Introduction:
- Olfactory nerve is first cranial nerve.
- Both olfactory and optic nerve attaches to forebrain.
- No nuclei present, Olfactory nerve responsible for smell.
- Purely sensory.
- Each olfactory nerve consists of 20 minute bundle of non-myelinated nerve fibre.
FEATURES:
Primary sensory neuron:
- Present in epithelial lining of the nasal cavity.
- undergo continuous turnover.
👉Functional component- special sensory afferent fibres.
They carry sensation of smell from olfactory region of nasal cavity.
↓
Terminate in olfactory bulb.
Course:
✹Distributes the olfactory region of nasal cavity.
Why infection from nose can spread into brain?
- Bundles of olfactory nerve surrounded by 3 meninges near cribriform plate- piamater ,arachnoid mater, duramater.
- Thus, provide communication between subarachnoid space & lymphatics of nasal mucosa.
