Pre-exposure to the aversive chamber promoted discrimination and memory strength at both recent and remote retention tests. (A) Experimental timeline. Rats were given a 5 min pre-exposure to the aversive chamber, and the next day underwent IA training (all with the 60 sec condition). Rats were then tested at recent and remote retention tests in each chamber. (B) Rats discriminated at both recent and remote retention tests, with a significant reduction in aversive context latencies (i.e., memory strength) between recent and remote time points. (C, left) Males discriminated at the recent retention test and generalized at the remote retention test. (Right) Females discriminated at both recent remote retention tests, with a significant reduction in aversive context latencies (i.e., memory strength) between recent and remote time points. (D, top) Discrimination ratio calculation. (Bottom) Discrimination ratios calculated for males and females indicated enhanced discrimination in females at the recent retention test compared to males. (E, left) Testing order had no effect on retention latencies at the recent retention test. (Right) At the remote retention test, rats tested in the aversive chamber first generalized, whereas rats tested in the neutral chamber first discriminated. (*) P < 0.05, (**) P < 0.01, (***) P < 0.001, (****) P < 0.0001.
