Unit II - C.N. IV - Trochlear Nerve Flashcards
What type of nerve is the trochlear nerve?
Somatic motor
The trochlear nucleus give rise to what type of neurons?
LMN
The trochlear nucleus is located where?
The periaqueductal gray, just caudal to the oculomotor nucleus.
The LMN from the trochlear nucleus travel _____, _____ and then exit where?
Posterior,
Cross,
midbrain just inferior to the inferior colliculi
What part of the cerebral cortex sends axons TO the trochlear nucleus?
B.A. 8
The trochlear nucleus receives fibers from what two places?
Superior colliculus
Medial longitudinal fasciculus
What does the trochlear nerve do after it leaves the CNS?
Curves around the brainstem and continues within the lateral wall of the cavernous sinus.
The trochlear nerve enters orbit through what?
Superior orbital fissure
Which muscle does the trochlear nerve supply?
Superior oblique muscle
The trochlear nerve has communication with what?
The cavernous plexus
What fibers are also in the cavernous plexus and what do they supply?
Postganglionic sympathetic fibers
Blood vessels that supply superior oblique muscles
What is the trochlear nerve named for?
The pulley-like mechanism on the medial aspect of the orbit that the superior oblique muscle passes through.
What is the PRIMARY action of the superior oblique muscle?
Depression of the eyeball
The movement of the superior oblique is down and out and the eyes move synchronously except for what movement?
convergence
