Experiments were performed on rats trained conditioned passive avoidance response. Acquisition and retention of memory traces were impaired after photothrombosis of the prefrontal cortex. The acyl-prolyl-containing dipeptide Noopept facilitated retention and retrieval of a conditioned passive avoidance response, normalized learning capacity in animals with ischemic damage to the cerebral cortex, and promoted finish training in rats with hereditary learning deficit. These results show that Noopept improves all three stages of memory. It should be emphasized that the effect of Noopept was most pronounced in animals with impaired mnesic function.