Cranial Nerves Review Flashcards
CN1 path
axons pass thru cribriform plate of the ethmoid bone
-symapse in mitral cells and pass backwards in the olfactory tract
-end in the primary olfactory cortex whichh is located in the temporal blob
what is the only cranial nerve that does link to thalamus
CN1
What is the path of CNII
Visual impulses sent via the optic nerve which meet at the optic chasm
fibres from the optic tract synapse in the lateral geniculate body of the thalamus and continue as optic radiation to primary visual cortex
what happens if there is damage at optic chasm, optic radiation and primary visual cortex
optic chasm- bitemporal hemianopia
Optic radiation- homonymous hemianopia
Visual cortex- Homonymous hemianopia w macular sparing
what parasympathetic fibres does CNIII carry
to the iris mm via the colliery ganglion from the Edinger-Westphal nucleus (in midbrain)
For constriction of the pupil and lens occomidation
What does CNIV do
sup oblique mm
-turns the eye down and out
What is the only cranial nerve that exits brainstem dorsally
CNIV
where is the motor nucleus of CNV seen and what does it supply `
Pons
-supplies the mm of mastication
where are the three parts of the sensory trigeminal nucleus located and what do they carry
Mesencephalic (carries proprioception)- located in midbrain
Main sensory (carrying touch)- in pons
Spinal (carriying pain + temp) in medulla and extends into the upper cerv segments
What is the pterygopalatine ganglion attached to and what does it inn
attached to maxillary div of CNV
-recieves parasympathetic fibres from sup salivary nucleus of CN7
what does the otic ganglion attach to and what does it inn
attached to auriculotemporal branch of the mandibular div of CNV
recieves parasympathetic fibres from inf salivary nucleus of CNIX
What is the submandibular ganglion attached to and what does it inn
Attached to lingual branch of the ant div of mandibular div
-recieves parasympathetic fibres from sup salivary nucleus via CNVII
what are the 4 nuclei of the facial nerve
motor (motor nucleus in pons)
Ordinary sensation (sensory nucleus of the trigeminal n)
Parasympathetic (sup salivary nucleus)
Taste (solitary tract nucleus)
What are the 5 branches of the facial nerve mm
Ten Zebras Broke My Car
-Temporal
-Zygomatic
-Buccal
-marginal mandibular
-cervical
what other mm does the facial nerve innervate other than facial mm
stylohyoid
post belly of digastric
where does the facial nerve conduct taste from
ant two thirds of the tongue via the nucleus solitarius
where does the facial nerve carry parasympathetic fibres
from sup salivary nucleus to the submandibular and sublingual salivary glands via sub,amdibular ganglion of CV V3
what does the facial nerve carry general sensory afferents from
skin of the external ear canal via the auricular branch of CNX
CN8 cochlear nerve fibres pathway
transverse the int auditory meatus to reach lat aspect of the medualla
terminate in dorsal and ventral cochlear nuclei in midbrain
cross over to opposite side ending in nuclei in trapezoid body
assent thru inf colluculos to medial geniculate body in thalamus to pro,aary auditory cortex
vestibular fibres of CN8 pathway
semicircular canals
-enter medulla and end in the vestibular nuclei located in the floor of the 4th ventricle
-many efferent fibres from vestibular nuclei pass to the cerebellum thru inf peduncle
what motor fibres does CN9 carry
motor fibres from nucleus ambiguous to stylipharyngeus mm
What sensory fibres does CN9 have
sensation from post 1/3 of tongue and phaeynx to sensory nucleus of CNV
parasympathetic inn to parotid gland via the otic ganglion of CNv3 from inf salivary nucleus in the medulla
Also supplies carotid body (chemoreceptors) and carotid sinus (baroreceptors)
what are the 5 afferent/efferent paths of the vagus nerve
- General somatic efferent- Nucleus ambiguous (skeletal m)
- General Visceral efferent- dorsal motor nucleus of CNX (visceromotor)
3, General somatic afferent- spinal nucleus of CNV (sensory)
- General visceral afferent- solitary nucleus (sensory)
- Special visceral afferent- base of tongue to solitary nucleus (taste)
What are the 2 parts of CN11 and where are they from
Cranial (nucleus ambiguous)
Spinal (spinal nuclei in c1-5)
How does the cranial part of CN11 form and where does it go to inn
arrises from roots from medulla that unite w spinal part before passing thru jugular foramen
-once exiting skull will joint w vagus nerve to supply mm of the palate, pharynx and larynx
How does the spinal part of CN11 form and where does it go to inn
arrises from upper 5 cerv segments, goes up thru foramen magnum to join w cranial part and then supplies scm and traps
What is supplied by CN12
Supplies all intrinsic and extrinsic mm of tongue MINUS the palatoglossus (by vagus)
what do special visceral efferents supply and what are the mm from each of the 4 arches
mm from the branchial (pharyngeal) arches
Arch 1- CNV
Arch 2- CN7
Arch 3- Stylopharyngeus
Arch 4- CNX (mm of pharynx/larynx)
