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

2 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?

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

Understanding the functions of the ear External ear Pinna-collects sound waves Pinna-collects sound waves External auditory canal External auditory canal  Contains cerumen-ear wax that protects the ear Tympanic membrane- transmits soundwaves to the ossicles Tympanic membrane- transmits soundwaves to the ossicles 3.04 Understand the functions and disorders of the sensory system 4

Understanding the functions of the ear *Middle ear *Ossicles-3 tiny bones malleus, incus and stapes that transmit sound waves from the ear drum to the inner ear. *Ossicles-3 tiny bones malleus, incus and stapes that transmit sound waves from the ear drum to the inner ear. Eustachian tube- equilizes air pressure in the middle ear. Eustachian tube- equilizes air pressure in the middle ear Understand the functions and disorders of the sensory system 5

Understanding the functions of the ear Inner ear Cochlea-contains the organ of Corti that transmits vibrations to the hearing center of the brain. Cochlea-contains the organ of Corti that transmits vibrations to the hearing center of the brain. Semicircular canals- contain a liquid that sends messages to cerebellum to maintain balance/equilibrium. Semicircular canals- contain a liquid that sends messages to cerebellum to maintain balance/equilibrium Understand the functions and disorders of the sensory system 6

Understanding the functions of the ear Pathway of hearing Sound waves---pinna--- auditory canal---typmanic membrane---ossicles--- stimulate cochlea---cochlea nerve---temporal lobe for interpretation Sound waves---pinna--- auditory canal---typmanic membrane---ossicles--- stimulate cochlea---cochlea nerve---temporal lobe for interpretation What are decibels? What are decibels? The measurement of sound 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 Review the pathway of hearing

Healthy Hearing 3.04 Understand the functions and disorders of the sensory system 9 How do you protect your hearing? What is the relevance to healthy hearing?

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

Disorders of the ear 3.04 Understand the functions and disorders of the sensory system 11 Otoscope-lighted instrument to view the ear Otolaryngologist-specialist of the ear and throat

Disorders of the ear 3.04 Understand the functions and disorders of the sensory system 12

Disorders of the ear External otitis-inflammation of the ear canal 3.04 Understand the functions and disorders of the sensory system 13 Discuss what you see in this picture? (Besides a Q-tip!) What causes external otitis? Bacterial infection due to excessive water exposure, use of q-tips How can it be prevented? Proper ear care, avoid water

Disorders of the ear *Otitis media-infection of the middle ear Who is most at risk of having Who is most at risk of having otitis media? *Most common in children due to a short eustachian tube; often a complication of the common cold *Symptoms: earache, pain, fever, drainage of fluid from the ear What are the treatment options? What are the treatment options? Antibiotics, myringotomy (an opening put in the tympanic membrane), tubes in the ear 14

Disorders of the ear Otosclerosis-inherited disorder; the stapes bone becomes spongy then hardens What is it? What is it?  Oto- sclerosis Why is a stapedectomy useful in treating otosclerosis? Why is a stapedectomy useful in treating otosclerosis? Hearing is re-routed 3.04 Understand the functions and disorders of the sensory system 15

Disorders of the ear Meniere’s disease-the semicircular canals of the inner ear are affected and vertigo (dizziness) occurs What are the symptoms of Meniere’s disease? Vertigo, nausea, vomiting, tinnitus (ringing in the ears) What are the symptoms of Meniere’s disease? Vertigo, nausea, vomiting, tinnitus (ringing in the ears) What causes these symptoms? What causes these symptoms? How is it treated? Bedrest, medication, avoid salt, caffeine, nicotine, eat a balanced diet, plenty of H2O How is it treated? Bedrest, medication, avoid salt, caffeine, nicotine, eat a balanced diet, plenty of H2O 16

Disorders of the ear *Tinnitus-ringing in the ears What is tinnitus? What is tinnitus? Explain this statement: Tinnitus is a symptom, not a disorder. *May be caused by impacted wax, otitis media, otosclerosis, blockage of blood supply to the cochlea, loud noises 3.04 Understand the functions and disorders of the sensory system 17

Disorders of the ear Presbycusis What is presbycusis? What is presbycusis? Deafness due to aging Who is most likely to develop presbycusis? Who is most likely to develop presbycusis? 3.04 Understand the functions and disorders of the sensory system 18

Disorders of the ear *Conductive hearing loss is due to wax or fluid build up that blocks sound to the inner ear. Sensory hearing loss is caused by damage to parts of the inner ear or auditory nerve Understand the functions and disorders of the sensory system 19

Testing for hearing loss 3.04 Understand the functions and disorders of the sensory system 20 Weber test Rinne test Compare these two tests. How are they diagnostic?

3.04 Understand the functions and disorders of the sensory system 21 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 Functions and disorders of the ear The End 3.04 Understand the functions and disorders of the sensory system 22