Fig. 1: The social stress leads to fear memory and anxiety-like behavior in mice.

A Illustrates the timeline to induce social stress by a resident/intruder paradigm, and the behavioral tasks to assess fear memory and anxiety. Male C57BL/6 mice in postnatal week three underwent a week adaptation period. Subsequently, they were assessed in a social interaction cage and an elevated-plus maze to collect basal self-control data. For the intruder group, mice were exposed to daily social stress by placing them in front of an aggressive CD-1 mouse, which attacked the C57 mice, for a total of three weeks. To reduce distress, the frequency of attacks was reduced to once every two days during the third week, as indicated by a dashed line. Following exposures to this social stress, mice were reevaluated in the social interaction cage and elevated-plus maze to assess the formation of fear memory and the level of anxiety, respectively. B Shows heat-maps of the social interaction cage test results from C57 mice in the control and intruder groups, before and after social stress, with colors indicating activity levels from low (blue) to high (red). C Shows statistical analyzes of the stay time in the interaction zone before and after the resident/intruder paradigm for control mice (blue spots) and intruder mice (red spots; mean ± SEM, students’ t test, ****p < 0.0001). D Shows heat-maps about the tests on the elevated-plus maze from C57 mice in the control and intruder groups before and after the social stress, in which the colors from blue to red indicate activity levels from low to high. E Shows statistical analyzes of the stay time in the open arms before and after the resident/intruder paradigm for control mice (blue spots) and intruder mice (red spots; mean ± SEM, students’ t test, ***p < 0.001).