The fact that new neurons are generated in adult mammalian brain (including humans) is now well established, but the functional significance of adult neurogenesis remains uncertain. In the dentate gyrus of hippocampal formation, on the border of the hilus and granule cell layer, resident stem cells continuously proliferate and neuroblasts migrate into the granule cell layer, giving rise to new differentiated neurons that integrate into the existing circuitry of the dentate gyrus and hippocampus. In the normal brain, these adult-born granule cells have been proposed to store newly acquired memories. In the epileptic brain, the functional significance of new granule cells is not understood. Especially, given that neurogenesis in the dentate gyrus is increased after seizures, investigators have hypothesized that these new-born granule cells may have a role in epileptogenesis.