Fig. 2.

Aging-induced behavioral differences between young (5 mo old) and middle-aged (12 mo old) female mice. A: younger female mice covered more distance in the elevated plus maze (EPM) assay compared with middle-aged female mice. B: time spent in open arms was significantly higher in middle-aged compared with younger female mice in the EPM. C: aging reduced general locomotor activity and exploratory behavior. D: middle-aged female mice spent more time in the center of the maze, as compared with younger female mice (**P < 0.01). E: middle-aged female mice showed less interest in exploring objects and lower exploratory activity. F: there was no significant difference in novel object interaction time (n = 7/group; *P < 0.05, **P < 0.01, ***P < 0.005).