Editing Neurulation (section)

== Early brain development ==
The anterior portion of the [[neural tube]] forms the three main parts of the brain: the [[forebrain]] ([[prosencephalon]]), [[midbrain]] ([[mesencephalon]]), and the [[hindbrain]] ([[rhombencephalon]]).<ref name="Developmental biology">{{cite book|last1=Gilbert|first1=Scott F.|last2=College|first2=Swarthmore|last3=Helsinki|first3=the University of|title=Developmental biology|date=2014|publisher=Sinauer|location=Sunderland, Mass.|isbn=978-0878939787|edition=Tenth}}</ref> These structures initially appear just after neural tube closure as bulges called [[brain vesicle]]s in a pattern specified by anterior-posterior patterning genes, including [[Hox genes]], other [[transcription factor]]s such as Emx, Otx, and Pax genes, and secreted signaling factors such as [[fibroblast growth factor]]s (FGFs) and [[Wnt signaling pathway|Wnts]].<ref>{{cite book|editor1= Eric R. Kandel|title=Principles of neural science|date=2006|publisher=McGraw Hill|location=Appleton and Lange|isbn=978-0071390118|edition=5.}}</ref>  These brain vesicles further divide into subregions. The prosencephalon gives rise to the [[telencephalon]] and [[diencephalon]], and the [[rhombencephalon]] generates the [[metencephalon]] and [[myelencephalon]].  The hindbrain, which is the evolutionarily most ancient part of the [[chordate]] brain, also divides into different segments called [[rhombomeres]].  The rhombomeres generate many of the most essential neural circuits needed for life, including those that control respiration and heart rate, and produce most of the [[cranial nerve]]s.<ref name="Developmental biology"/>  [[Neural crest cell]]s form [[ganglia]] above each rhombomere.  The early neural tube is primarily composed of the [[germ layer|germinal]] [[neuroepithelium]], later called the [[ventricular zone]], which contains primary [[neural stem cell]]s called [[radial glial cell]]s and serves as the main source of [[neuron]]s produced during brain development through the process of [[neurogenesis]].<ref>{{cite journal|last1=Rakic|first1=P|title=Evolution of the neocortex: a perspective from developmental biology.|journal=Nature Reviews. Neuroscience|date=October 2009|volume=10|issue=10|pages=724–35|pmid=19763105|doi=10.1038/nrn2719|pmc=2913577}}</ref><ref>{{cite journal|last1=Dehay|first1=C|last2=Kennedy|first2=H|title=Cell-cycle control and cortical development.|journal=Nature Reviews. Neuroscience|date=June 2007|volume=8|issue=6|pages=438–50|pmid=17514197|doi=10.1038/nrn2097|s2cid=1851646}}</ref>