With its bright colours, anthropomorphic animal motif and nautical-themed puzzle play mat, Dr Kimberly Noble\u2019s laboratory at Columbia University in New York looks like your typical day-care centre \u2013 save for the team of cognitive neuroscientists observing kids from behind a large two-way mirror.<\/p>\n
The Neurocognition, Early Experience and Development Lab is home to cutting-edge research on how poverty affects young brains, and I\u2019ve come here to learn how Noble and her colleagues could soon definitively prove that growing up poor can keep a child\u2019s brain from developing.<\/p>\n
Noble, a 40-year-old from outside of Philadelphia who discusses her work with a mix of enthusiasm and clinical restraint, is among the handful of neuroscientists and pediatricians who\u2019ve seen increasing evidence that poverty itself \u2013 and not factors like nutrition, language exposure, family stability, or prenatal issues, as previously thought \u2013 may diminish the growth of a child\u2019s brain. Now she\u2019s in the middle of planning a five-year, nationwide study that could establish a causal link between poverty and brain development \u2013 and, in the process, suggest a path forward for helping our poorest children.<\/p>\n
It\u2019s the culmination of years of work for Noble, who helped jump-start this fledgling field in the early 2000s when, as a University of Pennsylvania graduate student, she and renowned cognitive neuroscientist Martha Farah began exploring the observation that poor kids tended to perform worse academically than their better-off peers. They wanted to investigate the neurocognitive underpinnings of this relationship \u2013 to trace the long-standing correlation between socioeconomic status and academic performance back to specific parts of the brain.<\/p>\n
\u201cThere has been decades of work from social scientists, looking at socioeconomic disparities in broad cognitive outcomes \u2013 things like IQ or high-school graduation rate,\u201d Noble says. \u201cBut there\u2019s no high-school graduation part of the brain.\u201d<\/p>\n
Prior to their study, scientists had never investigated the specific cognitive tasks (face learning, picture learning, vocabulary tests) in which poor children underperformed, let alone mapped out how their brain structure and development might differ. So in 2005, Noble and Farah, along with University of Pennsylvania colleague Frank Norman, recruited 60 children from Philadelphia public-school kindergartens (30 middle-class kids and 30 who were at or just above the poverty line) and gave them a series of cognitive tests, each of which has been linked to a specific brain circuit.<\/p>\n
Among other things, the tests measured language development and executive functioning \u2013 the set of mental processes responsible for working memory, reasoning and self-control. It turned out that low-income children performed moderately to significantly worse than their middle-class peers in both areas.<\/p>\n
The results, which Noble and Farah reported in a 2005 paper, were the beginning of what they call a \u201cneurocognitive profile\u201d of socioeconomic status and the developing brain. Farah, Noble and other scientists soon began using magnetic resonance imaging (MRI) scans to examine the brains of children across the socioeconomic spectrum.<\/p>\n
The results were striking. In one study, Farah looked at 283 MRIs and found that kids from poorer, less-educated families tended to have thinner subregions of the prefrontal cortex \u2013 a part of the brain strongly associated with executive functioning \u2013 than better-off kids. That could explain weaker academic achievement and even lower IQs.<\/p>\n
In 2015, Noble co-authored the largest study to date. Using MRI, researchers examined 1,099 children and young adults, and found the brains of those with higher family income and more parental education had larger surface areas than their poorer, less-educated peers. The strongest correlation came in brain regions associated with language and executive functioning.<\/p>\n
What\u2019s more, the data indicated that small increases in family income had a much larger impact on the brains of the poorest children than similar increases among wealthier children. And Noble\u2019s data also suggested that when a family falls below a certain basic level of income, brain growth drops off precipitously. Children from families making less than $25,000 suffered the most, with 6% less brain surface area than peers in families making $150,000 or more.<\/p>\n
A few months later, another large study co-authored by Seth Pollak, a child psychologist at the University of Wisconsin-Madison, found strong ties between household income and the volume of grey matter in the frontal lobe, temporal lobe and hippocampus.<\/p>\n
Children from households below the federal poverty line ($24,250 for a family of four in 2015) had 8 to 10% less grey matter in these critical regions. And even kids whose families were slightly better off \u2013 incomes of one-and-a-half times the federal poverty level \u2013 had 3 to 4% less grey matter than the developmental norm. In Pollak\u2019s study, many of the poor parents were highly educated, indicating the \u201cmaturational lags\u201d their children suffered from were a direct result of the circumstances of poverty.<\/p>\n
