Hearing loss is delineate by variable degrees, not percentages. deafness could also be delicate, moderate, moderately-severe, severe or profound and vary across pitches. it's determined by a straightforward hearing take a look at because the quantity of volume loss you expertise compared to a mean of the many different adult listeners with traditional sensory system systems.The volume, or intensity, of sounds you hear is measured in decibels , zero sound unit being the softest whisper and a hundred and twenty sound unit being a reaction-propulsion engine. The softest sounds one will hear area unit known as thresholds.Normal hearing thresholds for adults area unit thought of zero to twenty five sound unit.

Hearing Aid:- Hearing aid is a device that is used by the people having the problem of hearing loss. It consist of microphone, loudspeaker, amplifier and a battery. It increases the volume of sound that enters into your ear.



Hearing functionality in brief:

Hearing process done through various step that change sound wave into electrical signal. our auditory nerve carries these signal to brain.

1. Sound waves enter the outer ear after that pass-through a narrow gateway which is called the ear canal, which leads to the eardrum.

2. The eardrum vibrates from the incoming sound waves and sends these vibrations into three tiny bones in middle ear. These bones are called as malleus, incus and stapes.

3. The bones in the middle ear amplify, increase sound of vibration and send them into cochlea, snail shaped structure filled with fluid in the inner ear part. An elastic partition run from starting to the end of cochlea, divided in to upper and lower part. This partition is called the basilar membrane because of it serve as the base/ground floor, on that key hearing sit.

4. When the vibrations cause the fluid inside the cochlea to ripple wave form along the basilar.