Nov 23, 2025
3 min read
In a study of 10,000 children, screen time was linked to thinner brain atria in the attention span and ADHD symptoms.
Children who spent more time in front of screens showed thinning of the cerebral cortex in areas of the brain involved in memory, planning and impulse control.
In short
- Differences in brain structure found: 9-10 year olds with more screen time had less thickness after two years in brain areas that control attention, memory and impulsivity.
- Links to ADHD symptoms: More screen time was a small factor in capital time and was partially explained in the study phase.
- Large-scale tracking: Researchers tracked nearly 10,000 US children through MRI scans, making it one of the most comprehensive studies of screen time and brain development.
- Link unclear: Research found a link, but couldn't prove that screens cause brain changes in people who spend too much time on the device.
What happens in a child's brain after thousands of hours in front of screens?
A survey of nearly 10,000 American children provides some answers.Researchers who followed children ages 9-10 to 11-12 found that increased screen time was associated with measurable differences in brain structure.Specifically, reduced thickness in areas that control attention, memory, and impulse control.
SNANS' MRIs showed differences that were not random.They showed the same areas of the brain that function differently in children with ADHD.Screen time is also associated with low volume of the brain's reward center and low volume of gray matter in general, and structural differences consistent with increasing symptoms of ADHD over the two years.
Research from Fukunui University in Japan Analyzed from PerhatsAn Kogram Kogram data.Their work comes when the children are working hard in front of the screen, especially since the Farm Covid-19 will accelerate the farming.
While previous research has suggested a link between screen time and brain structure, most studies have been snapshots rather than tracking actual developmental changes.This study, published in Translational Psychiatry, tracked real-world patterns of brain growth alongside behavioral changes, giving researchers a clearer picture of how screen use corresponds to changes in the developing brain over time.
Measurement of brain changes over time through screens in approximately 8,000 children
The research team analyzed data from 10,116 children at baseline and 7,880 children at a two-year follow-up.Parents reported ADHD symptoms using the Child Behavior Checklist, while calculations of screen time included all device use—video games, television, smartphones—averaged over weekdays and weekends.
Brain measurements come from high-resolution tests.The MRI works in specialized programs that specialize in programs that specialize in regions of the ears that are small in volume and thickness and in thickness and thickness that decreases in millimeters.Researchers controlled for many factors such as age, sex, gender, family income, parental education, sleep duration, and physical activity levels.
Sample Size and Longitudinal Design Set this task.Previous studies have examined small groups or looked at another point in time instead of following children as their brains actually develop.
Thinning of the cortex in centers of attention and memory
After two years, children with longer initial screening times showed measurably thinner cortex in three specific areas.The right temporal pole, involved in social cognition and language, showed reduced thickness related to screen exposure.The same happened with the left superior frontal gyrus, responsible for working memory and attention control, and the left middle frontal gyrus, associated with cognitive flexibility and decision making.
These are not arbitrary brain regions.These are exactly the areas that support the cognitive functions that are damaged in ADHD - sustained attention, impulse control, working memory and forward planning.
At the beginning of the research, longer screen time was already linked to the right putamen.This almond-sized structure sits deep in the brain and plays a key role in reward processing.It can be used as a marker of impulsive behavior when children have different probabilities to inhibit SWEOTE.
Screen-based activities provide immediate rewards and immediate incentives.Game achievements, autoplay videos, and infinite scrolls provide instant gratification.Some researchers think that immediate rewards can train young people to chase fast pay, which can help explain why users are sometimes heavy.This study did not directly test this hypothesis.
More adhd-like symptoms
Perhaps the most significant finding is total cortical volume—the total amount of gray matter in the outer layers of the brain.Children with more screen time had smaller cortical volumes, and this difference partially explained why they showed more ADHD symptoms.
This model provides a possible chain: Screen exposure is associated with the development of mild anxiety, which is then linked to attention and behavior problems.Children with ADHD have been shown in other studies to exhibit delayed cortical inference compared to their peers without the disorder.
