The Human Ear
Outer Ear
pinna
ear canal
1. The outer ear collects and
amplifies sound waves.
PINNA
(outer, flappy part)
EAR CANAL
OUTER EAR PARTS
The pinna collects the sound waves (vibrations) and funnels
them into the ear canal, where they are amplified.
WHAT HAPPENS HERE?
Middle Ear
ear drum hammer anvil
stirrup
1. The outer ear collects and amplifies sound waves.
2. The sound waves make the ear drum vibrate.
http://www.youtube.c om/watch?v=mG64SfveT lU
1. The outer ear collects and amplifies sound waves.
2. The sound waves make the ear drum vibrate.
3. The eardrum causes 3 tiny
bones to vibrate. (hammer, anvil, stirrup)
EAR DRUM
HAMMER
ANVIL
STIRRUP
MIDDLE EAR PARTS
3 tiny bones
Sound waves vibrate the ear
drum, which causes the 3 bones of the middle ear to vibrate.
These bones act as levers to increase the vibrations.
WHAT HAPPENS HERE?
Inner Ear
cochlea
1. The outer ear collects and amplifies sound waves.
2. The sound waves make the ear drum vibrate.
3. The eardrum causes 3 tiny bones to vibrate. (hammer, anvil, stirrup)
4.
The tiny bones make the fluid in the cochlea vibrate.1. The outer ear collects and amplifies sound waves.
2. The sound waves make the ear drum vibrate.
3. The eardrum causes 3 tiny bones to vibrate. (hammer, anvil, stirrup)
4. The tiny bones make the fluid in the cochlea vibrate.
5. This causes tiny hair cells to vibrate (in cochlea)
Remember how older people have a harder time hearing high frequency sounds??
This is why!! The hair cells detecting higher frequency sounds are getting the most
damage because they are where the sound waves first hit!
1. The outer ear collects and amplifies sound waves.
2. The sound waves make the ear drum vibrate.
3. The eardrum causes 3 tiny bones to vibrate.
(hammer, anvil, stirrup)
4. The tiny bones make the fluid in the cochlea vibrate.
5. This causes tiny hair cells to vibrate (in cochlea)
6. Vibrations are passed to the auditory nerve which leads to the brain.
auditory nerve
1. The outer ear collects and amplifies sound waves.
2. The sound waves make the ear drum vibrate.
3. The eardrum causes 3 tiny bones to vibrate.
(hammer, anvil, stirrup)
4. The tiny bones make the fluid in the cochlea vibrate.
5. This causes tiny hair cells to vibrate (in cochlea)
6. Vibrations are passed to the auditory nerve which leads to the brain.
7. The brain interprets
sound!
The brain interprets sound!
The stirrup then vibrates against the cochlea, which is filled with fluid.
The tiny hairs in the cochlea send electrical signals to the auditory nerve and on to the brain.
WHAT HAPPENS HERE?
Main Purpose
How the Ear Works
1. “How the Ear Works” (3:25)
http://www.youtube.com/watch?v=qgdqp-oPb1Q 2. “How Your Ear Works” (1:42)
http://www.youtube.com/watch?v=r-c5GpoD8wI
Hearing Loss
1. Ear Buds and Hearing Loss (2 minutes)
2. 1.1 Billion at Risk of Hearing Loss (3 min) 3. Musical Savants video (15 minutes)
Summarizer
!
OUTER EAR MIDDLE EAR INNER EAR
pinna
ear drum ear canal
hammer
anvil
stirrup
auditory nerve
cochlea
Hearing Loss:
Types
Conductive hearing loss - when hearing loss is due to problems with the ear canal, ear drum, or middle ear and its little bones
(hammer, anvil, stirrup).
Sensorineural
hearing loss (SNHL) - when
hearing loss is due to problems of the inner ear, also known as
nerve-related hearing loss.
Mixed hearing loss - refers to a combination of conductive and
sensorineural hearing loss. This means that there may be damage in the outer or middle ear and in the inner ear (cochlea) or auditory nerve.
Hearing Loss:
Causes
Damage to the inner ear.
Aging and prolonged exposure to loud noise may cause damage to the hairs or nerve cells in the cochlea that send sound signals to the brain.
When these hairs or nerve cells are damaged or missing, electrical signals aren't transmitted as efficiently, and hearing loss occurs.
Higher pitched tones may become muffled.
A gradual buildup of earwax.
Earwax buildup or an object in the ear. This is common and easily
treated.
Ruptured eardrum.
Loud blasts of noise, sudden changes in pressure, poking your eardrum with an object and infection can cause your eardrum to rupture and affect your
hearing.
Be careful when cleaning your ears with Q-Tips!
You could puncture your eardrum if you are not careful
http://www.youtube.com/watch?v=mG64SfveTlU
Hearing Loss: Medicine
Certain antibiotics and other
substances (such as arsenic, mercury, tin, lead, and manganese) can damage the ear.
Hearing Loss: Injury
Injury to the ear or head. Head
injuries can also damage the structures in the ear and cause a sudden hearing loss.
Hearing Loss: Ear Infection
Ear infection, such as a middle ear
infection (otitis media) or an infection of the ear canal (otitis externa or
swimmer's ear).
Hearing Loss: Fluid
Fluid in the middle ear after a cold or the flu, or after traveling on an airplane.
Hearing Loss: Others
Otosclerosis, a condition that affects the bones of the middle ear.
Acoustic neuroma, a noncancerous tumor on the nerve that helps people hear.
Ménière's disease. Ménière's disease may
result in temporary or permanent hearing loss.
Noncancerous (benign) growths
There are many, many, many more!
Hearing Loss: Causes and Treatment
1. Mother hears 8-year old son's voice for the first time on The Doctors (2:50) (Cochlear Implant/ Qualms about receiving one)
http://www.youtube.com/watch?v=m8VV7oxvQ_g
3. Deaf baby hears for the first time (00:49) (cochlear implant) http://www.dump.com/deafbaby/
4. “Miracle Baby” (3:13) (Implant directly to the brain stem) http://www.youtube.com/watch?v=-GA9gEh1fLs
5. “Cochlear Implants” (What a cochlear implant sounds like) (3:06)
http://app.discoveryeducation.com/player/view/assetGuid/D7E817D9-D0A9-4A7E -B6C6-20C9B5C39F71##
Hearing Loss: Causes and Treatment (additional)
1. “Understanding Hearing Loss” (7:39)
http://www.youtube.com/watch?v=QF2aDZu7IEs
2. “Hearing, But Not As You Know It” (9:19)
http://www.youtube.com/watch?v=icPsm9RnO2E