USC Keck neuroscientists conducted a simple yet effective study. They put one mouse under anesthesia to see how another mouse would react. In a journal published last week, the neuroscientists detail how the conscious mouse spent most of its time with its unconscious cage mate. To their surprise, the conscious mouse tried to revive the other. To the ordinary eye, it looks like mouth-to-mouth resuscitation.
Interestingly enough, this was not the direction they intended their original study to go.
“Actually, we found this phenomena accidentally,” said Wenjian Sun, one of the authors and researchers of the study.
Sun said the study’s main focus was that the mouse’s tongue would protrude under anesthetic.
“[The] anesthetized animals' tongue was protruding out so we started to want to know what’s the meaning of this behavior,” he said.
In an interview with New Scientist magazine, Li Zhang, co-researcher and author of the study said, “They start with sniffing, and then grooming, and then with a very intensive or physical interaction.”
In more than half of the cases, the mouse would pull on the other’s tongue in an attempt to open its airways or dislodge any object that may be stuck in their throat. When the team did place an object in the mouth, the tongue-pull method had a success rate of 80%.
“We know that humans can do CPR, trying to maintain airways during surgery or any kind of stuff,” said Guagnwei Zhang, another researcher and author of the study. “So we interpret the observation as they’re trying to help or trying to revive their group members.”
Friendship played an important role in this study. Amazingly, the active mice were more likely to help the unconscious ones when they had already been companions instead of strangers.
James Burkett, a neuroscientist outside of the study research group, said these behaviors come from oxytocin-releasing neurons in the brains of the mice - proving mice have an “altruistic impulse.”
“In this study, we found the oxytocin system plays a great, important role in this behavior,” said Sun. “How the whole oxytocin signaling pathway works in this behavior I think that will be the next step.”
If you’re curious about how this interaction looks, head over to New Scientist’s YouTube channel. There, you can see these furry critters hover over their companions and try to resuscitate them in a cute yet gross manner.