More screen time, sharper thinking?

Clinical takeaway: Screen time may not be uniformly harmful for cognitive development. The type and context of screen use may matter, while reinforcing the importance of balancing screen time with physical activity.

Screen time is often treated as a behavior to minimize in children and adolescents. A Finnish study complicates that message: greater cumulative screen time from childhood through adolescence was associated with better working memory and overall cognitive performance at about age 16.

Researchers followed 260 children for eight years, assessing self-reported screen time, physical activity, and other sedentary behaviors at multiple points. Cognitive performance was measured in adolescence, with analyses accounting for baseline nonverbal reasoning, age, sex, and parental education.

Greater cumulative screen time was associated with faster reaction times on two working-memory tasks and better overall cognition. Among girls, more screen time was also associated with better overall cognition and faster working-memory performance.

Importantly, the study did not determine what participants were doing on their screens. Screen time included television and videos, computers, video games, mobile phones, and mobile games. The authors suggest that cognitively engaging activities, such as gaming or other screen-based tasks requiring problem-solving, could partly explain the unexpected association.

The results should not be interpreted as evidence that more screen time improves cognition. The study was observational, cognition was comprehensively assessed only at follow-up, and screen use was self-reported. Device-measured sedentary time, meanwhile, was not associated with cognition, suggesting that how sedentary time is spent may matter more than simply how much occurs.

That distinction may be useful when families ask about screens: duration alone may provide an incomplete picture. Content, cognitive engagement, physical activity, and overall balance may be more informative targets for counseling than treating every hour of screen use as equivalent.

“We should not regard screen time solely as harmful but seek balance between physical activity and screen time that promotes active thinking,” said Petri Jalanko, a doctoral researcher at the University of Jyväskylä.

Source: Jalanko P, et al. (2026 May 29) Pediatr Exerc Sci. Associations of Physical Activity and Sedentary Time From Childhood to Adolescence With Cognition in Adolescence: The PANIC Study