Differential effectiveness of various prior-cuing treatments in the reactivation and maintenance of memory.

In 3 experiments, changes were examined in the characteristics of newly acquired and reinstated memories over time in preweanling rats. Experiment 1 indicated that forgetting after conditioning was monotonic, with the upper limit of retention at approximately 120 min posttraining. In Experiment 2, Ss were exposed to various elements of the training episode before testing, after either a 3- or a 24-hr retention interval. The results indicated that the prior-cuing treatments were differentially effective and that the effectiveness of a reactivation treatment may change as a function of the retention interval. Experiment 3 indicated that Ss expressed a conditioned aversion at much longer intervals following reactivation treatments than after initial conditioning. Furthermore the susceptibility of the reinstated memory to forgetting was dependent on the prior-cuing treatment used. The results suggest a change in the memorial representation of the conditioning episode over time.