ABSTRACT

We summarize the behavioral and neuroendocrine mechanisms underlying the winner and loser effects in California mice. A number of the neuroendocrine substrates of the winner and loser effects have been characterized. For example, both the winner and loser effects impact the neural social network, particularly the ventral tegmental–nucleus accumbens pathway and the dopamine system. However, while testosterone is important for forming the winner effect, it does not appear to influence the loser effect. The winner and loser effects are representative of plasticity in behavioral and neuroendocrine mechanisms occurring in response to the social environment, thereby altering future behavior.