The olfactory filaments are fine nerve fibers that serve as olfactory receptors and altogether constitute the olfactory nerve (1st cranial nerve).
The olfactory filaments are 20-25 small bundles of unmyelinatednerve fibers. They conduct the electrical impulses of the olfactory cells of the nasal mucosathrough the cribriform plate of the ethmoidal boneand mainly end at dendrites of mitral cells in the olfactory bulb.