Lise Eliot set out to write a book that would chart how the brains of boys and girls develop differently. But when the Chicago-based neurobiologist reviewed the scientific literature, she found surprisingly little evidence of sex differences in the developing brain.
In her new book, Pink Brain Blue Brain , Dr. Eliot argues that brains are shaped by how kids spend their time – playing with dolls versus balls – and that small, innate differences become amplified over time by parents, teachers and immersion in boy or girl culture. The following interview has been edited and condensed.
So girls aren't from Venus and boys aren't from Mars?
So much that has been talked about in terms of brain differences between boys and girls is based on studies of adults. There just isn't the data in children, or the data we have so far doesn't reveal anything dramatically different between boys' and girls' brains. I want to be clear I am talking about their brains. There are obviously pretty striking differences in behaviour.
Were the differences you saw in your own children, a girl, Julia, and two boys, Sam and Toby, one of the reasons you started researching this book?
Certainly, boys and girls are different, and my children mirrored the play differences that have been well described. My boys are and were more physically active – that is one of the more reliable differences between boys and girls.
As a parent and neurobiologist, you see this and you say, “Wow, what is different about their brains, how is that all shaped?”
It's not all about testosterone?
I'm not denying that hormonal and perhaps genetic effects shape the brain and behaviour, but what I am trying to do is bring the other side of the equation in because it has been totally overlooked for the last 25 years.
The public gets confused about this idea that brain equals nature. There are two components of our biology: nature and nurture. And 50 years of neuroscience that show how experience and environment critically shapes brain structure and function.
We have become so enamoured of genetic determinism we have lost sight that, yes, parents actually also shape children's gender behaviour – and peers and the media and culture at large.
I think people would be comfortable with the idea that boys and girls grow up in two different cultures. All you have to have to do is walk into Toys ‘R' Us and see there are two different environments that tell kids where they belong.
Was there an “aha” moment when you realized that there isn't evidence that boys and girls brains are that different?
I was very frustrated that I wasn't finding more neuroscience early on to show what is different between boys' and girls' brains. That forced me to look at the adult findings, and there I was really shocked to learn that some of the adult differences we were all taking for granted were not well proven and in fact some of these findings are turning around.
