part_of part of part of organ part medulla oblongata bulb bulbus medulla oblonzata metepencephalon medulla Organ component of neuraxis that has as its parts the medullary reticular formation, inferior olivary complex and cochlear nuclear complex, among other structures[FMA]. The medulla oblongata lies directly above the spinal cord and controls vital autonomic functions such as digestion, breathing and the control of heart rate[GO]. brainstem ectoderm-derived structure myelencephalon structure with developmental contribution from neural crest