Lecture 22 - Skull and Cranial Nerves II Flashcards
What is CN I?
Olfactory n.
What information does CN I carry?
Olfactory information back to piriform
What are the three parts of the olfactory n.?
Olfactory filaments - bulb - tract
Where do CN I nerves enter?
Anterior cranial fossa via cribriform plate
What are vomeronasal ducts?
Associated with the flehmen reaction, pheromone detection
What is CN II?
Optic nerve
What are the three parts to the optic nerve?
Optic nerve - chiasm - tract
What infomation does CN II carry?
Information from the retinal ganglion cells to the lateral geniculate nucleus of the thalamus
What is contained within the optic nerve?
Fibers from one eye
What is contained within the optic chiasm?
Fibers from nasal retina of each eye
What is contained within the optic tract?
Ipsilateral temporal retinal fibers and contralateral nasal retina fibers
What is CN III?
Oculomotor n.
What information is carried within CN III?
Provides motor innervation to several extrinsic muscles that move the eye
Parasympathetic innervation to two intrinsic muscles of the eye
What are the actual muscles in the eye that the oculomotor neuron innervates?
Ventral oblique
Ventral, medial, dorsal recti
Levator palpebrae superioris
What are the actual muscles in the eye that CN III provides PNS innervation?
Ciliary muscles
Pupillary sphincter
What do the PNS do to the eye?
Cause the lens to become rounder and the pupil diameter to decrease