Cranial nerves I, II, VIII (Special Senses) Flashcards
What are the names of CN I, II, VIII
What is the main characteristic of these 3 nerves
I, Olfactory
II, Optic
VIII, Vestibulocochlear
SENSORY ONLY
Describe the innervation pathway of the olfactory nerve
Olfactory nerves found in nasal epithelium
Impulse enters olfactory bulb via cribinform plate => synapses onto 2nd order neurones => olfactory tract
Olfactory tract => olfactory cortex in ant side of temporal lobe => olfactory tubercle and piriform cortex
Impulses also sent to amygdala, entorhinal cortex, hippocampus and thalamus
Which structure in the olfactory pathway is visible on the brain
Olfactory tract
What foramen is associated with the olfactory nerve
Cribinform plate on ethmoid
Describe the innervation pathway of the optic nerve
Lateral light falls on nasal retina
Optic nerve crosses to contralateral side in optic chiasma
OR
Medial light falls on temporal retina
Optic nerve stays on ipsilateral side in optic chiasma
Optic nerve synapses onto 2nd order neurones in LGN of the thalamus
Optic radiations onto visual cortex in occipital lobe
What structure in the optic pathway is visible on the brain
Optic chiasma above the 2 maxillary bodies
What foramen is associated with the optic nerve
Optic canal
Where does the vestibulocochlear nerve emerge from in the brainstem
Where are the nuclei located
Cerebellar pontine angle (CPA)
Nuclei found laterally in floor of 4th ventricle
Describe the innervation pathway of the vestibulocochlear nerve
Hair cells of inner ear sends impulse
Vestibulocochlear nerve => vestibular ganglia
Vestibular and cochlear nuclei in lateral floor of 4th ventricle at CPA
Mediate balance and hearing
What foramen is associated with the vestibulocochlear nerve
Internal acoustic meatus with facial
Via petrous part of temporal
