|Abstract||The present experiments were designed to study transfer of tolerance to frustration through paradigms. Animals were exposed to a surprising reward reduction via consummatory successive negative contrast (cSNC), enhanced counterconditioning to the reward reduction via naloxone (Nlx) administration, and tolerance to frustration was examined in these same animals via the partial reinforcement acquisition effect (PRAE), the partial reinfocement extinction effect (PREE), and anxiety induced open-field activity. The results revealed Nlx enhanced and lengthened the cSNC effect while having no effect on unshifted animals. Previously downshifted animals with previous Nlx administration in cSNC showed an elimination of the PRAE , while Nlx had no effect on the PRAE in previously unshifted animals or on PREE in all animals. Nlx exposure to previously unshifted continuously reinforced animals demonstrated an increase in ambulation in the open-field apparatus.