Thursday, July 13, 2017
Mike Mariani - The neuroscience of inequality: does poverty show up in children's brains?
There is increasing evidence that growing up poor diminishes the physical development of a child’s brain.
Dr Kimberly Noble’s laboratory at Columbia University in New York looks like your typical day-care centre – save for the team of cognitive neuroscientists observing kids from behind a large two-way mirror. The Neurocognition, Early Experience and Development Lab is home to cutting-edge research on how poverty affects young brains, and I’ve come here to learn how Noble and her colleagues could soon definitively prove that growing up poor can keep a child’s brain from developing. 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’ve seen increasing evidence that poverty itself – and not factors like nutrition, language exposure, family stability, or prenatal issues, as previously thought – may diminish the growth of a child’s brain. Now she’s in the middle of planning a five-year, nationwide study that could establish a causal link between poverty and brain development – and, in the process, suggest a path forward for helping our poorest children.
It’s 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 – to trace the long-standing correlation between socioeconomic status and academic performance back to specific parts of the brain. “There has been decades of work from social scientists, looking at socioeconomic disparities in broad cognitive outcomes – things like IQ or high-school graduation rate,” Noble says. “But there’s no high-school graduation part of the brain.”
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.