Test 4 Cranial Nerves: MB

How many pairs of cranial nerves are there?
CN #1
Which cranial nerve is the highest?
Are cranial nerves part of the CNS or PNS?
(they are similar to spinal nerves)
Are cranial nerves visible by the naked eye?
Yes, they are big-sometimes can see ________ on them
Cranial nerves
2. Optic
3. Oculomotor
4. Trochlear
5. Trigeminal (ophthalmic, maxillary, and mandibular divisions)
6. Abducens
7. Facial
8. Vestibuloacoustic
9. Glossopharyngeal
11. Spinal accessory
12. Hypoglossal

O O O to touch and feel a girls very soft hands
oculomotor, Trochlear, Abducens
Which cranial nerves control the movement of the eye?
speech, language, and hearing
Which cranial nerves are important for _________ _________ _____ _____________?
#11-Spinal accessory
How many cranial nerves are important for speech, language, and hearing?
What is the function and way of testing CN I: olfactory
How to test- use an odorous substance
What is the function and way of testing CN II: optic
How to test-vision chart
eye movements
What is the function and way of testing CN III: oculomotor
Function-most _____ ___________
How to test-"following the moving finger"
superior oblique
What is the function and way of testing CN IV: trochlear
Function-__________ __________
How to test-look down at nose
facial sensation and muscles of mastication
What is the function and way of testing CN V: Trigeminal
Function-___________ __________ _________ ____________ _____ _________________
How to test-touch the face and clench the teeth
lateral rectus
What is the function and way of testing CN VI
Function-__________ ______
How to test-look to the side
Facial expression and taste
What is the function and way of testing CN VII
Function-_________ __________ ______ _______
How to test-smile, raise the eyebrows and sugar or salt
hearing and balance
What is the function and way of testing CN VIII: Vestibuloacoustic
Function-_____________ _____ _________
How to test- a tuning fork and look for vertigo
pharynx sensation
what is the function and way of testing CN IX: Glossopharyngeal
Function-__________ _________
How to test-gag reflex
larynx and pharynx
What is the function and way of testing CN X: Vagus
Function-muscles of the __________ ______ _________ parasymp.
How to test- check for hoarseness, open wide and say "AH"
trapezius and sternocleidomastoid
What is the function and way of testing CN XI
Function-____________ ______ _________________________
How to test-test shoulder raise or turning the head
tongue muscles
What is the function and way of testing CN XII
Function-_________ ____________
How to test-stick out the tongue
(CN #1) Olfactory Nerve
*Originates at the level of telencephalon (forebrain)
*Pure sensory nerves which originate from the nasal mucosa part of the nerve and travel to the olfactory bulb at the inferior portion of the frontal lobe
*Damage to this nerve causes anosmia
Inability to smell
olfaction and taste
What two senses have chemical sense?
olfaction, species
The sense of _______________ is more powerful in other _________________.
Who has a better sense of smell males or females?
(CN #2) optic nerve
*Originates at the level of diencephalon(forebrain)
*95% sensory (afferent) nerves
*5% efferent which change the size of pupils
Course of the nerve-starts from nasal and temporal fibers that originate from the retina and continue their course toward the optic chiasm to the optic tract, then towards LGB of thalamas, finally makes a loop (Myer's loop) amd terminates at Brodmann's area #17 in the Occipital Lobe
(CN#3) Oculomotor
*Originates at mesencephalon (midbrain)
*Pure motor nerve
*Involved in movement of the eye, regulation of pupil size, and convergence of the eyes
*Innervates 5 eye muscles
*damage can result in disconvergence(poor convergence of the eyes-lazy eye)
Convergence of the eye
when the eyes come together
(CN #4) Trochlear
*Originates at mesencephalon (midbrain)
*Pure motor nerve
*Innervates only a single eye muscle-called superior oblique muscle
*damage can cause poor eye movement
Superior Oblique Muscle
Which eye muscle does CN IV Trochlear innervate?
