Anterior fasciculus proprius

Anterior fasciculus proprius (a.k.a. anterior propriospinal tract) refers to the short axons of neurons that arise from cells inside the gray matter. These ascend or descend inside the posterior part of anterior fasciculus–in close proximity to the gray matter–and eventually re-enter the gray matter. These ascending and descending branches form a short neuronal tract, called the anterior propriospinal tract, which is totally confined within the spinal cord.

Similar propriospinal tracts reside in the lateral and posterior fasciculi, as well. These include the lateral fasciculus proprius and the posterior fasciculus proprius. Collectively, these propriospinal tracts play an important role in mediating intersegmental coordination.