Cranial Nerves Flashcards
Cranial nerves of midline
3, 6 and 12
What 2 cranial nn. are not distributed to the head?
Vagus and accessory nn.
Which cranial nn. conduct parasympathetic fibers?
3, 7, 9 and 10
Cranial nerve I
Olfactory
Sensory
Cranial nerve II
Optic
Sensory
Cranial nerve III
Oculomotor
Motor
Cranial nerve IV
Trochlear
Motor
Cranial nerve V
Trigeminal
Both
Cranial nerve VI
Abducens
Motor
Cranial nerve VII
Facial
Both
Cranial nerve VIII
Vestibulocochlear
Sensory
Cranial nerve IX
Glossopharyngeal
Both
Cranial nerve X
Vagus
Both
Cranial nerve XI
Accessory
Motor
Cranial nerve XII
Hypoglossal
Motor
What nerve does not come from the brainstem?
CN I (olfactory) → comes from olfactory bulb
CN I (olfactory) leaves the skull through?
Cribiform plate
Which nerve is technically a tract?
CN II (optic n.)
CN II (optic) connects?
Retina with diencephalon
Vision pathway
- Retina
- Optic n.
- Optic chiasm
- Optic tract
- Lateral geniculate nucleus
- Optic radiation
CN III (oculomotor) arises from?
Ventral aspect of mesencephalon
Where do oculomotor GVE fibers synapse?
Ciliary ganglion
Postganglionic oculomotor GVE fibers
Pass through ciliary nn. to supply ciliary and constrictor pupillae mm.
3 clinical signs of oculomotor n. dysfunction?
- Lateral strabismus
- Ptosis of superior eyelid
- Mydriasis
Strabismus
Abnormal pointing of eye
Ptosis
Drooping
Mydriasis
Dilation of pupil
Pupillary light reflex pathway
- Retina
- Optic n.
- Optic chiasm
- Optic tract
- Pretectal nuclei
- Parasympathetic nucleus of CN III
- Ciliary ganglion
CN IV (trochlear) arises from/
Dorsal aspect of mesencephalon
Clinical signs of CN IV (trochlear) dysfunction
Extorsion of eye
CN V (trigeminal) arises from?
Metencephalon
Mandibular n. function
- Sensory to inferior arcade, lip, tongue
2. Motor to mm. of mastication (except cd. belly of digastricus)
CN VI (abducens) arises from?
Myelencephalon
Clinical signs of CN VI (abducens) dysfunction
Medial strabismus
CN VII (facial) arises from?
Myencephalon
How does VII (facial) give taste sensation to the rostral 2/3 of the tongue?
Via chorda tympani communication with lingual n.
Parasympathetic fibers of CN VII (facial) go to
- Lacrimal gland
- Nasal gland
- Palatine gland
- Mandibular salivary gland
- Sublingual salivary gland
GVE fibers of CN VII (facial) go to the lacrimal, nasal and palatine glands via?
Pterygopalatine ganglion
Only cranial nerve to originate from dorsal aspect of brain?
CN IV (trochlear)
CN VIII (vestibulocochlear) arises from?
Myelencephalon near facial n.
CN IX (glossopharyngeal) arises from?
Lateral aspect of myencephalon
GVE fibers of CN IX (glossopharyngeal) supply?
Parotid and zygomatic salivary glands
Vagus n. arises from?
Lateral aspect of myelencephalon (in line with glossopharyngeal n.)
2 sensory ganglia associated with vagus n.
- Proximal ganglion
2. Distal ganglion
What vagus fibers synapse at the cr. cervical ganglion?
Sympathetic
What vagus fibers synapse at the distal ganglion?
Parasympathetic
Proximal ganglion location
Jugular foramen (cannot be seen)
Distal ganglion location
Caudal to the cr. cervical ganglion
CN IX - XI exits cranial cavity via _____ and emerges from skull via _____
Jugular foramen, tympano-occipital fissure