tr eatment. If th e PRE is caused by some typ e of conditioned emotional response such as frus t ration (Amsel, 1958) , it co uld be that ECS in terferes in some way with the condition ed frustrati ve reacti on , resulting in aloss of th e PRE . This inte rfe rence, how ever , appears to differentially affect VR · and FR-trained subjec ts. Th e combine d find ings suggest that reinfor cement schedule is an imp ortant variable in determinining the effects of ECS, although it is not clear that a memory cons olidation hypothesis would suggest it.
REFERENCESAmsel, A. The role of frustrative nonrew ard in noncontinuous