Humans and animals share a remarkable ability to sense when others are suffering and respond with comforting actions. However, the motivation for doing so and why it sometimes fails is poorly understood.
UCLA Health researchers seek to better understand this in a new study published in Nature, uncovering brain circuits in mice that link two seemingly disparate social behaviors: caring for vulnerable offspring and comforting a suffering peer. The discovery provides the first direct neurological evidence for the long-standing evolutionary hypothesis that the biological urge to help others may have its origins in ancient mechanisms of parental care.
why is it important
Scientists have long speculated that prosocial behavior, the behavior of helping and comforting others, may have evolved from neural systems that first developed to help care for helpless offspring. However, until now, the specific brain circuits that may link these two behaviors have not been identified.
This study provides concrete neurobiological evidence for their evolutionary link, thereby providing a new framework for understanding the roots of empathy and social motivation and why they are disrupted in conditions such as depression, autism spectrum disorders, and psychiatric conditions characterized by social withdrawal.
what happened in the research
This study proved that animals that are better parents are also better helpers. Mice that spent more time caring for their young also spent more time comforting their stressed-out adult companions. This relationship was atypical and did not reflect general sociability or other self-directed behavioral tendencies.
By monitoring neural activity, the researchers found that when animals encountered stressed adults, specific neurons in the medial preoptic area (MPOA), an area known for its role in child rearing, were activated. Then, when they silenced neurons recruited during interactions with pups, the animals reduced their helping behavior toward stressed adults, demonstrating a direct causal relationship between circuits that support parenting and prosocial behavior.
Finally, the researchers identified an MPOA pathway that projects to the brain’s dopamine reward system, which bidirectionally controls both behaviors. Both comforting and parenting trigger dopamine release in the brain’s “reward center”, the nucleus accumbens, suggesting that helping others is inherently rewarding, and that this reward is mediated by the same circuits that motivate parents to care.
what they found
Taken together, these findings support the idea that evolution did not build prosocial behavior from scratch. Rather, the nervous system that evolved for offspring care may have provided a scaffold for the emergence of broader prosocial support among adults. Although MPOAs were once thought of primarily as child care centers, this study reveals that they are more general hubs for other-directed care.
what’s next
Future research will aim to understand why some individuals are more sociable than others. Researchers are also investigating whether disruption of this circuit contributes to the social deficits seen in animal models of neuropsychiatric diseases, and whether restoring its activity could be a therapeutic target.
from the experts
We show that the same circuitry that enables animals to care for their offspring also facilitates helping and comforting behaviors toward distressed adults, highlighting the common neural substrates that may shape empathy, cooperation, and the formation of cooperative social communities. ”
Weizhe Hon, lead study author and professor, Department of Neurobiology and Biochemistry, University of California, Los Angeles
sauce:
University of California Los Angeles
Reference magazines:
Sun, F. Others. (2026). Shared neural substrates of prosocial and parenting behaviors. nature. DOI: 10.1038/s41586-026-10327-8. https://www.nature.com/articles/s41586-026-10327-8.
