Why some people are wired to help strangers, and what their brains reveal; The Washington Post, January 8, 2026

Cristina Quinn, The Washington Post; Why some people are wired to help strangers, and what their brains reveal

"Abigail Marsh, a professor of psychology and neuroscience at Georgetown University, studies extraordinary altruism — people who jump in to rescue strangers in emergencies or donate a kidney to someone they don’t know. Marsh spoke with Cristina Quinn, host of The Washington Post’s podcast “Try This,” about what her work has uncovered, and what brain science reveals about people who habitually engage in selfless acts. The conversation has been edited for length and clarity...

The group you’ve studied most closely is people who donate a kidney to a stranger. What makes them different?

Genuinely altruistic people are very humble and less selfish than other people. And it turns out that humility and being unselfish go hand-in-hand because if you think that you’re the most special person around, why would you want to help less-special people? And so truly altruistic people do not think of themselves as special.

And when we bring them to our lab, we find differences in their MRI scans. One of the most striking is that altruistic kidney donors tend to have a larger amygdala, a part of the brain critical to processing emotions, particularly fear in others. They are especially sensitive to others’ distress and responding empathically.

In your earlier research, you found the opposite pattern in people with psychopathy?

Yes, we found that the amygdala tends to be smaller in individuals with psychopathic traits. They have difficulty recognizing fear and distress in other people. Most people with psychopathic traits report not feeling fear as often as other people do. And what’s interesting about that is that if you don’t really feel an emotion, it’s very difficult to empathize with it in other people.

So we asked, is altruism the inverse of psychopathy? And it turns out that yes, altruistic kidney donors are more reactive than typical people to the sight of others in distress. And they are relatively better at recognizing other people’s fear, as well."