In today’s world, screens are everywhere. Children use them for learning, talking to friends, and having fun.
Since the COVID-19 pandemic, young people have been spending even more time on digital devices because of online classes and being stuck at home. While screens can be helpful, using them too much has been linked to problems like poor sleep, less exercise, and behavior issues.
One behavior issue that researchers are especially worried about is ADHD, or attention-deficit/hyperactivity disorder. Kids with ADHD often have trouble focusing, staying still, or stopping themselves from doing things too quickly.
Many studies have noticed that children who use screens more often also show stronger signs of ADHD. But most of those studies only looked at one moment in time, so we didn’t know if screen time actually caused changes in the brain or ADHD symptoms over the long term.
To better understand this, a group of scientists in Japan, led by Dr. Qiulu Shou and his team from the University of Fukui, did a large study using data from the U.S.
They looked at more than 11,000 children, starting when the kids were 9 or 10 years old. The scientists followed them for two years to see how screen time might affect brain growth and ADHD symptoms.
The results were clear: kids who spent more time using screens had more severe ADHD symptoms two years later. This was true even after accounting for how many symptoms they had at the start of the study. The researchers used brain scans and reports from parents to understand what was happening.
They found that heavy screen use was linked to smaller brain sizes in some important areas. For example, children with more screen time had a smaller cortex—the outer layer of the brain that helps with thinking, planning, and decision-making.
They also had a smaller part of the brain called the right putamen, which is important for learning and rewards.
Over the two years, the brains of kids who used screens more didn’t grow as much in some key areas. This included parts of the brain that help with understanding language and controlling actions. This suggests that using screens a lot could slow down how the brain develops.
The scientists also found that smaller brain size helped explain why screen time and ADHD symptoms were connected. In other words, too much screen time may cause the brain to develop more slowly, which then leads to more ADHD-like behavior.
These findings are important for parents, teachers, and everyone who cares about children’s health. The study shows that too much screen time might not just affect behavior—it could also change how the brain grows.
That’s why the researchers suggest that it’s a good idea to limit how much time children spend in front of screens each day.
By understanding how screen time affects the brain, we can create better digital tools and learning environments that help children grow in healthy ways. This research is a big step in helping us protect kids’ mental and emotional well-being in a digital world.
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The study is published in Translational Psychiatry.
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