Olfactory nerves

The olfactory nerve (I) is a sensory nerve responsible for the sense of smell. It is formed by numerous nonmyelinated axons arising from olfactory receptor cells located in the olfactory epithelium of the ethmoidal labyrinth and the dorsal part of the nasal septum.

Number : I

Sensory, motor, or both : sensory

Origin : olfactory epithelium covering approximately one half of the ethmoidal labyrinth and the dorsal part of the nasal septum.

Route / Reports : the axons pass from the caudal part of the nasal cavity through numerous foramina of the cribriform plate of the ethmoid bone and enter the cranial cavity to reach the ventral surface of the olfactory bulbs. They do not form a single discrete nerve trunk.

Distribution : olfactory bulbs, where the olfactory axons synapse. The terminal nerve and vomeronasal nerve are also included with the olfactory nerves; they arise from the vomeronasal organ and enter the olfactory peduncle and olfactory bulb, respectively.

Description : The olfactory nerve is composed of numerous nonmyelinated sensory axons originating from receptor cells in the olfactory mucosa. These fibers pass through multiple foramina in the cribriform plate of the ethmoid bone and terminate in the olfactory bulbs, where they synapse. Unlike most cranial nerves, the olfactory nerve does not form a single identifiable nerve trunk.