Trigeminal nerve

Number: V

Name: Trigeminal

Sensory, motor, or both: Both sensory and motor

Origin/Target: Pons

Nuclei: Principal sensory trigeminal nucleus, Spinal trigeminal nucleus, Mesencephalic trigeminal nucleus, Trigeminal motor nucleus

Function: Receives sensation from the face and innervates the muscles of mastication. Located in the superior orbital fissure (ophthalmic nerve - V1), foramen rotundum (maxillary nerve - V2), and foramen ovale (mandibular nerve - V3).

Description:

The trigeminal nerve is the largest cranial nerve and is the great sensory nerve of the head and face, and the motor nerve of the muscles of mastication.

It emerges from the side of the pons, near its upper border, by a small motor and a large sensory root—the former being situated in front of and medial to the latter.

The three major branches of the trigeminal nerve, the ophthalmic nerve (V1), the maxillary nerve (V2), and the mandibular nerve (V3) converge on the trigeminal ganglion (also called the semilunar ganglion or gasserian ganglion), located within Meckel's cave, and contains the cell bodies of incoming sensory nerve fibers. The trigeminal ganglion is analogous to the dorsal root ganglia of the spinal cord, which contain the cell bodies of incoming sensory fibers from the rest of the body.

The sensory function of the trigeminal nerve is to provide the tactile, proprioceptive, and nociceptive afference of the face and mouth. The motor function activates the muscles of mastication, the tensor tympani, tensor veli palatini, mylohyoid, and anterior belly of the digastric.