1. 3.04 Functions and disorders of the ear
3.04 Understand the functions and disorders of the sensory system

2. 3.04 Understand the functions and disorders of the sensory system
Essential Questions
What are the functions of the sensory system?
What are some disorders of the sensory system?
How are sensory system disorders treated?
How do you relate the body’s communication to the sensory system?
3.04 Understand the functions and disorders of the sensory system

3. Understanding the functions of the ear: Hearing
3.04 Understand the functions and disorders of the sensory system

4. Understanding the functions of the ear
External ear
Pinna: collects sound waves and sends them to auditory canal
External auditory canal
Contains cerumen: protects ear (oily, wax like substance)
Tympanic membrane: separates outer and middle ear
3.04 Understand the functions and disorders of the sensory system

5. Understanding the functions of the ear
Middle ear: cavity in the temporal bone
Ossicles: transmits sounds waves from ear drum to inner ear
1. Hammer: malleus
2. Anvil: incus
3. Stirrups: stapes
Eustachian tube: connects to the pharynx (equalizes pressure in the middle ear with the outside
3.04 Understand the functions and disorders of the sensory system

6. Understanding the functions of the ear
Inner ear
Cochlea: filled with fluid that vibrates when the sound waves from the stirrup bone strike against it
Semicircular canals: liquid and hair like structures bend when set in motion by head and body movements  impulses sent to cerebellum; help maintain balance & equilibrium
3.04 Understand the functions and disorders of the sensory system

7. Understanding the functions of the ear
Pathway of hearing
Trace the pathway of hearing.
Discuss the process of hearing.
What are decibels?
Sound measured in decibels (dB): faintest sound is labeled dB whereas a jet engine is 165dB. Exposure to anything over 90dB for 8 hrs may be dangerous to your hearing.
3.04 Understand the functions and disorders of the sensory system

8. Review the pathway of hearing
Understanding the functions of the ear What is occurring at each structure?
Review the pathway of hearing
3.04 Understand the functions and disorders of the sensory system

9. Healthy Hearing How do you protect your hearing?
Listening to loud noises over a long period of time damage
hair in the organ of Corti (cochlea). It destroys receptors and nerve
cells and the damage is permanent.
How do you protect your hearing?
What is the relevance to healthy hearing?
3.04 Understand the functions and disorders of the sensory system

10. Understanding the functions of the ear
Sound Activity
What is a sound byte?
Short bit of sound or clip from a longer recording.
3.04 Understand the functions and disorders of the sensory system

11. 3.04 Understand the functions and disorders of the sensory system
Disorders of the ear
3.04 Understand the functions and disorders of the sensory system

12. Disorders of the ear What instruments are used to examine the ear?
What specialist studies the ears, nose, and throat?
3.04 Understand the functions and disorders of the sensory system

13. Disorders of the ear External otitis
Discuss what you see in this picture? (Besides a Q-tip!)
What causes external otitis?
How can it be prevented?
3.04 Understand the functions and disorders of the sensory system

14. Disorders of the ear Otitis media What is otitis media?
Ear infection of middle ear
Who is most at risk of having
otitis media? Why?
Children; eustachian tube is shorter so common colds create pressure because of fluid to build up behind the tympanic membrane
What are the treatment options?
Antibiotics or a myringotomy
Normal tympanic membrane
Otitis media
Myringotomy
3.04 Understand the functions and disorders of the sensory system

15. 3.04 Understand the functions and disorders of the sensory system
Disorders of the ear
Otosclerosis
What is it?
Oto- sclerosis
Stapes bone becomes hard making it unmovable. Common cause of hearing loss in young adults.
What causes it?
Inherited disorder
Why is a stapedectomy useful in treating otosclerosis?
Total replacement of the stapes
3.04 Understand the functions and disorders of the sensory system

16. 3.04 Understand the functions and disorders of the sensory system
Disorders of the ear
Meniere’s disease
What are the symptoms of Meniere’s disease?
Vertigo (dizziness)
What causes these symptoms?
Pressure and swelling distorts balance info sent to the cerebellum
How is it treated?
Avoid salt, caffeine, nictoine. Medicines to treat dizziness and nausea. Bedrest and drinking plenty of water.
3.04 Understand the functions and disorders of the sensory system

17. 3.04 Understand the functions and disorders of the sensory system
Disorders of the ear
Tinnitus
What is tinnitus?
Ringing in ears
Explain this statement:
Tinnitus is a symptom, not a disorder.
Sign of hearing loss
3.04 Understand the functions and disorders of the sensory system

18. Disorders of the ear Presbycusis What is presbycusis?
Deafness due to aging
Conductive hearing loss?
Sounds to the inner ear are blocked by wax or fluid in the middle ear or abnormal bone growth
Sensory hearing loss?
Damage to inner ear or auditory nerves; treatment is cochlear implants
What is the difference between
conductive hearing loss and
sensory hearing loss?
How can they be treated?
3.04 Understand the functions and disorders of the sensory system

19. Testing for hearing loss
Rinne test
Weber test
Compare these two tests.
How are they diagnostic?
3.04 Understand the functions and disorders of the sensory system

20. 3.04 Understand the functions and disorders of the sensory system
Essential Questions
What are the functions of the sensory system?
What are some disorders of the sensory system?
How are sensory system disorders treated?
How do you relate the body’s communication to the sensory system?
3.04 Understand the functions and disorders of the sensory system

21. 3.04 Functions and disorders of the ear
The End
3.04 Understand the functions and disorders of the sensory system