Cranial Nerves Flashcards
1
Q
Group of cell bodies in CNS vs outside CNS
A
- in is nucleus
- out is ganglion
2
Q
1-12
A
1- olfactory
2- optic
3- oculomotor
4- trochlear
5- trigeminal
6- abducens
7- facial
8- vestibulocochlear
9- glossopharyngeal
10- vagus
11- accessory
12- hypoglossal
3
Q
Sensory
A
1,2,8
4
Q
Motor
A
3, 4, 6, 11, 12
5
Q
Both
A
5, 7, 9, 10
Some say marry money but my brother says big brains matter more
6
Q
1 olfactory
A
- nasal cavity olfactory neurones
- cribiform plate of the ethmoid bone to synapse w neurones in the olfactory bulb
- form the olfactory tract which travels to primary olfactory cortex of temporal lobe of brain
7
Q
2 optic
A
- from retina via optic canal meeting other from other eye in optic Chiat
- partial decussation then form tracts
- some synapse at suprachiasmatic nucleas in hypothalamus (sleep wake)
- some synapse at pretectal nucleas in midbrain (eye reflex)
- most synapse at lateral geniculate nucleas in thalamus
From here thalamic fibres form the optic radiations which go to occipital cortex (vision)
8
Q
Eye movements- purely motor
A
3 oculomotor
4 trochlear
6 abducens
9
Q
3 ocular motor
A
- ventral midbrain to superior orbital fissue (a foreman in sphenoid bone) to enter orbit
- splits sup and inf branch
- sup innervate levator palpebae superioris mm which raises upper eyelid and superior rectus mm which elevates the eye
- inf innervate inf oblique and inf and medial rectus mm which elevates, abduct, depress, adduct the eyeball
- some inf go to ciliary ganglion where short ciliary nn arise which provide autonomic to sphincter pupillae mm causing miosis (pupil constriction) and to ciliary mm which helps w lens accommodation for visual focusing
10
Q
4 trochlear nn
A
- from dorsal midbrain and follows ocularmotor nn through sup orbital fissue to orbit
- innervates sup oblique mm which abducts, depresses and internally rotates the eye
11
Q
6 abducens
A
- from pons through sup orbital fissue to orbit
- innervates lateral rectus mm which abducts the eye
12
Q
5 trigeminal
A
- from pons to trigeminal ganglion and splits into ophthalmic, maxillary and mandicular
- ophthalmic through sup orbital fissue to go give sensory info to skin of upper eyelid, nose, forehead and scalp
- max exits via foreman rotundum and provides sensory info to maxilla, nasal cavity, palate, skin of cheeks
- mand exits via foremen ovale provides sensory and motor (mastication V3), sensory lower lip, lower teeth, chin, temporal region of scalp
13
Q
7 facial
A
- from pons to and enters into temporal bone of skull through internal acoustic meatus to reach geniculate ganglion
- gives rise to 3 inter cranial branches, greater petrosal n (autonomic lacrimal, nasal, palatine, pharyngeal glands); stapedius (motor to stapedium mm of middle ear); chorda tympani (sensory to taste buds and ant 2/3 of tongue)
- rest leaves via stylomastoid foremen and splits into extracranial tempora, zygomatic, buccarati, mandibular, cervical= all facial expression
14
Q
8 vestibulocochlear
A
- from pons to internal acoustic meatus where it splits into cochlear nn (hearing receptors in cochlear) and vestibular nn (equilibrium receptors in vestibule)
15
Q
9- glossopharyngeal n
A
- from medulla and exits skull through jugular foreman
- branches to innervate tongue and pharynx and motor to stylophayngeas mm which elevates the pharynx in swallowing
- and parasympathetic motor to parotid glands
- sensory to taste post 1/3 tongue
- pharynx touch and pain sensory
- convoys info from chemoreceptors in carotid bodies which help regulate respiration by monitoring levels of O2 and CO2 in blood
- convays info from barorecptors of carotid sinus which help monitor bp
