Loss of hippocampal neurogenesis, increased novelty-induced activity, decreased home cage activity, and impaired reversal learning one year after irradiation of the young mouse brain

► We evaluated the long-term effects after irradiation to the young mouse brain. ► Hippocampal proliferation was still markedly reduced. ► Neurogenesis had been almost completely ablated and gliosis was seen. ► Place learning was unaffected but reversal learning was impaired.