Figure 2.

Effect of environmental enrichment on the number of doublecortin (DCX)-positive cells in layer II of the medial prefrontal cortex of guinea pigs.

Data are represented as the number of DCX-positive cells in each high-power field. X axis is the survival time and Y axis is the mean number of DCX-positive cells in each high-power field (× 40). The difference between the environmental enrichment group and the con-trol group at the same time point was compared using unpaired t-test, while the difference between the environmental enrichment group at different survival times was compared using one-way analysis of vari-ance and Duncan's multiple range test. Data are expressed as mean ± SD of eight guinea pigs in each group at each time point. ^aP < 0.001, vs. control group at the same survival time point (0 and 10 days); ^bP < 0.01, vs. control group at the same survival time point (20 days); ^cP < 0.01, vs. environmental enrichment group at 0 day; ^dP < 0.01, vs. environ-mental enrichment group at 10 days.