Does reducing poverty help build children’s minds?

An extensive clinical trial will provide some answers
Woodleywonderworks,, CC BY 2.0
Woodleywonderworks,, CC BY 2.0

Poor children tend to be less healthy, achieve less and exhibit more problem behaviors than children reared in more affluent families. And when they grow up, poor children earn less, suffer worse health and are more likely to commit crimes and have non-marital births than their more fortunate peers. But correlation is not causation. Is poverty per se responsible for these differences, or is it something else about poor children, their families or their communities that produces these differences?

These are the kinds of questions that have kept me up at night over much of my career. Answering them is of scientific interest but also vital for policy discussions surrounding social programs. In the United States, politicians argue over whether poverty is really the central issue for poor children. As a result, debates over poverty policy are often framed in terms of whether these policies trap parents into lives of dependence rather than whether they might help children attain more productive and healthy lives.

Only a random-assignment “clinical trial” can provide the needed evidence to answer these questions and, with the help of funding from the Jacobs Foundation Research Prize that was awarded to me in 2013, we are on the verge of launching such a trial. I have assembled a dream team of neuroscientists, economists and developmental psychologists to develop the first-ever randomized controlled trial to determine whether unconditional cash payments have a causal effect on the cognitive, socio-emotional and brain development of infants and toddlers in low-income U.S. families.

“If family poverty reduction indeed shapes early brain development and cognitive functioning, it is important to identify the family processes that help pave the way.”

We plan to recruit 1,000 poor mothers of infants from four diverse U.S. communities and provide them with monthly cash payments for the first 40 months of their children’s lives. Parents in the experimental group will receive $333 per month ($4,000 per year), while parents in the control group will receive a nominal monthly payment of $20.

In order to understand the impacts of the added income on children’s cognitive and behavioral development, we will assess treatment/control group differences at age 3 on measures of cognitive, language, memory, self-regulation and socio-emotional development. In order to understand the impacts of added income on children’s brain functioning at age 3, we will assess, during a lab visit, treatment/control group differences in measures of brain activity.

How could poverty reduction have an impact on a child’s brain development?

If family poverty reduction indeed shapes early brain development and cognitive functioning, it is important to identify the family processes that help pave the way. Social scientists have studied two complementary pathways by which low family incomes shape the context of child rearing.

First, additional resources enable parents to buy goods and services for their families and children that support cognitive development. These include higher-quality housing, nutrition and non-parental child care; more cognitively stimulating home environments and learning opportunities outside of the home; and, by reducing or restructuring work hours, more parental time spent with children. Measures of these features of the child’s environment will be collected during an in-home interview when the child is 2 years old.

Second, additional economic resources may reduce parents’ own stress and improve their mental health and cognition. This may allow parents to devote more positive attention to their children, leading to a more predictable family life, less conflicted relationships, and warmer and more responsive interactions.

Research suggests that warm and responsive caregivers are able to help children regulate their stress responses. This reduces the likelihood that children will experience the kind of prolonged activation of their stress response systems that has been linked to compromised neural development in the areas of the brain that support memory, executive functioning and socioemotional processing. Enhanced family income may also create more enriching and less stressful family environments by reducing the cognitive load that parents face. Studies show that conditions of scarcity place demands on parents’ limited cognitive resources, directing attention to some problems at the expense of others. Measures of maternal stress, mental health and cognition will also be collected.

A successful pilot study demonstrates the feasibility

Will our plans work? To answer that key question, in June 2014 we launched a pilot study of 30 poor mothers of infants born at New York Presbyterian Hospital to assess our proposed recruitment and payment procedures and pilot data collection to inform the development of final survey data instruments and home assessments.

The thirty mothers who participated in the baseline survey indicated a willingness to be contacted for future data collection, and agreed to be assigned at random to one of two groups, one receiving a larger monthly cash payment, the other only a nominal amount. The pilot sample was largely African American and Hispanic.

When their children were 12 months old, 27 of the 30 mothers participated in an interview that included an in-home assessment of family expenditures, routines and time use, parent stress and parenting practices, and child care arrangements. Bearing in mind the very small sample size (13 treatment and 14 control mothers), substantial and, in a few cases, statistically significant differences were found favoring the treatment group, which showed a reduction in household chaos as well as increased mother-child learning activities and child-care expenditures. The pilot study demonstrated the feasibility of conducting this research on a much larger scale.

Our ambitious project is expensive. The cost of respondent payments alone will exceed $7 million, while research costs will total a little more than that. We have raised much of this money and, with the help of several other foundations and private philanthropists, hope to begin recruiting mothers in the middle of 2017.

The research team for the project includes neuroscientist Kimberly Noble, MD, PhD, economist Lisa Gennetian, PhD and developmental psychologists Katherine Magnuson, PhD and Hirokazu Yoshikawa, PhD.


Duncan, G. J., Magnuson, K., & Votruba-Drzal, E. (2014). Boosting family income to promote child development. The Future of Children, 99-120. doi: 10.1353/foc.2014.0008

Mullainathan S, Shafir E. 2013. Scarcity: Why Having Too Little Means So Much. New York: Times Books, Henry Holt and Company