Are Acts of Kindness Random?

Some of us are inclined to be charitable— especially as we age

A hypothetical: You’re walking along when you spot a $20 bill on the sidewalk. Do you pocket it? Or give it to the charity on the corner?

Your answer should indicate whether you’re more concerned about others or yourself. But it doesn’t, necessarily. You might lie just to look good: “Charity, of course!” Even if you truly would donate the money, you might do it out of self-interest—say, to appear compassionate. In fact, you might not even know why you’d give up the $20 in that situation.

Given human nature, it’s hard for scientists to get at the truth of a seemingly straightforward question: Is it possible to care wholly and completely for the welfare of others—or is self-interest always involved?

Ulrich Mayr found an answer, by asking a source that doesn’t mislead: the human brain.

The head of the psychology department  (above right) teamed with economics professor Bill Harbaugh and psychology graduate student Jason Hubbard to test whether there is such a thing as “pure altruism”: acts of kindness done not for our own benefit but only for the benefit of others. The tests included MRI imaging that showed—at the neural level—whether subjects’ brain pathways were excited more by charity or self-interest.

The result was a resounding “yes”—some people give solely to help others. Even better, Mayr said, is the possibility that this kindness can be learned.

Q: You could study any number of human behaviors. Why altruism?

Ulrich Mayr: Well, it touches on a very basic question, doesn’t it? Mainly, whether people are good or bad. Scientists have historically tried to answer that question through a more specific one—the willingness of people to share their hard-earned resources with others in need. But that’s a tough nut to crack. People give away money for all sorts of reasons—to get their name on a building or get something in return or just to make people think that they have great character. You can’t get a good answer by simply asking people, “Why do you give?” You have to trust your subjects to tell you the truth, but they don’t always do so, so you’re in a bind there.

Q: Your tests involved real money. Walk us through them.

UM: First, we asked people repeated questions about how much money they wanted to give to charities and how much they wanted to keep. This was actual money paid to them for being in the study, so every dollar they didn’t give away they could take home. We kept a tally of how much money they were willing to give away over the course of the experiment.

Next, we ran them through personality questionnaires—how nice they are to others, how often they give to charity, how much they volunteer, that sort of thing. We wanted a broad understanding of their tendencies to be selfless or altruistic.

Q: Why would someone tell you if they’re actually selfish and greedy?

UM: That’s exactly the problem. Both the personality questionnaire and the giving-away-money exercise are subject to lying—you don’t really know what’s driving people’s responses, altruism or self-interest.

But the brain doesn’t lie. So for the third piece, we placed people in an MRI scanner and honed in on the “reward” areas of the brain that respond whenever something good happens to you—it could be money, good food or sex, for example. On a monitor, they watched transfers of $20 going to charities or to themselves. But they had no control over whether the money went to them or the charity. That’s important. In this situation, all of the non-altruistic motives fall away—you can’t influence anything, so you can’t engage in self-interest.

We observed that for some people, the reward areas respond when money comes to them—no big surprise there. But for some people, it responds more strongly when money goes to the charities. This is a measure of pure altruism—it cannot be easily faked.

Q: Why did you measure altruism three ways? Why not just rely on the brain imaging?

UM: The questionnaires and behavior tests are the traditional ways that we have tried to measure altruism, but we didn’t know whether they were actually getting at that behavior. By adding brain imaging, we found that all three are truly measuring altruism—there was consistency among the scores indicating a person’s level of altruism, across the three methods.

Q: Explain what happened with tests involving “the people in the white lab coats.”

UM: This was an interesting little tidbit. We asked people to make decisions whether to give to charity under two different conditions—one in which their setting was completely private and they knew no one was watching, and one where they were watched by people in a control room in white lab coats. People in the latter condition gave considerably more.

This shows that those self-interest motivations are also there, even in the people who are also very benevolent. But these reactions can be isolated and they don’t
affect the assessment of pure altruism.

Q: What did you find regarding older subjects?

UM: We found that a 60-year-old is about twice as likely to give money away to charity as a 25-year-old.

It’s always been known that older people give quite a bit more money, although psychologists are still trying to figure out why. Our study confirms that older people give more but it’s not because they have more money, or feel more pressure to give, or are more inclined to follow expected social norms. There is a “strengthening” of this general tendency to be benevolent.

Q: Why do you think older people are more charitable?

UM: One possibility is that it’s purely biological—something switches on in the brain that makes us more altruistic. I find that very implausible.

If you assume that’s unlikely, it has to be something that people experience—something about the way that older people construe the world that is different in younger adults. If that is the case then it’s something, in principle, that can be learned.

It’s important to note that the purpose of the reward areas in the brain is not to make us happy—that’s not their evolutionary purpose. Their purpose is to signal to the brain an action that is worth repeating. It’s a learning mechanism—it drives what the brain needs to encode, to memorize, so it can repeat it in the future to get that root sense of reward again.

Q: Do you think it’s possible to teach altruism?

UM: Well, we have shown here that by engaging in altruistic behavior, you get a reward in part of the brain. That should actually strengthen future altruistic behavior. I think it provides a key toward thinking about educational measures that could really drive this reward-related mechanism and strengthen altruistic behavior.

It suggests that it should be possible, maybe through a mild coercion, to get people to actually do good deeds. You could ask your kids to spend a portion of their allowance for a good cause of their choosing, for example. They may experience something they wouldn’t have experienced if you didn’t coerce them, and that’s a way to get that sense of reward. Then, if you’re somewhat lucky, it becomes a self-driving force and you don’t have to coerce them anymore. It becomes a habit.

—Matt Cooper