Figure 1.

Effect of ZnR on fear extinction using a paradigm consisting of 15 CS presentations during extinction retrieval. ZnR beginning 21 d before conditioning (Cond) rescued impaired extinction learning and retrieval in S1 mice and facilitated extinction learning in B6 mice, relative to control diet (Ctl), but did not lead to savings in extinction (re)learning during extinction retrieval (15 CS presentations) (n = 8 per group). Data are presented as means ± SEM. *p < 0.05, S1 control diet versus B6 control diet; ^#p < 0.05, S1 control diet versus S1 ZnR; ^†p < 0.05, B6 ZnR versus S1 control diet; ^§p < 0.05, B6 control diet versus B6 ZnR.