(CN #5) Trigeminal Nerve
*Originates at the level of Pons
*Innervates a muscle of the middle ear-tensor tympani
*Made of three divisions or branches (Ophthalmic V1, Maxillary V2, and Mandibular V3)
*Has mixed nerves (senory and motor)
*Provides motor fibers to muscles of mastication
*Has sensory fibers that provide sensory information for facial, orbital, and oral areas (teeth, oral cavity, and mouth)
*Damages can cause paralysis, difficulty with chewing, and numbness of the face
Opthalmic, Maxillary, Mandibular
What are the 3 branches of CN #5? Trigeminal
_____________ V1, _________ V2, and ___________ V3
temporalis, massetter, and the external pterygoid
What are the muscles of mastication that receive motor fibers from CN #5? Trigeminal nerve
(CN V) Trigeminal
Which CN has the most width and is the biggest?
pain from the nerve
Trigeminal Neurolgia
Results from damage to CN V-lack of sensory or motor function
*feel pain while brushing teeth or shaving face
(CN #6) Abducens Nerve
*Originates at level of Pons
*Pure motor nerve
*Innervates fibers to only one muscle called lateral rectus muscle
*damage can cause double vision
Convergent Strabismus
double vision
treatable condition with physical eye therapy or surgery
(CN #7) Facial Nerve
*mixed nerve(mainly motor though)
*Innervates muscles of facial expression (smiling, orbic pallaris, and oris)
*Sends branches to (innervates) glands that generate saliva and tears (salvia glands and lacrimal glands)
*sends motor nerves to the stapedius muscle in the middle ear which is important for acoustic reflex
*the sensory branch is called Cortid Tympani-it passes through the middle ear behind the tympanic membrane-innervates anterior 2/3 of the tongue for sense of gustation(taste)
*Damage can cause Bellis, facial paralysis, increased sensitivity to sound called hyperacusis, and lack of sense of taste
Increased sensitivity to sound
What are the 5 branches in the 7th cranial nerve that go from the foramen- stylomastoid to the neck, face, and other areas around the eye?
(CN #8) Vestibuloacoustic Nerve
*Originates at the level of Pons
*Mainly a sensory nerve (more than 90% afferent)-however some are efferent fibers which innervate OHC of the cochlea
*the efferent fibers are called-Olivo Cochlear Bundle
*Has two major branches-vestibular and cochlear
*Damage can cause vertigo, deafness, hearing loss, imbalance, abnormal nystagmus
Vestibular schwannoma
Acoustic neuroma
What are the tumors called that can be caused by damage to CN #8?
Facial nerve decompression
What will remove the tumors caused by damage to CN #8 __________ ________ ______________ which may lead to paralysis
(CN #9) Glossopharyngeal Nerve
*also called Jacobson's Nerve
*Originates at the level of medulla
*Mixed nerve
*Involved in process of swallowing
*Innervates posterior 1/3 of tongue
*Responsible for gag reflex
*damage can cause loss of taste and attribution to swallowing
(CN #10) Vagus Nerve
*Originates at the level of medulla
*Mixed nerve-mainly motor
*sensory branches give sense of taste for the posterior areas of the throat
*Provides sensory information from the thoracic and abdominal areas
*Elevates the palate
*associated with phonation and swallowing
*damages to this nerve can cause dysphonia or swallowing disorders
lack of voice
Arnold Nerve
makes you cough when you put an eartip in your ear b/c it stimulates CN #8
very sensitive to vagus nerve-person becomes faint and may die b/c gives a virus to the heart
Vagal Nerve stimulation
Use electrical pulse or stimulation-results in reduction of tinnitus in rats
(CN #11) Accessory Spinal Nerve
*Originates at level of medulla
*Mainly motor nerve
*Innervates sternocleidomastoidian muscle and trapezious muscle
* Has two branches-spinal and cranial
*damage can result in paralysis of sternocleidomastoidian muscle and trapezious muscle-which will influence normal speech
(CN #12) Hypoglossal Nerve
(under the tongue nerve)
*originates at the level of medulla
*Mainly motor nerve
*innnervates extrinsic and intrinsic muscles of the tongue
*controls movement of the tongue
*damage can result in hemiparalysis of the tongue(half of the tongue can't move)