cranial nerves Flashcards
- part of the PNS (connect to brain)
- 12 pairs
- roman numerals
- 3 sensory
- 5 motor
- 4 mixed
- 4 automatic - parasympathetic functions (smooth muscle, cardiac muscle, glands) (III, VII, IX, X)
description of cranial nerves
olfactory (I), optic (II), vestibulocochlear (VIII)
sensory cranial nerves
through cribriform plate of ethmoid
- one of the few places neurons can regenerate
olfactory (CN I) location
smell
olfactory (CN I) function
posterior from eyeball to optic chiasm
optic (CN II) location
sight
optic (CN II) function
petrous part of temporal bone to junction of pons/medulla
vestibulocochlear (CN VIII) location
hearing and balance
vestibulocochlear (CN VIII) function
oculomotor (III), trochlear (IV), abducens (VI), accessory (XI), hypoglossal (XII)
motor cranial nerves
junction of midbrain/pons into posterior orbit
oculomotor (CN III) location
voluntary
- 4 external ocular muscles (superior rectus, inferior rectus, medial rectus, inferior oblique)
oculomotor (CN III) somatic motor function
involuntary
- constrict the pupil
- accommodation (lens adjustment)
oculomotor (CN III) autonomic motor function
lateral pons into orbit
trochlear (CN IV) location
innervates superior oblique
trochlear (CN IV) function
junction of pons/medulla into orbit
abducens (CN VI) location
innervates lateral rectus
abducens (CN VI) function
lateral medulla/spinal cord into posterior/lateral neck
accessory (CN XI) location
innervates trapezius and sternocleidomastoid
accessory (CN XI) function
medulla to tongue
hypoglossal (CN XII) location
innervates intrinsic and extrinsic tongue muscles
hypoglossal (CN XII) function
stick tongue out; tip will deviate towards the side that is not working
- can be caused by tumor/stroke
hypoglossal nerve test
trigeminal (V), facial (VII), glossopharyngeal (IX), vagus (X)
mixed (sensory and motor) cranial nerves
lateral pons
trigeminal (CN V) location
opthalmic (V1), maxillary (V2), mandibular (V3)
divisions of trigeminal nerve
