PEA-15 knockout mice exhibit irregular reductions in activity and higher stress reactivity. (A) Average weight per group across the nine weeks of experimentation is depicted. (B) Stress induced boli deposited in the Elevated Plus Maze is shown. (C) Average time per group spent in the open arms of the Elevated Plus Maze during the 4 min session is shown. (D) Average number of crossings into open and closed arms in the Elevated Plus Maze is depicted. (E) Shown is the average percent of time per group spent in the center (stressful) quadrants of the Open Field. (F) Total average revolutions made in the Running Wheel task for each group is shown. Data are shown as mean values ± SEM; n values are indicated. "*" indicates a P value < 0.05.