Jonah Lehrer describes an fMRI experiment published in Nature by Tricomi, Rangel, Camerer, and O’Doherty. Subjects were first randomly assigned to be rich or poor and given an endowment accordingly. Then they were put in the scanner.
…the scientists found something strange. When people in the “rich” group were told that a poor stranger was given $20, their brains showed more reward activity than when they themselves were given an equivalent amount. In other words, they got extra pleasure from the gains of someone with less. “We economists have a widespread view that most people are basically self-interested and won’t try to help other people,” Colin Camerer, a neuroeconomist at Caltech and co-author of the study, told me. “But if that were true, you wouldn’t see these sorts of reactions to other people getting money.”
I find it helpful to step back and think through how we can come to conclusions like this. Some time ago, neuroscientists correlated certain brain activity measurements with the state of happiness. They did this either by having the subject report when he was happy and then measuring his brain, or by observing him making choices that, presumably, made him happy and then measuring his brain.
Once we have the brain data we no longer need to ask him whether he is happy or make inferences based on his choices, we can just scan his brain to find out. And that allows us to conclude that the rich are less happy receiving $20 than when the poor get $20.
But still, if we wanted to we could just ask them. We might learn something. What would we do if the subjects responded that in fact they would be happier having the $20 for themselves? Would we conclude that they are lying?
Also we might learn something from just letting them decide for themselves whether to give money to the poor. What would we conclude if we see, as we do indeed see in the world, that they do not? That they don’t understand as well as we do what makes their brain happy?
Either way we have a real problem. Because our original reason for associating the specific brain activity with happiness was based on either believing they are honest about what makes them happy or believing that the choices they make reveal what makes them happy. But now in order to apply what we learned we are forced to reject those same premises.