The lateral proper fasciculus (lateral basis bundle) constitutes the remainder of the lateral column, and is continuous in front with the anterior proper fasciculus

Anterior proper fasciculus

The remaining fibers of the anterior funiculus constitute what is termed the anterior proper fasciculus, fasciculus proprius, or fasiculus proprii .It consists of...

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It consists chiefly of intersegmental fibers which arise from cells in the gray substance

Grey matter

Grey matter is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil , glial cells and capillaries. Grey matter contains neural cell bodies, in contrast to white matter, which does not and mostly contains myelinated axon tracts...

, and, after a longer or shorter course, reënter the gray substance and ramify in it.

Some of its fibers are, however, continued upward into the brain under the name of the medial longitudinal fasciculus

Medial longitudinal fasciculus

The medial longitudinal fasciculus is a pair of crossed fiber tracts , one on each side of the brainstem. These bundles of axons are situated near the midline of the brainstem and are composed of both ascending and descending fibers that arise from a number of sources and terminate in different...

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