A praying mantis (Stagmatoptera biocellata) shown a bird (Padda oryzivora) displays a frightening response calleddeimatic reaction (DR). Habituation of this response takes place after repeated presentation of the bird (no-DR training). Anoxia with nitrogen impairs no-DR retention but after 5 days of training the no-DR memory becomes completely consolidated. Paper high voltage electrophoresis of a gel filtration of brain extracts revealed three distinctive cationic spots (+1, +2 and +3) and three anionic ones frequently fused to form a single spot (-complex). Changes in density of these spots during no-DR training were observed, but only increase in density at +3 proved to be clearly correlated with memory consolidation (Maldonado 1980).