Judged: two independent readers; copy check clear.
locus ceruleus
locus ceruleus The locus ceruleus is a bluish area at the upper part of the floor of the fourth ventricle.
The locus ceruleus is a bluish area at the upper part of the floor of the fourth ventricle. Its color corresponds to melanin-like pigmented nerve cells located to the side of the periaqueductal gray.