Herophilus, Erasistratus, Aretaeus, and Galen: ancient roots of the Bell-Magendie Law.

Since the early 19th century, significant controversy has persisted over the competing claims of two men, Charles Bell and François Magendie, to a pivotal discovery: that the dorsal spinal roots subserve sensation, whereas the ventral spinal roots subserve motion. However, the foundations of neuroanatomy on which Bell and Magendie built their research was formed two millennia in advance. Exploration of the work of four ancient scholars--Herophilus, Erasistratus, Aretaeus, and Galen--reveals a remarkable early appreciation of the separate neural pathways (if not the correct physiology) responsible for sensory and motor control.