Mice Demonstrate Innate Altruistic Rescue Behavior Linked to Oxytocin Neural Pathways

Recent research has uncovered that mice can spontaneously display rescue-oriented behaviors toward anesthetized peers, without any prior training or external reinforcement. Published in PNAS, this study provides strong evidence that prosocial actions are deeply embedded in biological processes, even in small mammals like mice.

Led by Dr. Hu Li from the Chinese Academy of Sciences and Dr. Chen Zhoufeng from Washington University School of Medicine, the research investigates the neural and molecular mechanisms behind such altruistic behaviors. Their findings suggest that the roots of prosociality are conserved throughout evolution.

In the experiments, an observer mouse was placed with an anesthetized partner and exhibited signs of stress, indicated by increased corticosterone levels. In response, the observer engaged in behaviors like allogrooming and allolicking, which not only sped up the recovery of the anesthetized mouse but also reduced the observer's own stress, highlighting a mutually beneficial interaction.

Advanced techniques such as transgenic mice, chemogenetics, optogenetics, and fiber photometry were employed to explore the underlying neural circuits. The researchers discovered that oxytocin neurons in the hypothalamus's paraventricular nucleus are activated when mice perceive distress signals from their peers. These neurons release oxytocin, which acts on specific pathways via oxytocin receptors to coordinate both emotional decoding and motor responses essential for rescue behaviors.

Specifically, pathways through the central amygdala help interpret negative emotional cues, while the dorsal bed nucleus of the stria terminalis orchestrates physical rescue actions such as licking and grooming. Oxytocin, often dubbed the "prosocial hormone," facilitates empathy, trust, and cooperative behavior by coordinating emotional and motor responses through this dual-pathway mechanism.

This breakthrough enhances understanding of the neural basis of altruism, shedding light on the evolutionary origins of empathy and social connection. By identifying the neural circuits and chemical players involved, the study challenges previous assumptions and opens new avenues for exploring complex social behaviors in mammals.

For more detailed information, see the full study: Feng-Rui Zhang et al, "Distinct oxytocin signaling pathways synergistically mediate rescue-like behavior in mice," PNAS (2025). [DOI: 10.1073/pnas.2423374122].