parasympathetic
“rest and digest”
relaxation, heart rate slows, low breathing rate, tears to keep eyes lubricated…
some cranial nerves have this function
olfactory nerve
CN I - sensory
origination: olfactory receptor cells → primary olfactory cortex
passageway: cribiform foramina
func: special sensation (CHEMORECEPTION → smell)
optic nerve
CN II - sensory
o: retina → occipital lobe (visual cortex)
p: optic canal
f: special sense (vision; photoreception)
binocular vision
“crossing over” of medial aspect, lateral stays on same side.
allows us to have depth perception, stereoscopic vision (3D)
oculomotor nerve
CN III - motor
o: midbrain
p: superior orbital fissure
f: 4/6 eye movement mm → superior rectus, inferior rectus, medial rectus, inferior oblique
*parasympathetic innervation
trochlear nerve
CN IV - Motor
o: midbrain
p: superior orbital fissure
f: innervating superior oblique m. only
trigemial nerve
CN V - both
3 divisions:
V1: opthalmic
sensory; top of face
V2: maxillary
sensory; middle face + upper teeth
V3: mandibular
sensory; lower face + teeth
and motor to muscles of mastication
if dentist works on UPPER molar, where do they target / numb?
maxillary
(middle face/UPPER teeth)
trigeminal nerve: V1, V2, V3 origin to passageway
V1: pons → superior orbital fissure → supraorbital foramen
V2: pons → Foramen rotundum → infraorbital foramen
V3: pons → foramen ovale → mental foramen
abducens nerve
CN VI - Motor
o: pons → muscle
p: superior orbital fissure → CN III, CN IV, V1, VI
f: lateral rectus m. only
Facial nerve
CN VII - both
o: pons (both ways)
p: internal acoustic meatus
f:
motor → m. facial expression + parasympathetic
sensory → taste; anterior 2/3 of tongue (chemoreception)
facial nerve pathway/branch
chorda tympani branches off, passes through middle ear, goes to ant. 2/3 of tongue
facial nerve (CN VII) 5 branches that innervate muscle of facial expression
facial nerve dysfunction is called
bells palsy
facial paralysis
possible taste disturbance
dry eye/mouth
vestibulocochlear nerve
CN VIII - sensory
o: pons + medulla
p: internal acoustic meatus
f: special sense: hearing + equilibrium
glossopharyngeal nerve
CN IX - both
o: medulla
p: jugular foramen
f:
motor: stylopharyngeous m. + parasympathetic
sensory: taste; posterior 1/3 of tongue + general sensation - post 1/3 tongue of pharynx
vagus nerve
CN X - both
o: medulla
p: jugular foramen
f:
motor: muscles of pharynx + larynx + parasympathetic → thorax + abdomen
sensory: general sense - epiglottis + lower pharynx
accessory nerve
CN XI - motor
o: medulla
p: jugular foramen (CN IX, X, XI)
f: sternocleidomastoid m. + trapezius m.
hypoglossal nerve
CN XII - Motor
o: medulla
p: hypoglossal canal
f: tongue m.
damage to this nerve → push tongue towards damaged side of tongue