This study investigated associations between screen-use (time and type) and cognition in children and tested the hypothesis that across all screen types, time spent on screens is negatively associated with cognition.
This study presents cross-sectional data from 11,875 US children aged 9–10 years. Exposures were self-reported daily recreational screen-use. The primary outcome was global cognition measured by the Youth NIH Toolbox®. Covariates included child education, pubertal development, parental education, household income, race/ethnicity, physical activity, and sleep duration.
The mean (SD) daily recreational screen time was 3.8 (3.1) hours and 99.7% of children reported using some form of screen daily. More screen time was accumulated on weekends compared to weekdays [4.6 (3.6) vs. 3.5 (3.1) hours, d = 0.34, p < 0.001], and boys reported more screen time than girls [4.1 (3.1) vs. 3.4 (3.0) hours, d = 0.22, p < 0.001]. Children in the high (7.2 h/day; β = −1.76 [-2.12, −1.40]) and middle (2.9 h/day; β = −0.82 [-1.15, −0.48]) daily screen time tertiles had lower measures of cognition compared to children in the low tertile (1.2 h/day). Children in the high tertile for TV watching (2.5 h/day; β = −0.99 [-1.55, −0.64]), video watching (2.3 h/day; β = −1.05 [-1.43, −0.67]), and social media (1.4 h/day; β = −0.79 [-1.14, −0.44]) had lower measures of cognition compared to children in the low tertile for each variable (0.3 h/day, 0.1 h/day, and 0.0 h/day, respectively). Higher video game time was positively associated with cognition compared to the low tertile (β = 0.12 [-0.25, 0.48], p = 0.53).
Higher daily screen time is associated with lower cognition in children. These findings suggest moderating screen-use for promoting cognitive development in children.
Senior Scientist and Director, Healthy Active Living and Obesity, CHEO Research Institute