If screen time interferes with the normal growth of the cerebral membrane, it may cause some children's brain development to deviate from normal.Studies cannot confirm this. But it raises the possibility that the cerebral cortex is where the brain performs its executive functions. It is a mental process that helps children focus, plan and control impulses.Developmental changes can affect behavior and attention.
Interestingly, the specific regions that shined over the two years did not statistically explain the relationship with ADHD screen time.The researchers noted that this could mean that functional brain networks or microstructural properties, rather than just size measurements, play a role in long-term effects.
From brain changes, research has found behavioral effects.Children who had a longer time to onset of ADHD symptoms were identified two years after their baseline measurement.
The effect remains statistically significant but moderate in size.This raises the question of whether or not individual children should be concerned, calling whether or not the data found in the population guide.Small non-living statistical associations still give clear influence in the individual world.
The relationship between music and ADHD-like behavior has been debated for many years.Some studies find only a weak link, while others report a stronger association.This study indicates a relationship and may increase the development time, although the results are small, the result is not enough, but experts are against alarm.
One complication: Children with pre-existing attention difficulties may naturally gravitate to screens rather than the screens causing the problems.Unraveling cause and effect remains difficult without experimental studies, which would be unethical to conduct by intentionally exposing children to excessive screen time.
What is the research for parents?
The study design prevents a definitive conclusion that screens cause brain differences or ADHD symptoms.While screen time preceded both brain changes and symptom increases, other unmeasured factors may be driving the associations.
Screening times were self-reported, which may lead to inaccuracies.The study also did not take into account what children were watching or how they were using their devices.Watching educational programming is significantly different from playing fast-paced video games.Screen size, lighting conditions, and whether screen time substituted for other activities were all important but not recorded.
Effect sizes across the study were sufficiently small that clinical significance remains uncertain for each individual child.A statistically detectable difference in cortical thickness does not necessarily mean that a child is struggling academically or socially.
However, the campaigns provide evidence that a large window of growth can be associated with different measured differences in brain structure.Adolescence is when the natural and environmental factors provide the best means of reproduction.During this time, the brain was young again, scaring deep connections while empowering others based on experience.
The researchers recommend that future research should include brain connectivity measures (how regions differ), rather than size.Understanding whether certain types of screens or usage patterns are more problematic than others can also help parents make informed decisions.
Structural differences were real and measurable, albite was small.They are areas of the brain involved in attention and self-control.Whether these differences prove to be meaningful in the lives of individual children is an open question that requires further research.
The cross-sectional nature of the baseline analyzes precludes causal inferences regarding the relationship between screen time, brain structure, and ADHD symptoms.Effect sizes across studies were small, raising questions about clinical significance.Screen time relied on self-report, which can be inaccurate.This study did not capture screen size, content type, or context of use.Although this study included composite variables, unobserved confounding factors may exist.The one-year follow-up period, while longer than most studies, may not capture long-term developmental effects.The study population was initially limited to children aged 9-10 years, so the results may not generalize to other age groups.
Funding and disclosure
This project was funded by the British public for the promotion of research (MPOn)Fukui (AY 2023 to Yoshifumi Mizuno and Qiulu Shou), and the Office of the New Office, University of Fukui (AY 2023 to Qiulu Shou).the case.
Shou, Q., Yamashita, M. and Mizuno, Y. (2025).The relationship between screen time and attention-deficit/hyperactivity disorder symptoms and development: the mediating role of brain structure.Translational psychiatry, 15, 447. DOI:10.1038/s41398-025-03672-1
Author affiliations: Child Mental Development Research Center, Fukui University, Fukui, Japan;Division of Higher Developmental Brain Functions, United Graduate School of Child Development, Fukui University, Fukui, Japan;Life Science Innovation Center, Fukui University, Fukui, Japan;
