Order effects after blocked preexposure to two compound flavors

► We compared the effects of prolonged blocked preexposure to AX-BX or to BX-AX. ► Aversive conditioning of AX generalizes poorly to BX in the AX-BX condition. ► Preexposure to AX-BX but not to BX-AX endows B with inhibitory properties. ► The A-X association seems to be maintained throughout preexposure to AX-BX.