As digital media increasingly integrates into young children's lives, concerns about its impact on early development have grown. Despite expanding interest, empirical research on screen exposure during the critical first three years of life remains limited and fragmented. This systematic scoping review synthesizes findings from 158 peer-reviewed studies published between May 2007, which coincided with the emergence of the smartphone era, and July 2024. Drawing on 10 academic databases, the review evaluates how screen-based media exposure affects nine key developmental domains in children aged 0–36 months: sleep physiology, biological health indicators, cognitive processing, language acquisition, psychomotor skills, emotional regulation, social reciprocity, adaptive functioning, and overall developmental trajectories. The analysis reveals both potential risks and mixed findings across domains, and identifies significant methodological shortcomings in the existing literature. These include a lack of causal research designs, insufficient contextual detail regarding screen content and co-viewing environments, and inconsistent use of developmentally sensitive assessment tools. This review underscores the urgent need for more nuanced, longitudinal, and ecologically valid research to inform evidence-based guidelines for screen use in early childhood.
Cheng Yiyun (Fri,) studied this question.