CN I: Olfactory nerve

Question 1

olfactory nerves

Answer 1

• axons from cells in the epithelial layer of the olfactory mucosa of the upper nasal cavity come together to form the olfactory nerves.
• They extend superiorly, passing through the cribriform plate into the olfactory bulbs of the brain

Question 2

olfactory tracts

Answer 2

-neurons in olfactory bulb have axons come together to form the olfactory tracts; these pass information to the brain.

Question 3

Neurogenesis in CN I

Answer 3

OLFACTORY BULB CELLS ARE ROUTINELY REPLACED BY NEUROGENESIS.

Question 4

anosmia

Answer 4

• lack of smell
• The olfactory nerves can be damaged by a fracture to the cribriform plate, or they can be ripped from the cribriform plate due to a jarring head injury–both insults result in anosmia and may be accompanied by CSF rhinorrhea.

Question 5

CSF rhinorrhea

Answer 5

dripping of CSF into the nasal cavity

Question 6

Olfactory seizures

Answer 6

seizures result from damage to olfactory cortex (which is why this area is sometimes also called area tempestus); these are often preceded by olfactory hallucinations.