Motor Systems: Cranial Nerves Flashcards
medial longitudinal fasciculus
interconnects CNs III, IV, VI in order to move both eyes at the same time
CN III function
motor to ipsilateral dorsal/ventral/medial rectus, ventral oblique, and levator palpebrae
where is the cell body of CN III located
caudal oculomotor nucleus
located in midbrain (rostral colliculi)
CN III dysfunction
lateral strabismus
ptosis
CN IV function
motor to contralateral dorsal oblique
where is the cell body of CN IV located
trochlear nucleus
located in midbrain (caudal colliculi)
CN IV dysfunction
dorsolateral strabismus
ptosis
CN V function
motor to ipsilateral muscles of mastication
where is the cell body of CN V located
motor nucleus of trigeminal nerve
located in pons (near peduncles)
CN V dysfunction
atrophy of muscles of mastication (temporalis, masseter)
enophthalmos from pterygoid atrophy
inability to retract globe
CN VII function
motor to ipsilateral muscles of facial expression (ear, eyelid, nose, cheeks, lips)
where is the cell body of CN VII located
facial nucleus
locate in rostral medulla (caudal peduncles)
CN VII dysfunction
facial asymmetry (ear/lip droop, small palpebral fissure)
chronic –> contraction causing deviation of nose/upper lip toward affected side
CN IX, X, XI function
motor to ipsilateral pharynx, larynx, trapezius, sterno/cleidocephalicus muscles
where are the cell bodies of CNs IX, X, XI located
nucleus ambiguus
located in medulla (extends to obex)
