nuclei located in the spinal cord (T1L2, S2S4) and in the brainstem (Edinger-Westphal nucleus, superior and inferior salivatory nuclei, dorsal vagal nucleus and parts of the ambiguus nucleus) from which general visceral efferent preganglionic fibers arise; may be sympathetic (T1-L2) or parasympathetic (craniosacral); hypothalamic nuclei/areas function in concert with autonomic nuclei.