Table 1.

Timing of Structural Development of the Human Brain

Time from conception	Developmental Process	References
3–4 weeks	Formation of neuroectoderm	96
3–4 weeks	Primary neurulation	15,86,96
5–10 weeks	Formation of prosencephalon and hemispheres	96
5–10 weeks to ? years postnatally	Cerebral angiogenesis and formation of the blood-brain barrier	66
7–10 weeks	Generation of the subplate layer of neurons (from germinal matrix)	46
10–15 weeks to ? years postnatally	Neurogenesis	96
12–24 weeks	Neuronal migration	27,28,78,79,85,96
16–24 weeks	Blood vessel density in subcortical white matter is low	65
20 weeks to ? years postnatally	Synaptogenesis and synaptic stabilization	12,16,71
20 weeks to ? years postnatally	Gliogenesis	9,14,95,96
22–36 weeks	Maximal thickness of the subplate layer of neurons (from germinal matrix) is reached	46
23–29 weeks	Cortical folding and spontaneous EEG bursts; delta brushes	10,30,43,45,63
28–36 weeks	Blood vessel density in deep white matter is low	37,65
28 weeks to ? years postnatally	Neuronal and glial apoptosis	96
36 weeks to ? years postnatally	Myelination	9,96