Marsh Explains the Science Behind Donating Kidneys to Strangers

The Park Street Corporation Speaker Series held its first event for this year’s theme of “Health, Humanity, and Ethics: the Common Good” on Thursday evening. Abigail Marsh, an associate professor of psychology, neuroscience, and cognitive science at Georgetown University, presented “The Altruistic Brain: Making the Choice to Help,” which explored extraordinary altruism through the research on kidney donors.

Marsh began by telling the story of Harold Mintz, who in 2000 became the first person to donate his kidney to a complete stranger—Gennet Belay. 

When Mintz initially asked organ donor authorities if he could donate his kidney,  he was denied. It used to be illegal to donate a kidney to a stranger, as this type of action was thought to be pathological or insane, according to Marsh. Later, a pilot program for altruistic kidney donors asked Mintz to participate.

Since then, over 2,000 Americans have made similar donations, Marsh said.

Marsh said that the question of why someone would voluntarily do this is difficult to explain, as it is a completely selfless act. She began to answer this question by showing an interview with Mintz.

Just as a person would donate their kidney to their parents, siblings, or friends, they should also be capable of donating to a complete stranger to help them alleviate their pain and suffering, he said in the interview.

“So this is pretty typical of altruistic kidney donors’ explanations,” Marsh said. “They boil down to some variation of ‘I wanted to help somebody who’s suffering. It just seemed like the right thing to do.’ And this has been the most amazing thing I’ve learned in working with kidney donors is that it seems like the obvious thing to do.”

Marsh said she thought that, as people learned more about kidney donations, they would also become more likely to donate to a stranger. 

Yet her research showed that even when people obtained detailed information about the issue, only about 17 percent said they would be more willing to consider an altruistic donation. Marsh said she realized that information was not the motivating factor and drew a parallel to smokers who are aware of the negative health effects.

Marsh then turned to the 17 percent for whom the information made a difference—the altruistic donors.

She compared their reaction to the “social discounting curve,” or the question of taking $150 for yourself versus splitting it with the closest person to you in your life. For most people, they would prefer to split it with the person closest to them, but if the question is splitting with the 100th closest person in your life—practically a stranger—most would keep the $150, Marsh said. 

This is because resources don’t have the same value when shared with strangers, according to Marsh. When altruistic kidney donors are faced with this question though, they value the 100th person as much as the average person values their 20th person in their life—”extreme altruists” don’t view strangers as strangers, but as friends, she said.

“So the question was, does this choice that the kidney donors made reflect the idea that they do not discount the value of this stranger’s welfare as much as the average person?” Marsh asked. “And you can see that the answer is clearly yes.”

Scans of altruists’ brains show that they really do feel the pain of strangers, matching the brain scans of people who see their loved ones in pain, according to Marsh. Further testing would require testing empathy, which would be extremely difficult to study. So Marsh turned to the opposite of people with altruism—people with psychopathy.

Psychopathy is a condition marked by persistent antisocial behavior and reduced empathy and concern for others suffering because of neural abnormalities, according to Marsh.

“People who are psychopathic are selectively impaired in even being able to recognize when somebody else is afraid.” Marsh said. “If you can’t recognize when somebody’s afraid, why would you care about causing that pain in people, and why would you be motivated to alleviate their pain?

Marsh said that if humans were fundamentally selfish, there wouldn’t be such a thing as psychopathy: The fact that there is a group of people set apart and diagnosed as clinically lacking compassion means that everyone else has the capacity to care about others. 

Marsh has begun measuring “capacity to care” with a sliding scale, with altruism representing the inverse of psychopathy, and her research has supported that there is no one human nature, as people differ in their care and compassion.

Sometimes people refer to those who help others as saints or guardian angels because it’s hard to imagine this kind of goodness coming out of a natural process, Marsh said. But her findings suggest that this motivation does in fact come from basic biological processes that most people share in varying degrees. 

“The choice to help is not a supernatural phenomenon,” Marsh said, “It is completely natural.”

Featured Image by Jess Rivilis / Heights Staff