CRF Blog

Baby Brains

by Bill Hayes

In Baby Brains, National Geographic reports on the importance of the first year in the development of a baby’s brain.

In the late 1980s, when the crack cocaine epidemic was ravaging America’s cities, Hallam Hurt, a neonatologist in Philadelphia, worried about the damage being done to children born to addicted mothers. She and her colleagues, studying children from low-income families, compared four-year-olds who’d been exposed to the drug with those who hadn’t. They couldn’t find any significant differences. Instead, what they discovered was that in both groups the children’s IQs were much lower than average. “These little children were coming in cute as buttons, and yet their IQs were like 82 and 83,” Hurt says. “Average IQ is 100. It was shocking.”

The revelation prompted the researchers to turn their focus from what differentiated the two groups toward what they had in common: being raised in poverty. To understand the children’s environment, the researchers visited their homes with a checklist. They asked if the parents had at least ten books at home for the children, a record player with songs for them, and toys to help them learn numbers. They noted whether the parents spoke to the children in an affectionate voice, spent time answering their questions, and hugged, kissed, and praised them.

The researchers found that children who received more attention and nurturing at home tended to have higher IQs. Children who were more cognitively stimulated performed better on language tasks, and those nurtured more warmly did better on memory tasks.

Many years later, when the kids had entered their teens, the researchers took MRI images of their brains and then matched them up with the records of how warmly nurtured the children had been at both four and eight years old. They found a strong link between nurturing at age four and the size of the hippocampus — a part of the brain associated with memory — but found no correlation between nurturing at age eight and the hippocampus. The results demonstrated just how critically important an emotionally supportive environment is at a very young age.

The Philadelphia study, published in 2010, was one of the first to demonstrate that childhood experience shapes the structure of the developing brain. Since then, other studies have shown a link between a baby’s socioeconomic status and the growth of its brain. [more]