Towards an animal model of callousness.

Callous-unemotional traits - the insensitivity to other's welfare and well-being - are characterized by a lack of empathy. They are characteristic of psychopathy and can be found in other anti-social disorders, such as conduct disorder. Because of the increasing prevalence of anti-social disorders and the rising societal costs of violence and aggression, it is of great importance to elucidate the psychological and physiological mechanisms underlying callousness in the search for pharmacological treatments. One promising avenue is to create a relevant animal model to explore the neural bases of callousness. Here, we review recent advances in rodent models of pro-social choice that could be applied to probe the absence of pro-sociality as a proxy of callous behavior, and provide future directions for the exploration of the neural substrates of callousness.