Oct. 28 (Bloomberg) -- Poverty and lack of nurturing in early life may have a direct effect on a child’s brain development, according to a study that found smaller brain volumes in poor, neglected children.
The study of brain scans, published today in JAMA Pediatrics, found children living in poverty without adequate nurturing had smaller hippocampus, a brain region linked to learning and memory, than those who weren’t poor or neglected. Poor children, even if not neglected by parents, were found to have less gray matter, which is linked to intelligence; less white matter, which helps transmit signals; and smaller amygdala, an area key to emotional health.
The study adds to previous research suggesting the stress of living in poverty in childhood can have lifelong effects on learning and emotional health, said Charles Nelson, who wrote an accompanying editorial in the journal. Today’s findings brings researchers closer to better understanding how experience shapes biology, he said.
“This work adds to a growing body of evidence that early life events powerfully shape not only the course of child development but also adult development,” said Nelson, a professor of pediatrics and neuroscience at Harvard Medical School in Boston, in an Oct. 25 e-mail. “It adds to the literature showing that early adversity can have life-long effects on both psychological and physical development.”
A study published last week in the journal Proceedings of the National Academy of Sciences by researchers from the University of Denver showed using brain imaging that adults who were poor as children were less able than other participants to minimize their emotional reactions to negative images. A second paper the same day by researchers from the Weill Cornell Medical College in New York found that children who had lived in an orphanage were more anxious than those who hadn’t.
In today’s study, researchers examined 145 children, age six to 12, who had participated in a larger preschool depression study and underwent magnetic resonance imaging, or MRI scans. Some in the study were healthy, others were depressed or had disorders like attention-deficit hyperactivity disorder.
The study found that while poverty did affect the brain, the differences in the hippocampus in poor children was a lack of care by parents. The study also showed that parents living in poverty who were rated as poor nurturers were more stressed and less able to nurture their children during a caregiver exercise.
The brain findings were consistent even after controlling for the children’s depression and the other disorders, said lead study author Joan Luby.
The study “gives us a clue to how to maybe prevent some of the deleterious effects of poverty on childhood brain development,” Luby, a professor of psychiatry at Washington University School of Medicine in St. Louis, said in a telephone interview today. “There’s a startlingly high percentage of children in the nation and worldwide that are facing poverty. This study gives us a clue as to how we can focus our preventive interventions by focusing on parenting support or caregiver support.”
Parents living in poverty may be less emotionally responsive to their children because they may work two jobs, have to regularly try to find money for food or they live in an unsafe environment, she said. Children who are poor also experience stress including moving to a new house, changing schools or parents who fight regularly.
--Editors: Angela Zimm, Bruce Rule