From the Classic to Modern Neuromorphology, an Introductory Overview

Most of you will know that the human brain begins as a tiny epidermal plate, called the ‘neural plate’, whose lateral edges rise upward, approach each other and finally fuse, so that the originally flat neural plate is transformed into a hollow neural tube with a fused roof plate (left panel). Note that this closing process does not occur synchronously over the length of the developing central nervous system (CNS). It begins in the future cervical (neck) region and proceeds from there anteriorly and posteriorly, so that the initially large anterior and posterior neural openings or ‘neuropores’ become progressively smaller and finally disappear. Experimental fate-mapping has shown that the rostralmost closing point lies at the locus of the future anterior commissure.