Figure 1.

In rodent brains, two main areas maintain neurogenesis: the SVZ of the LV.

In the subventricular zone (SVZ), nascent neurons migrate long distances to the olfactory bulb (OB) along the dorsal migratory stream (depicted with green lines) and the subgranular zone (SGZ) of the dentate gyrus (DG). Nascent neurons then migrate short distances to form the granule cell layer of mossy fiber pathways and synaptic connections with Cornu Ammonis region 3 (CA3) neurons (DG and CA3 depicted with red lines). In the SVZ, neural stem cells (NSCs) are termed B-type cells, a subpopulation of quiescent cells with an astrocyte-like appearance. Morphologically, B cells have a long base protrusion terminating in blood vessels and an apex that terminates on the surface of the ventricle. Then, B cells differentiate into transport amplifying cells, called C cells, and later into neuroblasts, which are also called A cells. In the SGZ, NSC cells are called type 1 cells, which are similar to B cells of the SVZ. Type 1 cells differentiate into intermediate progenitors, which are called type 2 cells. Type 2 cells give rise to type 3 cells or neuroblasts (not shown), which form mature cells in contact with pyramidal cells. Created with Adobe illustrator. LV: Lateral ventricle; SVZ: subventricular zone.