The production of new, maturing neurons by neural stem and progenitor cells. Rapid and widespread neurogenesis obviously occurs in the fetal brain in humans and other animals, but neuroscientists long believed that neurogenesis essentially does not occur in the adult human brain.
However, over the past two decades, research has shown that it does in fact occur in the dentate Gyrus of the hippocampus and possibly other brain regions. This “adult neurogenesis” appears to be vital for normal learning and memory, and may help protect the brain against stress and depression.