Figure 1.

Social defeat stress induces avoidance behaviors in adolescent c57BL/6 male mice. (a) Schematic of the social interaction/avoidance arena illustrating the geographic location and size of the interaction zone and corner zones with respect to the enclosure (circular wire cage) in which a social target (CD1 mouse) is positioned. (b) Control (non-stressed; n =10) mice showed significantly higher levels of interaction time (p<0.05), whereas defeated mice (n =10) spent significantly less time interacting (p<0.05), in the presence of a social target. (c) This avoidance behavior as a result of social defeat stress was also evident when assessing time in the corner zones, in which defeated (stressed) mice spent significantly more time in the corner zones in the presence of the social target (p<0.05). (d) No differences in locomotor activity (distance traveled in cm) during the first 2.5 min of the social interaction test was observed between the groups (p>0.05). *p<0.05, within group comparison (presence versus absence of social target). Ψp<0.05, between group comparison (control versus defeated). Data are presented as mean + SEM.