Scientists have known for a long time that low-income children have smaller brains than their more economically secure peers. And they’ve suspected that limited access to health care is at least partially responsible. But according to new research, the culprit may actually be excess stress that interferes with immune system function, damages cells and DNA, causes inflammation (which, generally speaking, is never a good thing). The results: less white and gray matter and a smaller hippocampus and amygdala, two parts of the brain that are involved with, emotion, learning, and memory.
“Generally speaking, larger brains within a certain range of normal are healthier brains,” said Joan Luby, a professor of child psychiatry at St. Louis’s Washington University School of Medicine, and the lead author of the study. “Having a smaller brain within a certain range of normal is generally not healthy. It’s associated with poorer outcomes,” Luby said in an interview with Reuters Health.
Fortunately, there may be a relatively easy way to eliminate some of the brain shrinkage—specifically in the hippocampus and amygdala. Good parenting. Yep. Lots of warm, emotionally supportive parent-child relationships.
Sounds kind of crazy, doesn’t it? But that’s what Luby and her Washington University colleagues when studying the brains of preschoolers over several years. The researchers used MRIs to track the size of the children’s brains. The connection between poverty and brain size didn’t surprise them much—other studies have reached similar conclusions. But part way through the study, they decided to evaluate the kids’ parents as well. And they came up with an interesting way to do that.
They gave each child a tantalizingly wrapped gift but told them they couldn’t open it until their parent, who was within view, was finished filling out a long form. Predictably, the preschoolers—who are not known for their patience or ability to delay gratification—started bugging their parents.
Luby and her colleagues then monitored the parents’ reaction on a scale that ran from “supportive” (praising the child for waiting patiently) to “hostile” (threatening to punish the child). Surprisingly, when matching up the parents’ behavior to their child’s brain size, it became clear that the kids with the supportive parents had a hippocampi and amygdalae that were completely normal. “The effects of poverty on hippocampal volume were mediated by caregiving support,” the study said. There was no connection between supportive parenting and other brain areas.
What does all this mean to us? I think the message here is that everything we do as parents can have an effect on our children. And although we all experience stress, warm, emotionally supportive parenting can help our kids get through almost anything.
The study, “The Effects of Poverty on Childhood Brain Development: The Mediating Effect of Caregiving and Stressful Life Events,” was published in the journal JAMA Pediatrics. You can read an excerpt here: