Children exposed to significant screen time before the age of two may experience changes in brain development that are linked to slower decision-making and increased anxiety during adolescence, according to new research led by Assistant Professor Tan Ai Peng from the A*STAR Institute for Human Development and Potential (A*STAR IHDP) and the National University of Singapore (NUS) Yong Loo Lin School of Medicine. The study used data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort.
The research, published in eBioMedicine, followed 168 children over more than ten years. Brain scans were conducted at ages 4.5, 6, and 7.5 to observe how their brain networks developed over time. This approach allowed researchers to track developmental changes rather than relying on single-point observations.
Findings indicated that higher levels of infant screen time were associated with accelerated maturation of brain networks involved in visual processing and cognitive control. The team suggests this could be due to intense sensory stimulation from screens during infancy—a period when the brain is particularly sensitive to environmental influences. However, similar effects were not observed with screen exposure measured at ages three or four.
This early specialization appeared to have drawbacks: children who had altered brain networks due to high infant screen time took longer to make decisions during a cognitive task at age 8.5, indicating reduced cognitive efficiency or flexibility. By age 13, those with slower decision-making reported higher anxiety symptoms. The results suggest that early screen exposure can have lasting impacts on brain development and behavior into adolescence.
In another related study published in Psychological Medicine in 2024 by the same team, it was found that parent-child reading at age three could counteract some negative effects of infant screen time on emotional regulation networks in the brain. Among children whose parents read frequently with them, the link between early screen use and altered brain development was significantly weakened.
"This research gives us a biological explanation for why limiting screen time in the first two years is crucial. But it also highlights the importance of parental engagement, showing that parent-child activities, like reading together, can make a real difference," said Asst Prof Tan Ai Peng, Principal Investigator at A*STAR IHDP and Clinician-Scientist at NUS.
The study was conducted with collaborators from National University Hospital of Singapore, KK Women's and Children's Hospital, and McGill University. According to researchers, these findings provide evidence for shaping early childhood policies and parenting practices aimed at supporting child development from an early stage.
