Monitor - July/August 2015

Psychologist Rosario Ceballo, PhD, grew up poor. Her parents, both immigrants from the Dominican Republic, worked in factories in New York City. One day
when Ceballo was a girl, her mother took her to the factory
where the mother sewed bathing suits in a vast room filled with
row after row of sewing machines. “The family story is that
the foreman said, ‘There’s a sewing machine waiting for you,’
meaning me,” says Ceballo. “My mother said, ‘No, she’s not
going to do this.’”
Ceballo’s mother was right. Ceballo’s grandmother, a
housekeeper who worked for teachers at a private school in New
York City, helped Ceballo get a scholarship to that school for 12
years. Today, Ceballo is a professor of psychology and women’s
studies at the University of Michigan in Ann Arbor and studies
the factors that helped her — and other children — move into
the middle class.

Ceballo is one of many psychologists who are conducting research on ways to help people escape poverty. With 44 percent of American children now living in low-income families, according to the National Center for Children in Poverty, these psychologists are investigating how poverty affects the brain and children’s ability to take advantage of educational opportunities. They’re also exploring how the stress of poverty can lead to heart disease and other life-shortening illnesses. And they’re studying what parents can do to help lift their children out of poverty.

Poverty’s impact on the mind

Poor children’s brains look different from those of their better-off counterparts, according to psychologist Martha J. Farah, PhD, who directs the University of Pennsylvania’s Center for Neuroscience & Society.

Using structural magnetic resonance imaging, Farah and her colleagues have assessed the relationship between socioeconomic status and brain development. In a 2013 study in Developmental Science, they examined socioeconomic status’s impact on the prefrontal cortex. This region of the brain, the researchers explain, is essential for executive function and thus associated with intelligence and academic success. The prefrontal cortex also has a long developmental trajectory and is sensitive to environmental factors, such as stress. In the study, Farah and her colleagues found that parental education — a common measure of childhood socioeconomic status — significantly predicted the thickness of the prefrontal cortex in children’s brains.

Although brain differences may suggest that genetic causes are at work, environmental differences between lower and higher socioeconomic status childhoods are also likely to contribute to the effects we see, says Farah. These include stress, lack of cognitive stimulation, poor nutrition, exposure to lead and other neurotoxins and differences in medical care.

Those brain differences are reflected in children’s working
memory, problem-solving and other executive function skills,
says Farah. Researchers have long known that childhood
socioeconomic status predicts executive function abilities, she
says. What they haven’t known is whether those disparities
change throughout childhood, perhaps with accumulating
stressors widening the gap or further development and
education allowing poor children to catch up.

In a 2015 paper in Developmental Science, Farah and colleagues examined the relationship between socioeconomic status and executive function in data on more than 1,000 children followed longitudinally in a National Institute of Child Health and Human Development study and found that the relationship stayed constant into middle childhood. Consistent with environmental causes, the disparities in socioeconomic status were partly accounted for by children’s access to stimulating toys and books, excursions to visit people and places outside the home and parents who talked a lot with them.

The study also found that as a family’s income grew, so did children’s working memory and planning abilities. Although the evidence is correlational rather than causal, says Farah, genetic differences wouldn’t explain why family fortunes and executive function fluctuate in tandem.

Being poor can also affect the minds of adults, according to research by Princeton psychology and public affairs professor Eldar Shafir, PhD, co-author of the 2014 book “Scarcity: The New Science of Having Less and How It Defines Our Lives.” (See “The psychology of scarcity” in the February 2014 Monitor on Psychology.)

Scarcity — whether it’s a lack of money, time or even food to satisfy a dieter’s hunger — can cause “tunneling,” or over-focusing on one thing to the detriment of other things, says Shafir. For the poor, focusing on immediate financial crises means there’s little “mental bandwidth” left over for other day-to-day tasks, such as overseeing children’s homework or taking medicine on time, let alone building an emergency fund or taking other steps toward financial security.

In fact, says Shafir, poverty can actually impede cognitive functioning. In a paper in Science, he and co-authors studied Indian sugarcane farmers and found that they scored the equivalent of 10 IQ points higher in the post-harvest period — when they are relatively rich — than in the pre-harvest period, when they are poor.

Shafir and his colleagues found the same pattern in shoppers at a New Jersey mall. In a series of experiments also described in the Science paper, they asked shoppers with a diverse range of incomes to ponder scenarios designed to trigger their own financial concerns and then undergo cognitive tests. Rich and poor performed similarly when the scenario involved a small sum, such as a $150 car repair bill. But when the scenario involved high costs, such as a $1,500 repair bill, the poor performed significantly worse.