Adult neurogenesis, a process of generating functional neurons from adult neural precursors, occurs throughout life in restricted brain regions in mammals. These are the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle, the rostral migratory stream to the olfactory bulb.

In the adult subventricular zone, proliferating radial glia-like cells give rise to transient amplifying cells, which in turn generate neuroblasts. In the rostral migratory stream, neuroblasts form a chain and migrate towards the olfactory bulb through a tube formed by astrocytes.