Cephalic flexure

Cephalic flexure
Brain of human embryo of four and a half weeks, showing interior of fore-brain. (Cephalic flexure visible at center top.)
Latin flexura mesencephalica
Gray's subject #184 737
Code TE E5.14.3.3.0.0.3

The mesencephalic flexure or cephalic flexure is the first flexure, or bend, of the embryonic brain; it appears in the region of the mid-brain. In human embryos it generally occurs at the end of the 3rd week/beginning of 4th.

By means of it the fore-brain is bent in a ventral direction around the anterior end of the notochord and fore-gut, with the result that the floor of the fore-brain comes to lie almost parallel with that of the hind-brain.

This flexure causes the mid-brain to become, for a time, the most prominent part of the brain, since its dorsal surface corresponds with the convexity of the curve. As a consequence, the cardiac plate, which was previously anterior to the forebrain, approximates its adult location in what will become the thoracic region.

External links

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.