arcuate nucleus (medulla) arcuate nucleus (medulla) in the medulla oblongata, the arcuate nucleus is a group of neurons located on the anterior surface of the medullary pyramids. these nuclei are the extension of the pontine nuclei. they receive fibers from the corticospinal tract and send their axons through the anterior external arcuate fibers and medullary striae to the cerebellum via the inferior cerebellar peduncle. this article is about the structure in the medulla oblongata. for the hypothalamic structure, see arcuate nucleus. arcuate nucleus (medulla)transverse section of medulla oblongata below the middle of the olive. ("nucleus arcuatus" visible near bottom right.)dissection of brain-stem. lateral view. (labels for "external arcuate fibers" and "dorsal external arcuate fibers" visible at lower right.)detailsidentifierslatinnucleus arcuatus medullae oblongataeneuronames775neurolex idbirnlex_2635ta98a14.1.04.256ta26016fma72609anatomical terms of neuroanatomy arcuate nuclei are capable of chemosensitivity and have a proven role in the respiratory center controlling the breathing rate. additional images diagram showing the course of the arcuate fibers. the formatio reticularis of the medulla oblongata, shown by a transverse section passing through the middle of the olive.