Summary: A new longitudinal study shows that when children are exposed to screens can be as important for long-term cognitive development as how much time they spend in front of screens. Neuroscientists and pediatric researchers followed 502 children for nearly a decade, recording parent-reported screen use at six time points from age 1 through age 8 and later testing academic achievement and working memory in middle childhood.
Overall, the research found a consistent association between higher screen viewing during infancy (around 12 months) and again near the start of formal schooling (around 6 years) with poorer academic performance at age 9 and reduced working memory at age 10.5. In contrast, screen use during mid-toddler years (ages 2–3) showed little or no long-term link to academic outcomes in this cohort, highlighting two distinct windows of heightened sensitivity.
Key Facts
- U-shaped pattern of sensitivity: Long-term cognitive differences were strongest when high screen exposure occurred in infancy and around school entry; mid-toddler years showed weaker associations.
- Infancy as the highest-risk period: Screen exposure at 12 months produced the largest negative effect sizes on subsequent learning and working memory measures across the study.
- Displacement of interactive learning: Excessive screen time in infancy appears to displace essential face-to-face, reciprocal interactions that support language, attention, and early memory circuits.
- Working memory impacts: Elevated screen exposure in infancy and at school-entry age corresponded with measurable declines in working memory at 10.5 years—skills central to reading comprehension, math, and complex problem solving.
- Public health implications: While the effect of an extra hour may be modest for an individual child, small average shifts across large populations can move many children into lower academic performance brackets.
Source: Zhejiang University
Why this study matters
As screens have become nearly universal in young children’s lives, parents, clinicians, and policymakers need clearer evidence about long-term effects. Previous research was often cross-sectional, focused on older children, or lacked repeated measures during early development. This study addresses those gaps by tracking the same children across key developmental stages, allowing researchers to identify specific ages when screen exposure is most strongly linked to later cognitive outcomes.
Researchers used data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort. Parents reported their child’s typical daily screen viewing at ages 1, 1.5, 2, 3, 6 and 8 years. Trained psychologists later measured academic achievement at age 9 and working memory at 10.5 using standardized assessments.
The sample included 502 children with complete data on exposure and outcomes. Average reported screen time rose from about 2.1 hours per day at age 1 to roughly 3.0 hours per day by age 8. Analyses adjusted for family and environmental factors found persistent associations between higher screen use at specific ages and poorer later outcomes.
Notably, screen exposure at 1 year had the largest adjusted effect sizes: each additional hour per day at 12 months was linked to a measurable decrease in standardized academic scores at age 9 and lower working memory scores at 10.5. Elevated use at 1.5 and at school-entry age (6 years) also showed significant associations with academic outcomes after adjustment. Cumulative average screen time across childhood was consistently associated with reduced academic performance but showed a weaker and less consistent relationship with working memory.
The authors interpret these findings as supporting a precautionary approach: limiting screen time during early infancy and reinforcing restrictions around the transition into formal schooling could protect learning and memory development. They stress that content quality, device type, and parental co-viewing are additional factors that likely influence developmental outcomes and merit further study.
Recommendations and public health context
These results align with existing guidance from major child-health organizations that recommend minimal or no screen exposure in the first 18–24 months and limited, high-quality media for toddlers and preschoolers. For policymakers and clinicians, the findings suggest targeted public health messaging that emphasizes reduced screen exposure during infancy and attentiveness to screen habits at school entry may yield the greatest long-term benefit.
Funding information
The GUSTO study received support from the Singapore National Research Foundation and the Singapore Ministry of Health’s National Medical Research Council (NMRC/TCR/004-NUS/2008 and NMRC/TCR/012-NUHS/2014). Additional support came from the Agence Nationale de la Recherche (ANR) in France (iSCAN project, ANR-20-CE36-0001).
Key Questions Answered:
A: Around 12 months, the infant brain undergoes rapid synaptic growth and benefits most from rich, reciprocal, face-to-face interactions that build language, attention, and early memory systems. Screens are non-reciprocal and can displace these interactive experiences, reducing the hands-on and social learning that support foundational neural wiring.
A: The team was surprised by a non-linear pattern: strong associations at infancy, little link during ages 2–3, and then a re-emergence of negative associations at age 6. This suggests vulnerable windows recur and that screen habits around school entry can again influence cognitive adjustment to formal learning environments.
A: Not necessarily on an individual level. The estimated effects for a single child may be small and hard to detect day-to-day. The concern is population-level: modest average increases in screen exposure can shift the overall distribution of academic and cognitive performance, moving a substantial number of children into lower outcome ranges.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- The journal paper was reviewed in full.
- Additional context was added by our staff.
About this neurodevelopment and memory research news
Author: Editorial Office
Source: Zhejiang University
Contact: Editorial Office – Zhejiang University
Image: The image is credited to Neuroscience News
Original Research: Open access. “Screen viewing time from age 1 to 8 years and subsequent academic performance and working memory” by Shuai Yang et al., published in the World Journal of Pediatrics. DOI: 10.1007/s12519-026-01046-1
Abstract
Screen viewing time from age 1 to 8 years and subsequent academic performance and working memory
Background
Screen viewing time has been linked to children’s academic and cognitive outcomes, but longitudinal evidence that can identify sensitive age periods is limited. This study examined associations between single-age and cumulative average screen viewing time and later academic performance and working memory.
Methods
Within the GUSTO birth cohort, parents reported daily screen viewing at ages 1, 1.5, 2, 3, 6 and 8 years. Trained psychologists later assessed academic performance (Wechsler Individual Achievement Test–Third Edition) at age 9 and working memory (Letter-Number Sequencing, WISC-V) at age 10.5. Multivariable linear regression models examined associations for N = 502 children.
Results
Average screen time increased from approximately 2.1 hours/day at 1 year to 3.0 hours/day at 8 years. In unadjusted analyses, higher screen viewing across ages 1–8 correlated with poorer academic performance at age 9 and reduced working memory at 10.5. After adjusting for confounders, screen time at 1 year (β = –1.47 per additional hour/day), 1.5 years (β = –0.95), and 6 years (β = –0.88) remained associated with lower academic scores. For working memory, greater exposure at 1 year (β = –1.12) and 6 years (β = –1.01) predicted poorer outcomes. Cumulative average exposure predicted lower academic performance but showed weaker associations with working memory.
Conclusion
In this longitudinal cohort, cumulative screen viewing across childhood was associated with lower academic performance, and the largest single-age effects were observed for screen exposure during early infancy. These findings highlight early infancy and school-entry as developmental windows when screen habits may have particularly lasting implications for learning and memory.