Isolation of neural stem cells/neural progenitor cells (NSC/NPC) from extra-neural origin, or adult stem cells able to specify into NSC/NPC in vitro under particular cell culture conditions, offers an interesting alternative experimental model with prospective benefits in basic research and translational medicine. In this chapter, we describe a procedure of isolation and culture of ovarian cortical cells that consistently allows the spontaneous generation of a large number of neurospheres (NS), and the methods to demonstrate that their integrating NSC/NPC self-renew and are able to differentiate into neurons and glia, during the NS assay.