We know that executive function develops over time. Now, we may have a better idea of why—and how. As kids grow older, their executive skills strengthen. They get better at skills like planning, organizing and focusing. A recent study of brain scans shows how this improvement is linked to the specialization of key brain networks. The study was funded by the National Institute of Mental Health and published in Current Biology. Researchers looked at “diffusion” brain scans of 882 young people, ages 8 to 22, in Philadelphia. This type of MRI scan produces colorful images of brain structures by scanning water molecules. Understood experts Ellen Braaten and Bob Cunningham reviewed the study. Here’s the takeaway. Key Findings In recent years, experts have learned that the brain is organized into networks. These networks crisscross different areas of the brain and are activated by different tasks. Many of these brain networks impact learning and attention issues, like ADHD. For instance, the frontoparietal network is active when the brain is making decisions and learning new tasks. The default motor network is active when the brain is resting. It also plays a role in “turning off” other brain areas. This study focused on eight brain networks linked to executive function. Looking at the scans, the researchers found these networks are more specialized, or well-defined, in older kids than in younger kids. With the younger kids, the networks were merged together. So all brain tissue was connected across networks. In the older kids, the various brain networks were more distinct, or specialized. There were fewer direct connections between brain tissue in different networks, but more internal connections within networks. At the same time, the brains of older kids had strong “hub connections.” These linked the specialized networks to each other, and integrated them in the brain. Specialization has a big impact on executive function, according to the study. Kids with more specialized brain networks score higher on tests of executive function. This effect is very strong for the frontoparietal and default mode networks. When these networks specialize, kids get a big executive function boost. “This is some of the best evidence we have that shows that the brain becomes more organized, connected and specialized as it matures, and that this is very important for executive function skills,” says Braaten. Key Takeaways for Parents This is an important study for helping us understand how the brain works. The researchers showed how specialization of brain networks improves brain efficiency. Plus, it’s linked to better executive function. The development of hubs between networks also seems to play a big role in the maturing brain. (It’s important to know that the findings don’t point to any specific intervention that can impact this development, however.) Although brain networks change as kids age, it doesn’t mean that executive functioning issues go away. These challenges are lifelong. However, their impact may shift over time. And it’s important to understand that kids’ brains and their abilities when they’re young aren’t set in stone. Learn how executive functioning issues are related to ADHD. Get strategies for managing these issues. And follow a day in the life of a child who struggles with executive function.