Acquisition and Extinction of Avoidance Response by Social Interaction in Rats

In rodents, many forms of behavior (avoidance, food choice, exploring, etc.) have been shown to be transmitted through social interaction. Previous psychological studies have shown that acquisition of avoidance behavior is under the influence of social interaction but detail analyses have not been done. In the present study, we studied how learned avoidance behavior is influenced by interacting with other rats which have different experiences to foot shock using passive avoidance paradigm. Rats received electrical shocks in the dark compartment and avoided entering there were used as subjects. In Experiment 1, the latency to enter the dark compartment was measured under three different conditions; without any partner (ALONE), with a shock-received partner (wSHOCK) and with a unshocked-naive partner (wNAIVE). The latencies of wSHOCK and wNAIVE to enter the dark compartment were shorter than that of ALONE. In Experiment 2, the effects of other rats’ behavior on reinstate of avoidance were examined. The subject rats used in the Experiment I were put in the dark compartment without electrical foot shock and habituated to the compartment. Then the latencies to enter the dark compartment were measured in absence or presence of demonstrator rat which received electric foot shock in front of the subject rats. The demonstration of receiving foot shock by other rats enhanced avoidance responses. These results suggest that learned avoidance may be modified by partners’ behaviors in reciprocal fashion.