Shared neural substrates of prosocial and parenting behaviours

Humans and animals can sense the negative states of other individuals and respond with prosocial behaviour to improve their conditions^1,2. Although prosocial behaviour is hypothesized to have an evolutionary root in caring for vulnerable newborn offspring^1,3, whether the neural substrates underlying parenting may contribute to adult-directed prosocial behaviours remains largely unclear. We show that mice with higher levels of parenting exhibit more prosocial allogrooming toward stressed adults. The medial preoptic area (MPOA), a brain area involved in parenting behaviour, bidirectionally regulates allogrooming toward stressed conspecifics. Allogrooming and parenting behaviours recruit a partially overlapping neuronal ensemble in the MPOA, are both controlled by an MPOA–to–VTA pathway and are associated with dopamine release in the nucleus accumbens. Using activity-dependent labeling, we demonstrate that MPOA neuronal ensembles engaged during parenting behaviours are functionally required for allogrooming. Conversely, MPOA neurons activated during prosocial behaviour are functionally required for pup grooming. Collectively, these findings uncover a neural circuit mechanism of prosocial behaviour and reveal partially shared neural substrates between parenting and prosocial behaviours, suggesting that the neural systems evolved for offspring care may have provided a scaffold for the emergence of broader prosocial support between adults.