A long-running Finnish study tracking children from early elementary school into adolescence has found that those who spent more time on screens over the years tended to show better cognitive processing as teenagers — a result that cuts against the common assumption that screen time is straightforwardly harmful to young minds.
The findings come from the PANIC study (Physical Activity and Nutrition in Children) at the University of Jyväskylä in Finland, published in the journal Pediatric Exercise Science. Researchers followed 260 children — 124 girls and 136 boys — for eight years, measuring physical activity, sedentary behavior and screen use repeatedly, then testing cognitive processing when participants reached an average age of 15.8.
Activity type mattered as much as screen use
Accumulated screen time across childhood and adolescence was associated with better, not worse, cognitive processing scores at follow-up. The relationship was not uniform, however: girls showed cognitive benefits tied to light-intensity physical activity, particularly for working memory, while boys showed improvements linked to guided, structured physical activity rather than unstructured movement. The study builds on data first described in a related preprint analysis of the same PANIC cohort.
"Screen time can support children's and adolescents' cognitive processing," said Petri Jalanko, a doctoral researcher at the University of Jyväskylä and the study's first author. "Presumably, the essential point here is what kind of things they do in their screen time" — suggesting that activities requiring active thinking, problem-solving or learning may drive the association, as opposed to passive viewing.
The connections of physical activity and sedentary behavior to cognitive processing are complex and depend on the sex, the type and assessment method of physical activity and sedentary time.
Petri Jalanko, University of Jyväskylä
The result arrives amid an ongoing global debate over youth screen use, with many health authorities and school systems moving toward stricter limits on phones and devices for children and teenagers. Jalanko and colleagues were careful to frame their result as an association rather than proof that screens improve thinking, noting that the study cannot rule out that other factors — such as the specific content children engaged with, or family and school environments — explain both higher screen use and stronger cognitive scores.
Independent science outlets covering the release, including a U.S. News & World Report summary, echoed the researchers' caution that the findings should not be read as a green light for unlimited screen use. The Jyväskylä team said its next step is designing intervention studies that could test cause and effect directly, by manipulating the type and duration of screen activities and physical activity in controlled settings rather than only observing them.
