The impact of a poverty reduction intervention on infant brain activity

Abstract

Early childhood poverty is a risk factor for lower school achievement, reduced earnings, and poorer health, and has been associated with differences in brain structure and function. Whether poverty causes differences in neurodevelopment, or is merely associated with factors that cause such differences, remains unclear. Here, we report estimates of the causal impact of a poverty reduction intervention on brain activity in the first year of life. We draw data from a subsample of the Baby’s First Years study, which recruited 1,000 diverse low-income mother–infant dyads. Shortly after giving birth, mothers were randomized to receive either a large or nominal monthly unconditional cash gift. Infant brain activity was assessed at approximately 1 y of age in the child’s home, using resting electroencephalography (EEG; n = 435). We hypothesized that infants in the high-cash gift group would have greater EEG power in the mid- to high-frequency bands and reduced power in a low-frequency band compared with infants in the low-cash gift group. Indeed, infants in the high-cash gift group showed more power in high-frequency bands. Effect sizes were similar in magnitude to many scalable education interventions, although the significance of estimates varied with the analytic specification. In sum, using a rigorous randomized design, we provide evidence that giving monthly unconditional cash transfers to mothers experiencing poverty in the first year of their children’s lives may change infant brain activity. Such changes reflect neuroplasticity and environmental adaptation and display a pattern that has been associated with the development of subsequent cognitive skills.

Long-Term Effects of Local-Area New Deal Work Relief in Childhood on Educational, Economic, and Health Outcomes Over the Life Course: Evidence From the Wisconsin Longitudinal Study

“…Growing evi dence points to pov erty costs regard ing chil dren's neuro en do crine func tion, early brain devel op ment, and cog ni tive abil ity. Results from a ran dom ized con trol trial showed that reg u lar cash trans fers given to low-income fam i lies increased infant brain activ ity at age 1 (Troller-Renfree et al 2022). Poverty has been found to be asso ci ated with smaller white and cor ti cal gray mat ter and hippo cam pal and amyg dala vol umes in child hood (Luby et al 2013).…”

Examining the Role of Socioeconomic Status and Maternal Sensitivity in Predicting Functional Brain Network Connectivity in 5-Month-Old Infants

“…SES is also associated with functional connectivity levels for several brain networks, including the default mode network, sensorimotor network, and brain circuits connecting the prefrontal cortex to deeper brain structures like the striatum and amygdala, within the first 6 months of life (Gao et al, 2015;Turesky et al, 2019;Ramphal et al, 2020). Beyond these correlational findings, poverty reduction interventions also suggest a causal role in the associations between SES and brain development (Troller-Renfree et al, 2022). For example, when low-income families were randomly assigned to receive either large or nominal monthly cash gifts shortly after giving birth, infants in the high-cash group exhibited greater EEG power in higher-frequency bands (beta and gamma) compared to infants in the low-cash group a year later, although these differences did not survive multiple comparisons.…”

Road to Equity in Brain Health

“…Results from the Baby's First Years trial, in which 1000 low-income mothers were randomized to receive either large or nominal monthly cash gifts shortly after delivery, provides experimental evidence that increasing resources for poor mothers improves their children's brain health. 5 Electroencephalographic brain activity at 1 year showed more power in high-frequency bands, a pattern associated with development of subsequent cognitive skills, among infants whose mothers received larger gifts. These changes likely reflect neuroplasticity and environmental adaptation.…”