Mediation of Rat's Social Dominance by Medial Prefrontal Cortex Benedict

Abstract

Social dominance in animals predicts competitive success and access to desirable resources. Dominant animals tend to
monopolise food and forage more effectively than subordinate group members. At the neuronal level, a region commonly associated with dominance-related behaviours is the medial prefrontal cortex (mPFC). Mice studies demonstrated that manipulating mPFC neurons in-vivo shifts dominance rank in the hierarchy. However, there are limited studies on rats involving the effects of in-vivo mPFC manipulation. Our study applied chemogenetic methods to investigate the role of mPFC neurons in the social dominance of male and female rats. Rats were tested in individual and group competitions to account for dominance behaviour in different interactions. In individual competitions, PFC inhibition led to a delayed decrease in male dominance behaviour yet an instantaneous decrease in female dominance behaviour. These changes did not affect dominance rank. In group competitions, the effects of mPFC inhibition were variable. Our findings suggest that mPFC activity is likely one component in a multivariate mechanism that mediates rats' social dominance.