A new study on mice suggests that the ability to empathize with others—to sense and act on their emotional states—has a genetic basis. Researchers from the University of Wisconsin-Madison and Oregon Health and Science University had a bunch of highly social mice watch while they put another mouse in a cage. The mice then heard a 30-second tone at the same time the mouse in the cage (now out of view) was given a mild foot shock, causing it to squeak in distress.
When the gregarious mice were later put in the cage and the tone was played, they showed clear physiological signs of aversion (like freezing in place), even though they were never shocked. These mice had learned to associate the tone and the cage with something negative; the squeaking mouse taught them that the tone predicted distress. When the researchers tried the experiment again, this time with mice from a genetically different strain that is less social, they found that the mice didn’t show any response to the tone once inside the cage. In other words, they didn’t respond to the other mouse’s distress.
“The core of empathy is being able to have an emotional experience and share that experience with another,” says University of Wisconsin-Madison graduate student Jules Panksepp, who worked on the study. “Deficits in empathy are frequently discussed in the context of psychiatric disorders like autism. We think that by coming up with a simplified model of it in a mouse, we’re probably getting closer to modeling symptoms of human disorders.”