How does income affect childhood brain development? | Kimberly Noble

The Link Between Family Income and Brain Structure

In this section, the speaker discusses a study that examined the brains of over 1,000 children and adolescents to determine if there is a link between family income and brain structure.

Family Income and Cortical Surface Area

• The study found that family income was associated with the cortical surface area across nearly the entire surface of the brain.

• Regions that support language skills, vocabulary, reading, as well as impulse control were particularly pronounced in their association with higher family income.

• The link between family income and children's brain structure was strongest at the lowest income levels.

Variability in Brain Structure

• There was tremendous variability from one child to another.

• Growing up in poverty is certainly a risk factor for a smaller brain surface but it does not mean an individual child's family income can predict what their particular brain would look like.

Impact on Children Living in Poverty

• Children living in poverty are more likely to struggle with cognitive skills such as language skills like vocabulary and reading as well as impulse control.

• A child living with poverty is likely to perform worse on tests of language and impulse control before they even turn two.

Dollar for Dollar: How Small Differences in Family Income Make a Big Difference

In this section, the speaker explains how small differences in family income can have proportionately greater differences in brain structure among disadvantaged families.

Proportionate Differences

• Relatively small differences in family income were associated with proportionately greater differences in brain structure among the most disadvantaged families.

• An extra $20,000 for a family earning $150,000 a year would certainly be nice but probably not game-changing. However, an extra $20,000 for a family only earning $20,000 a year would likely make a remarkable difference in their day-to-day lives.

The Link Between Family Income and Brain Structure is Independent of Age, Sex and Race

In this section, the speaker explains that the link between family income and brain structure is independent of age, sex and race.

Independence from Demographic Factors

• The link between family income and children's brain structure didn't depend on the children's age, sex or race/ethnicity.

Conclusion: Growing Up in Poverty Should Not Determine Your Future

In this section, the speaker concludes by emphasizing that growing up in poverty should not determine one's future.

Cognitive Scores

• By the time two kids are ready to start kindergarten, the child living in poverty is likely to have cognitive scores that are 60% lower than those of the other child.

• A child living in poverty will be five times more likely to drop out of high school. If she does graduate high school she'll be less likely to earn a college degree.

• By the time those two kids are 35 years old if the first child spent her entire childhood living in poverty she is up to 75 times more likely to be poor herself.

Hope for Change

• It doesn't have to be that way.

Neuroplasticity and Child Development

This section discusses the concept of neuroplasticity and how it can help children from disadvantaged backgrounds overcome differences in brain structure.

The Brain is Not Destiny

• Neuroplasticity means that differences in brain structure do not doom a child to low achievement.

• If a child's brain can be changed, then anything is possible.

Importance of Early Intervention

• Disparities in child development emerge early, sometimes when kids are just toddlers.

• Focusing all policy efforts on formal schooling may be starting too late.

Changing Children's Experiences

This section explores different experiences associated with growing up in poverty that may be targeted to promote brain development and learning outcomes for kids.

Home Language Environment

• Kids from more advantaged backgrounds hear an average of 30 million more spoken words in the first few years of life compared to kids from less advantaged backgrounds.

• Kids who experience more back-and-forth, responsive conversational turns tend to have a larger brain surface responsible for language and reading skills.

• Teaching parents to have more conversations with their children could promote brain development and improve language and reading skills.

Other Experiences Associated with Poverty

• Growing up in poverty is associated with many experiences such as nutrition, access to health care, exposure to second-hand smoke or lead, experience of stress or discrimination.

• There are high-quality interventions that try to change children's experiences but it can be challenging, labor-intensive, costly and patronizing for scientists to tell families what they need to change for their child to succeed.

Can Giving Money to Families in Poverty Improve Child Development?

In this talk, Kimberly Noble discusses the Baby's First Years study, which aims to test whether poverty reduction causes changes in children's brain development. The study involves recruiting 1,000 mothers living below the federal poverty line and giving them an unconditional monthly cash gift for the first 40 months of their children's lives.

Study Design

• The Baby's First Years study is a randomized study involving economists, social policy experts, and neuroscientists.

• The study recruited 1,000 mothers living below the federal poverty line shortly after they gave birth in American hospitals.

• All mothers receive an unconditional monthly cash gift for the first 40 months of their children's lives.

• Mothers are randomized to receive either a nominal monthly cash gift or several hundred dollars each month.

Goals of the Study

• The goal of the study is to test whether reducing poverty causes changes in children's cognitive, emotional, and brain development in the first three years of life.

• If successful, results from this work will inform debates about social services that have the potential to affect millions of families with young children.

Potential Impact

• Reducing poverty may not be the only factor affecting child development but it may be one that can be easily addressed from a policy perspective.

• If reducing poverty leads to meaningful policy changes then a young child born into poverty today may have a much better shot at a brighter future.