Galanin neurons in the medial preoptic area govern parental behaviour

Mice display robust, stereotyped behaviours towards pups: virgin males typically attack pups, whereas virgin females and sexually experiencedmales and females display parental care. Here we show that virginmales genetically impaired in vomeronasal sensing do not attack pups and are parental. Furthermore, we uncover a subset of galanin-expressing neurons in the medial preoptic area (MPOA) that are specifically activated during male and female parenting, and a different subpopulation that is activated during mating. Genetic ablation of MPOA galanin neurons results in marked impairment of parental responses inmales and females and affectsmalemating. Optogenetic activation of these neurons invirginmales suppresses inter-maleandpup-directedaggressionand inducespupgrooming.Thus,MPOAgalaninneurons emerge as an essential regulatory node ofmale and female parenting behaviour and other social responses. These results provide an entry point to a circuit-level dissection of parental behaviour and its modulation by social experience.