An anatomical and experimental study of the cerebellar nuclei and their efferent pathways in the monkey

Since the middle of the 19th century the extensive works and resultant discoveries of anatomists and physiologists have been unveiling the architecture and functions of the primate cerebellum with its associated nuclei and efferent tracts. Today the general concensus is that the cerebellum is concerned with the coordination of voluntary and/or involuntary action of striated musculature or, as Tilney ('19) expressed it, the production of synergia between agonistic and antagonistic muscle groups. The distribution pattern of the efferent fibers of the cerebellar nuclei affords an anatomical foundation for the interpretation of this functional or physiological result. These efferent fibers, which leave the cerebellum predominantly through the superior cerebellar peduncles, but also by way of the restiform bodies, terminate directly or indirectly in association with the motor pathways of vestibular, tegmental, tectal, pallidal, striatal and cortical origin. The present investigation was undertaken with the supposition that this pattern of distribution to motor centers, or correlating areas, is the predominant cerebellar pattern and that the efferent fiber systems from the primate cere-