A recent study has revealed that longer screen time before the age of two could lead to slower decision-making and increased anxiety.
“Children exposed to high levels of screen time before age two showed changes in brain development that were linked to slower decision-making and increased anxiety by their teenage years,” according to a Dec. 30 press release.
The new research was published in eBioMedicine and was conducted by Asst Prof Tan Ai Peng and her team from A*STAR Institute for Human Development and Potential (A*STAR IHDP) and National University of Singapore (NUS) Yong Loo Lin School of Medicine.
“The study focuses on infancy where brain development is most rapid and especially sensitive to environmental influences,” it stated.
“This is the first paper on screen time to incorporate measures spanning over ten years, highlighting the long-lasting consequences of screen time in infancy,” it added.
The study tracks the same children over more than a decade, with brain imaging at multiple stages of their lives to explore the effects on mental health in adolescence from exposure to screen during infancy.
The study uses data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort.
The GUSTO cohort involves 168 children where researchers conducted brain scans at the ages of 4.5, 6, and 7.5.
The researchers found that children with higher infant screen time showed an accelerated maturation of brain networks responsible for visual processing and cognitive controls, suggesting this may result from the intense sensory stimulation that screens provide.
Screen time measured at ages three and four did not show the same effects, underscoring why infancy is a particularly sensitive period.
Children with these altered brain networks took longer to make decisions during a cognitive task at age 8.5, suggesting reduced cognitive efficiency or flexibility.
Those with slower decision-making reported higher anxiety symptoms at age 13.
The findings suggest that screen exposure in infancy may have effects that extend well beyond early childhood, shaping brain development and behaviour years later.
“Accelerated maturation happens when certain brain networks develop too fast, often in response to adversity or other stimuli,” explains Dr Huang Pei, the study’s first author.
“During normal development, brain networks gradually become more specialised over time.”
“However, in children with high screen exposure, the networks controlling vision and cognition specialised faster, before they had developed the efficient connections needed for complex thinking. This can limit flexibility and resilience, leaving the child less able to adapt later in life,” Dr Huang added.
Parent-Child Reading
The press release stated that “the amount and type of screen exposure in infancy are largely determined by parental and caregiver awareness and parenting practices, highlighting a critical window for early guidance and intervention.”
A related study published in Psychological Medicine in 2024 found that parent-child reading could counteract some of the brain changes associated with higher screen time in infancy, according to the release.
The study was conducted in collaboration with researchers from the National University Hospital of Singapore, KK Women’s and Children’s Hospital, and McGill University.
It reveals the link between infant screen time and altered brain development was significantly weakened among children whose parents read to them frequently at age three.
The researchers suggest that shared reading may provide the kind of enriched, interactive experience that passive screen consumption lacks, including back-and-forth engagement, language exposure, and emotional connection.
The findings provide an evidence base to guide early childhood policies and parenting practices, contributing to Singapore’s efforts to maximise human potential from the earliest stages of life.
“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, Clinician-Scientist at NUS, and the study’s senior author.
