Mesencephalic nucleus of the trigeminal nerve

Last revised by William Howden on 9 Apr 2023

The mesencephalic nucleus of the trigeminal nerve is one of three major nuclei that make up the trigeminal sensory nerve nuclear complex along with the main sensory nucleus and the spinal nucleus 1-2.

Gross anatomy

The mesencephalic nucleus is a paired structure located at the mesopontine junction which projects cephalad through the midbrain. It is situated along the anterolateral aspect of the periaqueductal grey matter and lies ventral to the inferior colliculi at the level of the midbrain.

It lies superior to the main sensory nucleus of the trigeminal nerve with which it is continuous within the pons.

The mesencephalic nucleus is the only nuclei in the central nervous system to contain the cell bodies of first order sensory neurons (which are usually contained within ganglia), making it anatomically unique 3.

Innervation

The mesencephalic nucleus contains first-order afferent cells that receive facial proprioceptive impulses from the hard palate, teeth and temporomandibular joint.

A sickle-shaped mesencephalic tract descends to the trigeminal nerve motor nucleus and conveys impulses that control mastication and bite force and also facilitate monosynaptic jaw jerk reflexes.

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.