; clinical neurophysiology; audiology; physical therapy; speech pathology; psychology and psychiatry, and neuroradiology.