Daycare's powerful effect on your child's brain

You are the cumulative effect of your life experiences on your brain. As your genetic endowment interacts constantly with the world around you, you’re constantly reshaping your brain in response to your experiences.

Childrens' brains are especially “plastic.” Unsurprisingly, children who attend daycare for years tend to think and behave differently from children who stayed at home during their early childhood. (Evidence below shows that remains true more than a decade later.)

One of the reasons we sent our son to daycare at age 2 is that he was rather shy and, we hoped, would become more outgoing by interacting regularly with teachers and kids his age. That certainly has worked well. He’s much less shy than he was when he began in September 2008. But he has picked up some bad habits from his classmates, several of whom love to shriek at the top of their lungs, for example. Daryl is far more restrained than them, but it’s sometimes clear his classmates are not always a positive influence. Don’t get me wrong. He’s still a great kid. He’ll complain to us that “None of my friends listens to the teacher.” But, on the margins, he has become less shy (good) and less restrained (sometimes good and sometimes bad). His classmates have shaped his brain development.

The effect of daycare on brain development varies with the quality of teachers, class size, and the children’s personalities. But, on average, there’s a clear effect:

At age 15, according to a study being published Friday in the journal Child Development, those who spent long hours in day care as preschoolers are more impulsive and more prone to take risks than are teens whose toddler years were spent largely at home.

…When answering questions that measured their impulsiveness, teens rated themselves about 16% more rash in their behavior for every additional 10 hours they spent per week in day care as a preschooler.

In terms of risk-taking, the link to time spent in day care was more marginal: Ten more hours a week in day care prompted the average teen to answer one out of 30 questions with an admission of more risky behavior.

…“You end up with contagion effects,” said Belsky, a professor of psychology at Birkbeck University of London.

In classrooms and peer groups populated by kids who may be just a little more impulsive or risk-taking, “these small effects end up being spread and bounce off each other,” said Belsky in an interview. “The dynamic becomes, ‘I dare you to take a risk, you dare me to take a risk.’”

Preschool daycare quality matters a lot:

For teens who had [high quality day] care, the study found strong advantages in academic performance, and some behavioral benefits too.

But kids reaping those benefits were clearly the exception. Among the 1,364 children enrolled in the study, 60% were considered to have gotten child care of low to moderately low quality, and only 16% got care that was rated highly.

And it’s not necessarily true that greater impulsiveness and risk-taking are bad things (esp. for an initially shy kid like my son):

“Risk-taking, thinking creatively, taking on a challenge, trying something new — all these aspects of impulsiveness and risk-taking can be a positive thing,” [Ellen Galinsky, author of “Mind in the Making”] said.

Posted by James on Friday, May 14, 2010