Where in the brain does adult neurogenesis occur?
New neurons are not created equally throughout the adult mammalian brain; only certain regions possess populations of active progenitor cells.17–20 Substantial adult neurogenesis occurs in only the dentate gyrus of the hippocampus and the subventricular zone adjacent to the lateral ventricles.3,4,8 It has been estimated that about 9000 new neurons are created in the mature rat dentate gyrus every day.21 The number of new neurons created in the subventricular zones has not yet been estimated, but it is likely to exceed the number created in the dentate gyrus.
