Radiation-induced effects on the electrical characteristics of TaOx memristive (or redox) memory are experimentally assessed. 10 keV x-ray irradiation is observed to cause switching of the memristors from high to low resistance states, as well as functional failure due to cumulative dose. Gamma rays and 4.5 MeV energy protons are not observed to cause significant change in resistance state or device function at levels up to 2.5 Mrad(Si) and 5 Mrad(Si) protons, respectively. 105 MeV and 480 MeV protons cause switching of the memristors from high to low resistance states in some cases, but do not exhibit a consistent degradation. 800 keV silicon ions are observed to cause resistance degradation, with an inverse dependence of resistance on oxygen vacancy density. Variation between different devices appears to be a key factor in determining the electrical response resulting from irradiation. The proposed degradation mechanism likely involves the creation of oxygen vacancies, but a better fundamental understanding of switching is needed before a definitive understanding of radiation degradation can be achieved.