Photo courtesy of Flickr user Jeff Ruane, under a Creative Commons license.

Poverty hurts a child's chances of getting ahead, of thriving in school, of growing up healthy. It touches the brain and influences the air children breathe. It fundamentally affects where they live and the kind of world they're exposed to.

"We know a lot about how kids experience poverty," says Candice Odgers, the associate director of the Center for Child and Family Policy at Duke University. "That’s been a driving force of research with children — trying to understand the toxic effects of poverty, how they become biologically embedded, how they get under the skin."

We don't know much, though, about a related phenomenon: how kids experience inequality. And new research Odgers has published along with colleagues at Duke, UC Irvine and King's College London suggests some of the answers may complicate policies designed to lift children out of poverty.

In research just published in the Journal of Child Psychology and Psychiatry, they uncovered a surprising result among children in the U.K.: Low-income boys who grow up around wealthier peers have more behavior problems like lying, cheating and fighting than their counterparts who grow up immersed in poverty. That result implies that there may be unintended negative consequences to efforts at creating the kinds of communities where poor and better-off families live side by side.

This research, which draws from a decade-long longitudinal study of twins growing up across Britain, didn't show similar effects for girls. For poor boys, though, the wider the wealth gap between them and their neighbors, the worse their problem behavior, as early as age 5. And this result held even after the researchers tried to control for other family and neighborhood influences that might explain the pattern, like parental behavior and levels of neighborhood cohesion and trust.

Low-income children living alongside more affluent neighbors had higher levels of antisocial behavior than their low-income peers living in concentrated poverty. From the Journal of Child Psychology and Psychiatry, Odgers et. al

This raises a question we've seldom thought to ask about inequality: "What does it mean to be a child embedding in one of these economically mixed communities," Odgers asks, "when you’re on the lowest rung of that ladder?"

One explanation for why boys might get in more trouble in wealthier neighborhoods is that they simply have more opportunity to do so. But Odgers points to another, more compelling theory: Kids living in poverty see themselves — and their prospects — differently when they're surrounded by other children who have more than them.

You may recognize a similar phenomenon at play in the common cliché that "we were poor growing up but we didn't know it." The theory here is that we evaluate the economic distance between ourselves and the people around us, and then we use that assessment to figure out our own relative position in the world. If all the families you know are comparable to yours — whether you're poor or middle-class or well-off — you may view your own standing as typical.

If, however, you're a poor child surrounded by peers with newer clothes, nicer things and more opportunity, that may color how you feel about your own worth and your chances at success.

"A lot of evidence suggests your perceived position matters as much as your objective position," Odgers says.

As as result, she and her co-authors suggest, poor boys may struggle in the "shadow" of the wealth around them. And girls may not experience the same thing because they're often more closely guarded at home by parents, with less exposure to influences beyond the family. Among the non-poor children in the study, the more predictable result appeared: The greater the concentration of neighborhood poverty around them, the worse their antisocial behavior.

Research from Duke University's Center for Child and Family Policy indicates that low-income boys fare worse when growing up in mixed-income neighborhoods. (Duke University)

The researchers found data to conduct this study from the U.K. in part because mixed-income neighborhoods are so much harder to find in the U.S. (England has a longer history of prizing such integration). And so it's not entirely clear if these results would extend to the U.S. as well, especially given that economic segregation here is so closely intertwined with race. Earlier research, though, has found some similar findings about boys' behavior in the U.S.

The questions this research raises, though, about how children experience inequality are certainly relevant here — especially as the gap between rich and poor widens. So, too, are the questions about how we pursue economic integration.

"I wouldn’t want anyone to walk away from these findings and think that this is ammunition against creating economically mixed communities," Odgers says. "There are probably a lot of good reasons, social justice reasons, potentially positive effects on other outcomes."

But, she says, we lack data on many of those outcomes, and these numbers suggest there may be negative effects as well. This research also means that, when we do try to foster mixed-income neighborhoods, we may need to buttress those policies with greater support for kids who discover themselves at the bottom of the income ladder.

The implications of the research for an increasingly unequal country are troubling, too. Across the world's richest countries, Odgers adds, there is a striking relationship between child wellbeing and inequality: