Hearing and Hearing Loss
The human ear is a precisely tuned system with a sensitivity and range that easily outperforms the most elaborate sound system ever manufactured. The ear contains many physiological mechanisms and a breakdown or disruption in any of these can cause hearing difficulties. In general, there are two main types of hearing loss. Learn more about them here:

Conductive hearing loss
 This type of hearing loss is a condition of the outer and/or middle ear. It occurs when sounds from the outside world cannot be transmitted normally through the ear canal and/or middle ear to the nerve cells of the inner ear. Conductive hearing loss can be temporary or long term. The most common causes of this hearing loss can be a build-up of wax in the ear canal, fluid in the middle ear space (common in children), perforated eardrums, or damaged or defective ossicles (middle ear bones). Most conductive hearing losses can be medically or surgically treated. If the conductive hearing loss for some reason cannot be alleviated, hearing aids can do a lot to compensate for the loss of loudness.

Sensorineural hearing loss
Sensorineural hearing low is the most common form of hearing loss. It happens when some of the delicate hair cells inside the cochlea get damaged and are unable to transform the sound vibrations into electrical signals. Sensorineural hearing loss can be caused by long-term exposure to loud sounds. But the primary reason is the natural process of aging.

Once sensonrineural hearing loss sets in, the condition may continue to worsen and will in most cam be permanent. Typical symptoms we a loss of loudness, and difficulties in understanding speech. Fortunately, advanced hearing technology is avail¬able that can effectively treat sensorineural hearing loss. This technology is used in Delta.

How sounds travel through the ear
The anatomy of the ear is precisely shaped to capture sound waves and amplify them. When sound waves enter the subways of the ear they follow what might seem like a long and arduous path. But every 'station' has a precise function. This is how it works.
1. Sound waves are picked up by the outer ear. which is made up of the pinna and the ear canal.
2. Sound is channeled to the eardrum. which vibrates when the sound waves touch it.
3. The vibrations are picked up by three tiny bones known as the hammer. anvil and stirrup, which create a bridge from the eardrum to the inner ear.
4. The vibrations move on to the cochlea-a spiral-shaped capsule housing a system of liquid-filled tubes.
 5. When the sound waves reach the liquid it begins to move setting thousands of tiny hair cells in motion.
 6. The movements of the hair cells are transformed into electric impulses that travel along the auditory nerve to the brain itself.
7. The brain decodes and interprets the electronic impulses, turning a stream of speech sounds into separate, recognizable words.