Manganese doped perovskites are promising materials for non-magnetic data storage. Systems with low doping concentration, such as Mn:YAlO3 are high-quality optical crystals, demonstrating significant photorefractive effect. Optically and electrically induced quasi-permanent change in low-field conductivity was observed in the materials with high concentration of manganese such as single crystals and films of LaGa
O3 (x= 0.1–1). These memory effects can last for a long time at room temperature and can be easily erased by heating up to 230 C. We explain our experimental results by photoinduced or thermoinduced local phase transition with the oxidation of Mn ions.