Fig. 1.

Effects of social defeat stress and environmental enrichment on behavior and plasma corticosterone.

In the open field, SD had no effect on exploratory behavior but EE increased total activity (A) and time in the center zone (B). In the elevated plus maze, SD resulted in decreased exploration of the open arms (C). SD also decreased sucrose preference (D), decreased latency to immobility in the forced swim test (E), and increased plasma Cort (F). All of the stress-induced changes were normalized by treatment with EE. Graphs indicate mean ± standard error of the mean. *p < 0.05, **<0.01, ***<0.001.