Figure 2.

Effects of EC on anxiety-like behavior in HR and LR animals in the EPM (A) and LDB (B). Under standard housing conditions, LR animals display higher anxiety behavior relative to HRs; however, exposure to EC makes LR anxiety behavior resemble that of an HR animal. A, In the EPM, both HR and LR animals benefit from a 21 d exposure to EC with a decrease in anxiety as shown by an increase in the percentage of open arm entries; *p < 0.05, comparison between HR and HR–EC; ***p < 0.001 comparison between LR and LR–EC. B, However, in the LDB, EC exposure for 21 d significantly decreases anxiety in LR animals only as shown by a significant increase in the percentage of time spent in the illuminated compartment; **p < 0.01. Data are presented as mean ± SEM from ANOVA comparisons with Fisher's post hoc test comparisons (n = 13–15 per group) resulting from the sum of two independent cohorts containing all experimental groups.