Effects of daily environmental enrichment on behavior and dendritic spine density in hippocampus following neonatal hypoxia-ischemia in the rat

► Decreased spine density was identified in hippocampus of the hypoxic-ischemic rats. ► Environmental enrichment enhances dendritic spine density in hypoxic-ischemic animals. ► Enrichment did not recover aversive memory deficit after hypoxic-ischemic event. ► Object-recognition memory deficit was reversed by the enrichment. ► Control and hypoxic-ischemic groups showed no motor deficits in the rota-rod test.