Definition: Bluish region in the superior angle of the fourth ventricle floor, corresponding to melanin-like pigmented nerve cells which lie lateral to the ponto-mesencephalic central gray (griseum centrale). It is also known as nucleus pigmentosus pontis.
Other names Pontis, Nucleus Pigmentosus; Nucleus Pigmentosus Pontis; Locus Ceruleus; Locus Caeruleus