>> reporter: piff is part of a team, headed by dacher keltner, that studies the psychological effects of both absolute and relative poverty and wealth. >> we can also ask, do people believe in this dream? >> reporter: what they're studying is economic inequality, which, as our viewers probably know, is as high as its been in almost a century in this country. >> there are new data coming out on a daily basis from top laboratories, showing no matter how you look at it, the effects of inequality are pernicious upon things like bullying on school playgrounds; the quality of your physical health; how you handle disease. >> reporter: what's somewhat surprising, says keltner, is that even the haves suffer. >> one of the things that wealth and money does is it comes with a set of values and if you want a deeper ideology, one of them is: generosity is for suckers. and greed is good. but it turns out, there are a lot of new data that show if you're generous, and charitable, and altruistic, you'll live longer; you'll feel more fulfilled; you'll feel more expressive of who you are as a person; yo

stellar's mentor, berkeley psychology professor dacher keltner, says the lab postulated that kids ofher and lower economic status experience the world in very different ways. >> when you grow up in lower class backgrounds and lower class circumstances, there's just more difficulty in your environment; there's more unpredictability; there's more risk; there are more threats and what we've learned from really interesting neuroscience is that humans, in the face of threat, connect to other people. and then complementarily, we thought: you know, if you grow up in a more privileged circumstance, you orient inwards to what's inside of you. and those are two fundamentally different ways of approaching the world. >> reporter: in his own early work, keltner found socio- economic differences in the ability to read facial expressions. >> here's anger. sadness. here's sympathy, or compassion... >> reporter: it turned out those lower down in the economy were better judges of emotional expressions-- expressions rather more subtle than these. >> so given what we found early, we developed a hypothes