Figure 4.

Involvement of the dorsal hippocampus. A, Expression of mRNA for Arc/Arg3.1 in cerebellum (Cereb.) and hippocampus (Hipp.) of C57BL/6J mice undergoing an experience trial in the compartmented arena (Experience), an open field (Open Field), or exposed to female mice introduced into a compartment of their home cages (Female). For each brain region, values are expressed as percentage of the Open Field group. *p < 0.05; **p < 0.01 (Dunn's multiple comparisons after Kruskal–Wallis test) compared with the Experience group. The first and second values for n indicate the number of mice used for the hippocampus and cerebellum, respectively. B, Mice injected with vehicle (NaCl) but not those injected with anisomycin display a preference for the female's location during the recall trial. *p < 0.05 (Mann–Whitney U test); ⁺⁺p < 0.01 (Wilcoxon signed-rank test) compared with chance level of 0.5 (depicted with a dashed line).