Early exposure to screens during infancy may leave lasting imprints on brain development, influencing how teenagers think, make decisions, and cope with anxiety, according to a new long-term study conducted in Singapore.
The research was led by Tan Ai Peng, Assistant Professor at the A*STAR Institute for Human Development and Potential, in collaboration with the NUS Yong Loo Lin School of Medicine. The findings were published in the peer-reviewed journal eBioMedicine.
The study drew on data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort, a large, long-running research project that has followed children from birth into adolescence. By tracking the same individuals for more than a decade and combining behavioural assessments with repeated brain scans, researchers were able to identify potential biological links between early-life screen exposure and later mental health outcomes.
Why Infancy Matters
The research focused specifically on the first two years of life, a period when the brain develops at its fastest pace and is especially sensitive to environmental influences. During infancy, screen exposure is almost entirely shaped by parents and caregivers, making this stage critical for early guidance.
The team followed 168 children from the GUSTO cohort and conducted brain scans at ages 4.5, 6, and 7.5, allowing them to observe how brain networks evolved over time rather than relying on a single snapshot. This longitudinal approach makes the study the first of its kind to link screen exposure in infancy with brain development patterns measured over more than ten years.
Children who experienced higher levels of screen exposure before the age of two showed accelerated maturation of brain networks associated with visual processing and cognitive control. Notably, screen time measured at ages three and four did not produce the same effects, reinforcing the idea that the earliest years are uniquely sensitive.
Faster Brain Development — But at a Cost
“Accelerated maturation happens when certain brain networks develop too fast, often in response to adversity or strong external stimulation,” said Huang Pei, the study’s first author.
“During typical development, brain networks gradually become more specialised,” Dr Huang explained. “However, in children with high screen exposure, networks related to vision and cognition became specialised earlier, before efficient connections supporting complex thinking had fully developed. This premature specialisation may reduce flexibility and resilience, making it harder for children to adapt later in life.”
The effects extended well beyond early childhood. At age 8.5, children with these altered brain patterns took longer to make decisions during a cognitive task. By age 13, those same children reported higher levels of anxiety, suggesting a long-term link between early brain changes, decision-making speed, and emotional well-being.
Reading as a Protective Factor
In a related study published in Psychological Medicine in 2024, the same research team identified a potential protective factor: parent-child reading.
Children whose parents read to them frequently at age three showed a much weaker association between early screen exposure and altered brain networks. Researchers believe shared reading offers experiences that screens cannot replicate, including two-way interaction, language development, emotional connection, and responsive communication.
“This research gives us a biological explanation for why limiting screen time in the first two years is so important,” said Assistant Professor Tan. “At the same time, it shows that parental engagement—especially activities like reading together—can help offset some of the negative effects.”
Implications for Parents and Policy
The study involved researchers from the National University Hospital, KK Women’s and Children’s Hospital, and McGill University. Together, their findings add new biological evidence to support existing recommendations that limit screen exposure in infancy.
Experts say the results could help inform early childhood policies, healthcare guidance, and everyday parenting practices. While screens are now a common part of family life, the research underscores that what happens in the first two years matters deeply, and that simple, low-cost interventions—like reading and responsive interaction—can play a powerful role in supporting healthy brain development.
The findings reinforce a growing scientific consensus: in early childhood, human interaction matters more than screens, and small choices made early can shape emotional and cognitive outcomes years later.
