Sensory, hormonal, and neural basis of maternal aggression in rodents.

We review existing knowledge of the neural, hormonal, and sensory basis of maternal aggression in the female rat. Although females may express different kinds of aggression, such as defense or dominance, the most frequent and conspicuous form of aggressive behavior among females is the one associated with motherhood. Maternal aggression occurs in various vertebrate and invertebrate species; however, our emphasis will be on maternal aggression in rats because most of the physiological investigations have been performed in this species. Firstly, we address those factors that predispose the female to attack, such as the endocrine profile, the maternal state, and the stimulation provided by the pups, as well as those that trigger the aggressive response, as the intruder's characteristics and the context. As the postpartum aggression is a fundamental component of the maternal repertoire, we emphasize its association with maternal motivation and the reduction of fear and anxiety in dams. Finally, we outline the neurocircuitry involved in the control of maternal aggression, stressing the role of the ventro-orbital region of prefrontal cortex and the serotoninergic system.