Mesopontine Tegmentum

Definition

The mesopontine tegmentum sits between the midbrain (also called the mesencephalon and therefore meso) and the anterior pons (and therefore pontine). The term tegmentumis a generic one that translates directly from Latin as “a cover”. The mesopontine tegmentum is therefore the upper area at the junction of pons and midbrain; it is a region of brain rather than a clearly delineated structure. It sits above the underlying pontine tissue (principally the pontine nuclei and the nuclei of the pontine reticular formation) and the fibers of the superior cerebellar peduncle, which marks an approximate border between the mesopontine tegmentum and these nuclei. Laterally, both the pontine nuclei and mesopontine tegmentum are bordered by the fibers of the lemniscal system. Medial to the mesopontine tegmentum is the central gray and in the dorsal part of the area is the inferior colliculus, though this is a structure better understood in conjunction with the superior colliculus in the...