Neuropoiesis is the process by which neural stem cells differentiate to form mature neurons, astrocytes, and oligodendrocytes in the adult mammal.
While rapid neurogenesis was known to occur in the early stages of life, the production and differentiation of neural stem cells was believed to cease upon maturity.
In the late 1970s Steven Goldman used this technique to examine the vocal control centers of songbirds, and he found widespread evidence of adult neurogenesis in this area of a canary's brain.
[3] The most recognized initial sites of neuropoiesis ending with neurons in adults are the subventricular zone (SVZ), the thin layer of cells just beneath the surface of the lateral ventricles of the brain, and the dentate gyrus of the hippocampus.
Towards this end, many researchers are attempting to control the differentiation and proliferation of neural stem cells in vivo by altering the expression of key genes such as presenilins and the sonic hedgehog pathway.