Researchers report cortical thinning in attention and memory centers among kids with heavier screen-time habits

One of the largest child-brain studies to date suggests long screen hours align with changes in regions tied to attention, memory, and impulse control.

A major US brain-development study is offering a closer look at what long stretches of screen exposure might mean for children. The research, led by teams from the University of Fukui and based on MRI data from the Adolescent Brain Cognitive Development (ABCD) study, tracked kids over two years and saw measurable differences in several brain regions tied to attention and planning.

The new study reports cortical thinning in attention and memory centers among kids with heavier screen-time habits.(Unsplash)

Changes observed in heavy screen users

Researchers followed nearly 10,116 children, beginning at ages 9–10. When they checked the same group two years later, kids reporting higher daily screen use showed thinner cortex in areas involved in working memory, impulse control, and decision-making.

Those regions included the right temporal pole, the left superior frontal gyrus, and the left rostral middle frontal gyrus.

The MRI findings lined up with earlier patterns seen in children with ADHD. At baseline, heavier screen users also had smaller volume in the right putamen, a structure linked to reward responses.

The study, published in Translational Psychiatry, cautions that these are associations, not proof that screens directly cause the changes.

ADHD-like symptoms and the two-year pattern

Parents filled out the Child Behaviour Checklist during both data points. Children with more screen time showed a small but consistent increase in ADHD-like symptoms over the two-year period. Researchers noted that reduced total cortical volume explained part of that shift.

The effect size was modest. But the trend held after accounting for age, sex, race, income, physical activity, and sleep duration. One limitation: children already struggling with attention may naturally turn to screens more often, which complicates cause-and-effect claims.

How researchers measured it

More than 10,000 MRI scans were processed using standardised software measuring cortical thickness to the millimetre. At follow-up, usable data remained for 7,880 children. Screen-time estimates included gaming, television, and smartphones.

What it means for parents

The study does not settle the larger debate about digital exposure. It does not identify harmful content types or specific usage patterns. But it does show consistent structural differences in regions supporting attention and self-control during a key developmental window. The authors suggest future work focus on functional connectivity to understand how these areas communicate, not just how large they are.

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.