Figure 1.

Adolescent social isolation behavior battery. (A) Experimental timeline. (B) In the elevated plus-maze (EPM), adolescent social isolation (SI) increases the percent time spent exploring the open arms, an effect driven by females (left), without altering locomotor activity as measured by closed arm entries (right). (C) Adolescent SI oppositely affects the percent time spent exploring the center of an open field in males and females (left) but does not affect the distance traveled in this assay (right). (D) On the social interaction test, all but group-housed (GH) females display a significant preference for a novel social partner over an empty cup, and adolescent SI increases preference (left) without impacting total time spent exploring both objects (right). (E) Adolescent SI does not affect anxiety-like behavior in the light/dark box. (F) All groups display a preference for a novel object over a familiar one, and this preference was greater in males than females but unaffected by adolescent SI (left). The total time spent exploring both objects is likewise increased in males compared to females (right). (G) Females display enhanced fear conditioning compared to males, but adolescent SI does not alter this measure. Data are expressed as means + SEM; *p < 0.05, **p < 0.01, ***p < 0.001 between groups; ^#p < 0.05, ^##p < 0.01, ^###p < 0.001 compared to null hypothesis of preference score = 1.