1. How you Hear Sound Ch.2, Sect. 4 Notes

2. The Human Ear
The function of your ear is to gather ___SOUND__ waves and send, or transmit, information to your ___BRAIN___.
The outer ear __FUNNELS__ sound waves, the middle ear __TRANSMITS____ the waves inward, and the inner ear ___CONVERTS___ sound waves into a form that travels to your ___BRAIN__.
BrainPop- Hearing (3:15)

3. Outer Ear
The outermost part of your outer ear looks and acts like a __FUNNEL___.
Sound waves is collected and directed to a narrow region call the ___EAR CANAL_____.
The ___EARDRUM___ is a small, tightly stretched, drum like membrane.
Sound waves make your eardrum __VIBRATE__.

4. Middle Ear
The middle ear contains the 3 ___SMALLEST____ bones in your body – the __HAMMER___, the _ANVIL__, and the ____STIRRUP_____.
The hammer is attached to the ___EARDRUM____.
After the hammer vibrates the transmission is sent to the ___ANVIL___ and then to the ___STIRRUP___.

5. Inner Ear
The __COCHLEA__ is a fluid-filled cavity shaped like a ___SNAIL SHELL____.
There are more than 10,000 tiny structures inside the cochlea called ____HAIR CELLS___.
The hair cells move, causing ___MESSAGES___ to be sent to the brain through the ____AUDITORY NERVE____.
The brain processes these messages and __TELLS__ you what you heard.
BrainPop- Balance (3:23)

6. Hearing Loss
A person may have difficulty hearing __SOFT_ sounds or __HIGH-PITCHED__ sounds.
There are many causes of hearing loss, including __INJURY__, __INFECTION_, ___EXPOSURE__ to loud sounds, and __AGING__.

7. Causes of Hearing Loss
Hearing loss can happen __SUDDENLY__ if the eardrum is ___DAMAGED____ or ___PUNCTURED____.
It is ___DANGEROUS___ to put objects into your ear.
__INFECTIONS__ also can damage the delicate inner ear, causing permanent hearing loss.
Extended __EXPOSURE___ to loud sounds can damage hair cells in the ear.
You can __PREVENT___ this type of hearing loss by wearing hearing __PROTECTION__.
The most common type of hearing loss occurs ____GRADUALLY____.
Older people often have difficulty hearing
___HIGH-FREQUENCY___ sounds.

8. Hearing Aids Hearing aids can _RESTORE__ some ability to hear.
Hearing aids ___AMPLIFY___ sounds.
Cochlear Implant YouTube (7:15) - Hyperlinked to picture