Teen Brains: Seeing the Big Picture
Ability to See Other Points of View Develops in Teen Years
By Kathleen Doheny
WebMD Health News
Reviewed by Laura J. Martin, MD


Nov. 15, 2010 (San Diego) -- For parents who grow frustrated with their children's seeming inability to understand others who have different points of view, here's hope from the scientists:

Give it a few more birthdays. Teen brains get better in this regard.

As children mature, the regions in a specific brain network known as the default-mode network or DMN begin to work together, and parents are likely to notice a difference in the children's ability to look outside themselves, according to new research presented here at Neuroscience 2010, the annual meeting of the Society for Neuroscience.

''Between 13 and 19, the regions of the DMN start to work in concert," researcher Stuart Washington, PhD, a postdoctoral research fellow at Georgetown University and Children's National Medical Center in Washington, D.C. tells WebMD. He presented his findings Sunday.

"It takes until the teen years for the DMN to develop," he says. That's the case in typically developing children, he says, but not in those with autism, he also found in the study.

When he compared the typically developing children he studied with those with autism, ages 7 to 17, he didn't find the DMN worked more in concert as the autistic children grew older.
What Is DMN?

Scientists have been focusing on the DMN for about the last decade, Washington says. The network, not yet fully understood, consists of five scattered regions that "ramp up" when we daydream or the mind is at rest.

It's been linked with introspection, the ability to understand one's own point of view or beliefs and that others may have different points of view or beliefs. It's also been linked with the ability to reflect on one's actions in the past and the consequences of them.
Study Details

Previous research has focused on the DMN activity in adults or compared activity in adults with that in children, but Washington wanted to track it over four age groups.

So he used functional MRI images to evaluate the DMN activity in 41 participants, including:

    * 10 children ages 6 to 9
    * 12 children ages 10 to 12
    * 9  teens ages 13 to 19
    * 10 adults ages 22 to 27

Each time, participants were given a task to do during the imaging, but the researchers looked at brain activity after the task was done, during the resting phase.

The connectivity increased with age, with noticeable differences emerging between children and late adolescents as well as children and adults. Then Washington looked at scans from autistic children ages 7 to 17 and found their DMN activity was most like the typically developing younger children.
Brain Activity With Age: Perspective

The new research adds to existing findings about better connectivity developing with age, says Damien Fair, PhD, a postdoctoral fellow at the Oregon Health & Science University, who says the finding about autistic children adds new information to the body of knowledge.

In previous research, Fair compared DMN activity in two age ranges of children and adults and came up with findings similar to those of Washington.

The take-home message for parents, says Motoaki Sugiura, MD, PH/D, a researcher at Tohoku University in Sendai, Japan, who also reviewed the findings for WebMD, is that "Integration of the brain takes time."