Cranial Nerves Flashcards
What innervates the cricothyroid?
the VAGUS nerve (10)–> GSE
What are the three branches of the external carotid by the Hyoid Bone?
- Superior Thyroid
- Lingual
- Facial Artery
What branch of the Common Carotid provides blood supply to the brain?
INTERNAL Carotid
What branch of the Facial Nerve (VII) supplies motor function to the PLATYSMA?
Cervical Branch
What is the Sella Turcica? What rests on top of it? What is the result of a tumor in this structure?
The Hypopheseal Plate
- Pituitary Gland
- -> tumor in Pituitary gland causes a disruption in Optic CHIASM = loss of vision
What Cranial Nerves have GVE (parasympathetic) function?
3,7,9,10
What Cranial Nerves have SVE (motor to pharyngeal muscles) function?
5 , 7, 9 , 10
What CN pass through the superior orbital fissure?
3,4,V1, 6
What happens during parasympathetic function?
Slowing the heart (10) Increasing digestion (10) Dropping blood pressure (10) CONSTRICT the pupil (3) ROUNDING up the lens (accommodation) for reading (3) Maintaining erection --> point and shoot* Increasing saliva production (7 + 9) Increasing tear production (7) Increasing nasal secretions (7) Enhancing peeing and pooping (10)
Cows Poop on Shoes
Ciliary (3), Pterygopalatine (7), Otic (9), Submandibular Ganglion (7)
Why is the Trochlear Nerve (4) unique?
- Only one to exit on Dorsal Surface of Brain
- Longest Intracranial course
- Smallest Number of Axons
- Only nerve in which all lower motor neuron fibers decussate (cross to form X) (since in the lower part of Superior Orbital fissure)
INNERVATES THE SUPERIOR OBLIQUE (the muscle that changes direction, sits across the eye)
IO UO, SO DO
Inferior Oblique = Up and Out
Superior Oblique = Down and Out
What does V3 innervate? What functional component is it?
GSA + SVE
ALL FROM 1st PHARYNGEAL ARCH
SVE = motor component
- Muscles of Mastication
1a. Temporalis (close mouth)
1b. Masseter (close mouth)
1c. Medial Pterygoid (close mouth)
1d. Lateral Pterygoid (open mouth) - Mylohyoid (keep tongue in mouth)
- Ant. belly of Digastric
- Tensor Veli Palatini (tenses soft palate)
- Tensor Tympani (dampens sound in ear)
Superior Alveolar nerve terminates as what nerve? Inferior Alveolar?
- Infraorbital
2. Mental
What nerves provide sensory innervation from the Mandibular subdivision of the Trigeminal Nerve?
- Lingual –> sensation to the tongue ANTERIOR 2/3
- Inferior Alveolar (pops out as Mental n.–> innervates lower teeth + skin on chin)
- Buccal –> SENSORY inside the cheek
Superior Alveolar and Infraorbital Nerves are branches of_____ of the TRIGEMINAl
V2 - Maxillary
inferior alveolar (mental), lingual, buccal, and Auriculotemporal = v3 MANDIBULAR
Pablo was running. Doctors repair his punctured aorta but he still has difficult talking after 6 weeks. He leaves the hospital and is killed by a speeding car. Why did he have difficulty speaking?
Damaged X = goes by reccurent pharangeal branch
Name the Nerve:
- To See:
- To Focus:
- When looking at Bright Light:
- To Open your eyes
- When you Force your eyes Closed?
- II
- III (Cilliary Muscle –> accomodate lens)
- III (sphincter Pupillae)
- III (levator Palpebrae)
- VII (7)–> Orbicularis Oculi
What hitches a ride with the lingual nerve of 5 to bring taste to the anterior 2/3 of the tongue?
CHORDA TYMPANI (7)
(Cut the chorda you can’t taste your moms lasagna with the anterior 2/3 of tongue)
* LINGUAL is carrying pain sensation**
What hitches a ride with 5 to cause your eyes to water and nose to run?
CN 7 –> travels on ZYGOMATIC branch of 5 to reach the lacrimal gland via post-synaptic fibers
What muscles originate from the 2nd Pharyngeal Arch?
SVE: Muscles of Facial Expression 1. Posterior Auricular Branch 2. Temporal Branch 3. Zygomatic Branch 4. Buccal Branch 5. Mandibular Branch 6. Cervical Branch also: 7. Posterior Belly Digastric 8. Stylohyoid 9. Stapedius (ear damper) 10. PLATYSMA = 7
Describe the parasympathetic function of 7? (GVE)
GVE: Parasympathetics via:
- Greater Petrosal Nerve –> Pterygopalatine Ganglion –> Lacrimal Gland
- Chorda Tympani –> Submandibular Ganglion –> Submandibular, Sublingual Salivary Glands
Describe the GVA, SVA, GSA, and SVE function of 7
GVA = sensaton to deep palate SVA = taste anterior 2/3 (chorda tympani!) GSA = small part of ear pinna** SVE = Pharyngeal motor = muscles of facial expression + post. belly digastric, platysma, stapedius, stylohyoi, Posterior Auricular branch
Bell’s Palsy is due to a lesion in which nerve? What are some symptoms? What is the cause?
- Lesion in Facial Canal, somewhere between Greater Petrosial Nerve and Chorda Tympani
- No taste, mouth is DRY, but CAN cry
- CAUSE = VIRAL INFECTION
Describe 9 to sense, and 10 to act
9 has GVA function in the Carotid Sinus that recognizes when BP is high–> sends a signal to 10 (VAGUS) to slow down the heart and decrease BP
Describe the functional components of 9
GVA - sensory to deep palate, inner ear, CAROTID sinus, pharynx
SVA- taste posterior 1/3 of tongue ( 7 was anterior 2/3 = chord tympani)
GVE - GLOAP - lesser petrosal, otic ganglion, travels with auriculotemporal nerve of 5, to go to PAROTID DUCT
GSA - sensation to ear pinnae
SVE- stylopharyngeus muscle (aids in swallowing)
What is the function of the stylopharyngeus muscle?
raises larynx + pharynx + AID IN SWALLOWING
- originates from styloid, goes to pharynx
What is the order of muscles originating from styloid process?
- Stylopharyngeus (CN 9), 2. post. belly of digastric (7)
3. Stylohyoid (7)
What originates from the THIRD Pharyngeal arch?
GLOAP
Glossopharyngeul–> lesser petrosal–> otic ganglion –> auriculotemporal –> parotid gland
Describe the functional components of CN X
GVA - sensation to pharynx, larynx, abdominal viscera,
SVA - taste buds to epiglottis and glottis
GVE - PARASYMPATHETIC -> slows digestion, decrease heart rate
GSA - sensation to ear pinnae
SVE - Cricothyroid - tighten vocal chords/talking!! + Levator Palatini + PALATOGLOSSUS
What is the function of cricothyroid?
Speaking -> moving the vocal chords
What controls the muscles of the pharynx and voice box?
CRANIAL NERVE 10 - SVE functional component
What Pharyngeal Arches does CN nerve 10 derive from?
ARCH 4: All CN X muscles above, except intrinsic larynx
ARCH 6: All intrinsic larynx, except cricothyroid (Arch 4)
Eye pointing down and out, Ptosis, and drooping eyelid would be a result of a Palsy in which Cranial Nerve?
Cranial Nerve 3 - Occulomotor
If eye does not abduct would be a result of a Palsy in which Cranial Nerve?
Cranial Nerve 6* ABDUCENS (lateral rectus –> moves eye out)
Bells Palsy
Cranial Nerve 7
** viral infection that can screw up 7 as it passes through the STYLOMASTOID foramen **
