Fig. 2.

Anxiety-like behaviors in the elevated-plus-maze and open field. Late in the dark phase compared with early, aged mice spend less time exploring the open arms (A), make less entries into the open arms (B), and have a greater latency to first enter the open arms (C). In the open-field test, aged mice exhibit less exploratory rearing behavior late in the dark phase compared with early (D). n = 3–7 mice per group. Mean ± SEM *P < 0.05 aged early vs. aged late; **P < 0.01 aged early vs. aged late; ^†P < 0.05 aged late vs. all other groups; ^††P < 0.01 aged late vs. all other groups.