The policy implications are immense. If the data holds, simply moving a family\u2019s income out of poverty might be enough to get that child much closer to cognitive developmental norms. And while we don\u2019t yet know whether, or how much, these brain disparities persist into adulthood, this research \u2013 combined with past work demonstrating that people raised in poverty end up doing worse financially and suffering greater health problems than their more-affluent contemporaries over the course of their lifetimes \u2013 suggests they probably have lifelong effects.<\/p>\n
These studies indicate it isn\u2019t one specific factor that\u2019s solely responsible for diminishing brain growth and intellectual potential, but rather the larger environment of poverty.<\/p>\n
\u201cI would say we have strong correlational evidence at this point, but we don\u2019t really have the causal evidence yet,\u201d Noble says. And that\u2019s where her upcoming study fits in.<\/p>\n
To prove causality, she and several other researchers \u2013 Greg Duncan, an economist at the University of California-Irvine; Katherine Magnuson, a social-policy expert at the University of Wisconsin-Madison; Lisa Gennetian, a New York University economist; and Hirokazu Yoshikawa, an NYU psychologist \u2013 are developing a nationwide study that will include 1,000 low-income families. The families will be divided into two groups: one will receive a cash payment of $333 a month ($4,000 a year), and the other $20 a month.<\/p>\n
As Noble mentioned in an op-ed in the Washington Post, past research has shown that an increase of $4,000 in family income during the first years of a child\u2019s life is associated with greatly improved outcomes in adult earnings, employment and physical health. Based on their findings, Noble and her collaborators believe it is also enough to significantly improve brain development.<\/p>\n
The new study will take five years to complete, with payments beginning shortly after the mothers give birth and lasting until the children turn three years old. Researchers will collect data through interviews with the mothers at 12 and 24 months; after the children turn three, they will visit the participating labs where researchers will test their language, memory, executive functioning and social and emotional development. They will also measure the development of their brain circuitry through electroencephalography (EEG) \u2013 infants are too young to be exposed to the long, uncomfortable experience of being inside an MRI machine.<\/p>\n
If the children who receive the modest stipend show healthier brain activity and perform better on cognitive tests than those in the control group, Noble and her colleagues will have the first causal evidence linking dire poverty to neural development. She hopes to launch the $16 million study by early 2018.<\/p>\n
Her team\u2019s funding proposal could have major implications for \u201cincome-enhancement policies\u201d in the US \u2013 including the earned income tax credit, the child tax credit, and temporary assistance for needy families, all of which put money directly in the pockets of poor families.<\/p>\n
\u201cAlthough income may not be the only factor that determines a child\u2019s developmental trajectory,\u201d Noble wrote in a March article for Scientific American, \u201cit may be the easiest one to alter from the standpoint of implementing policy \u2013 a down-payment of sorts to promote the health of a growing child\u2019s brain.\u201d<\/p>\n
At least, that\u2019s what researchers were hoping before the presidential election. As Martha Farah told me, Hillary Clinton has been interested in using neuroscience to better understand child poverty ever since she was first lady.<\/p>\n
\u201cI would expect her to have been very proactive on this topic, both trying to support the research and also looking for all kinds of ways \u2013 neuroscience-related and otherwise \u2013 to support the development of kids in poverty,\u201d Farah said. \u201cIt\u2019s really a shame for this field that she\u2019s not our next president.\u201d<\/p>\n
As for President Donald Trump: \u201cIt doesn\u2019t seem like that would be his top priority,\u201d according to Farah. Indeed, his budget proposes drastic cuts to Medicaid and other safety net programmes. Luckily, a lot of the papers being published on how poverty affects developing brains are using data sets from other studies.<\/p>\n
\u201cBasically, this work is going forward without much in the way of focused federal funding,\u201d Farah added. This means the research can continue to thrive, even under a federal government unconcerned with the potential causal relationship between child poverty and stunted brain growth.<\/p>\n
Of course, much of the power to convince politicians and move the needle in policy circles hinges on the outcome of Noble\u2019s upcoming study. We need to know \u201cthat if we gave people more money, kids\u2019 brains would look different\u201d, says Russ Whitehurst, a senior fellow at the Brookings Institution\u2019s Center on Children and Families.<\/p>\n
Besides influencing the debate over tax credits and cash entitlements for poor families, clearing that bar of causation could help transform the way Americans think about the social safety net in a country where more than one in five kids \u2013 15 million in total \u2013 live below the federal poverty line.<\/p>\n
Source:\u00a0theguardian.com<\/a><\/p>\n