1. Sponge: Set up Cornell Notes on pg. 55 Topic: 12
Sponge: Set up Cornell Notes on pg. 55 Topic: 12.6: Middle Ear Essential Questions: The tympanic reflex is a protective mechanism for hearing, what CAN’T it protect against?
12.6: Middle Ear
2.1 Atoms, Ions, and Molecules

2. Middle Ear

3. Our Amazing Hearing (4m32s)
P Take 5 bullets

4. Tympanic cavity air-filled space in temporal bone

5. Middle Ear Auditory ossicles
3 small bones that vibrate in response to ear drum
Transmit vibrations between the tympanic membrane and the inner ear
1. Tympanic membrane vibrates the malleus 
2. Malleus (hammer) vibrates the incus 
3. Incus (anvil) vibrates the stapes 
4. Stapes (stirrup) vibrates against the oval window 
5. Oval window moves fluids in inner ear which stimulate the hearing receptors
Malleus
Stapes
Incus

6. Pg. 54 Incus Malleus Oval window Stapes Tympanic membrane Color code
(Anvil)
Malleus
(Hammer)
Oval window
Stapes
(Stirrup)
Tympanic membrane

7. How the Ear Works (3m25s) P. 54 Take 3-5 bullets

8. Middle Ear
Tympanic reflex is elicited in about 1/10 of a second following a loud external sound
2 small skeletal muscles contract, reducing the effectiveness in transmitting vibrations to the inner ear
Reduces pressure from loud sounds that might otherwise damage the hearing receptors
BUT, it cannot protect hearing receptors from loud sounds which occur rapidly
Ex: explosion, gun shot

9. Auditory Tube Auditory Tube aka Eustachian Tube
Connects middle ear to throat
Allows air to pass between the tympanic cavity and the outside of the body by way of the throat and mouth
Helps maintain equal pressure on both sides of tympanic membrane
Necessary for normal hearing
Usually closed by valve-like flaps in throat

11. Auditory Tube Noticeable during rapid change in altitude
Ex: High to low altitude
Air pressure on outside of tympanic membrane increases
Tympanic membrane is pushed inward, impairing hearing
Air will force its way up into the middle ear
This equalizes the pressure on both sides of the tympanic membrane, moving it back into its rightful position
Causes a “popping” sound
Swallowing, yawning, or chewing aid in the opening of the valves and can hasten equalization of air pressure

12. 12.6: Middle Ear Infections
Sponge: Set up Cornell Notes on pg. 57
Topic:
12.6: Middle Ear Infections
Essential Questions:
What is the major cause of middle ear infections?
What are some complications of ear infections?
12.6: Middle Ear Infections
2.1 Atoms, Ions, and Molecules
What is the major cause of middle ear infections?
What are some complications of ear infections?

13. Otitis Media “Ear Infection”
Otitis Media aka “Middle ear infection”
Fluid builds up in middle ear
Breeding ground for bacteria, which causes infection
The mucous membranes that line the auditory tubes connect with the linings of the middle ear which creates a conduit for bacteria infecting the throat or nasal passages
Greater in young children
Usually treated with antibiotics

14. Pg. 56 Pictures Pictures Pictures Pictures Otitis Media
Symptoms Causes Consequences Treatment
Pictures
Pictures
Pictures
Pictures

15. Symptoms Ear Infection Symptoms
The main warning sign of infection is sharp ear pain.
You may be especially uncomfortable lying down, so you might have a hard time sleeping. Other problems to look for:
Trouble hearing
Fever
Fluid oozing from ears
Dizziness
Stuffy nose

16. Causes
Fluid in the Ear
If the Eustachian (auditory) tube gets blocked, fluid builds up inside middle ear.
This makes the perfect breeding ground for bacteria and viruses, which can cause infections.
Your doctor will look inside your ear with an otoscope, which can blow a puff of air to make his eardrum vibrate. If the eardrum doesn’t vibrate as much as it should, chances are there’s fluid inside.

17. Possible Consequences
1. Bursting an Eardrum
If too much fluid or pressure builds up inside your middle ear, the eardrum can actually burst (shown here).
If that happens, you may see yellow, brown, or white fluid draining from the ear.
Although this sounds scary, the eardrum usually heals itself in a couple of weeks.
Unless it happens a lot, your hearing should be fine. The good news is that the pain may suddenly disappear because the hole lets the pressure go

18. 2. Hearing Loss
If ear infections keep coming back, they can scar his eardrums and lead to hearing loss, speech problems, or even meningitis.
If a person suffers from infections often, they might want to have their hearing tested just in case.

19. Treatment Options Antibiotics
using antibiotics both topical and oral can provide you relief from earache by fighting the infection, as they stop swelling and itching of the ear.

20. Treatment Options
2. Myringotomy- An incision is made in the tympanic membrane
Tympanostomy tubes aka “ear tubes” are Inserted into affected ears during surgery
Form a small tunnel so ears can drain
Tubes usually fall out on their own
Hopefully the child has outgrown the susceptibility to ear infections
*This is only used in cases of chronic ear infections

21. Tympanostomy Tubes 1m 34s

22. Tonsils Can Be the Cause
Sometimes a child’s tonsils get so swollen that they put pressure on the Eustachian tubes connecting her middle ear to her throat -- which then causes infections.
If that keeps happening, the tonsils may have to be taken out

23. Use the video and the “All About Ear Infections” reading to add to your Otitis Media Tree-Map
DON’T forget to add pictures!
I want a FULL Tree-Map

24. Otitis Media Video 4m30s