Transcript 3.03 Understand the sensory system

3.04 Functions and
disorders of the ear
3.04 Understand the functions and
disorders of the sensory system
1
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
2
Understanding the
functions of the ear:
Hearing
3.04 Understand the functions and
disorders of the sensory system
3
External ear


Pinna: collects sound
waves and sends them to
auditory canal
External auditory canal


Understanding the
functions of the ear
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
4
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
5
Inner ear
Understanding the
functions of the 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
6
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
7
Understanding
the
functions of
the ear
What is occurring at
each structure?
3.04 Understand the functions and
disorders of the sensory system
8
Healthy 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
9
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
10
Disorders of the ear
3.04 Understand the functions and
disorders of the sensory system
11
Disorders of the ear
3.04 Understand the functions and
disorders of the sensory system
12
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
13
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
3.04 Understand the functions and
disorders of the sensory system
14
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
15
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
16
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
17
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
3.04 Understand the functions and
cochlear implants
disorders of the sensory system
18
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
19
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
20
3.04 Functions and
disorders of the ear
The End
3.04 Understand the functions and
disorders of the sensory system
21