In the trunk region of the embryo, migration is along 2 different pathways. Animation of migration Neural crest cells lying adjacent to the posterior segment of the somite migrate anteriorly over the neural tube, placing themselves adjacent to the anterior section. These cells then also enter the anterior portion of the somite and follow the same pathway. Animation of migration of cells placed at posterior somite Neural crest cells from the anterior and posterior portion of the somites following this pathway give rise to the sympathetic and parasympathetic dorsal root ganglia and cells of the adrenal medulla. The second route that can be taken by neural crest cells of the trunk is to travel between the ectoderm and the somites.
Cells travel along the dorso lateral surface of the somite.
These cells migrate into the most ventral region of the ectoderm. Here the cells develop into pigment cells of the skin. Neural crest cells within the rhombomeres acquire a positional value which determines when and where they migrate.