Summary: New research following children for more than a decade links high screen exposure before age two to accelerated brain maturation, slower decision-making, and increased anxiety by adolescence. Infants with more screen time showed premature specialization in brain networks involved in visual processing and cognitive control, which later reduced flexibility during thinking tasks.
These developmental changes were associated with slower reaction times at age eight and higher anxiety at age thirteen. The findings highlight infancy as a uniquely sensitive period for brain development โ one where screens may shape neural pathways in ways that only emerge years later.
Key Facts:
- Sensitive Period: Screen exposure before age two, but not at ages three or four, predicted long-term brain changes.
- Altered Brain Networks: Infants with high screen time showed accelerated but inefficient maturation in networks for vision and cognitive control.
- Later Effects: These brain differences predicted slower decision-making at age eight and higher anxiety symptoms by age thirteen.
Source: ASTAR
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 new research 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, using data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort.
Published in eBioMedicine, the study tracked the same children over more than a decade, with brain imaging at multiple time points, to map a possible biological pathway from infant screen exposure to adolescent mental health. 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.
Importantly, the study focuses on infancy, a period when brain development is most rapid and especially sensitive to environmental influences. Furthermore, 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.
Infant screen exposure: why the first two years matter
The researchers followed 168 children from the GUSTO cohort and conducted brain scans at three time points (ages 4.5, 6, and 7.5). This allowed them to track how brain networks developed over time rather than relying on a single snapshot.
Children with higher infant screen time showed an accelerated maturation of brain networks responsible for visual processing and cognitive control. The researchers suggest this may result from the intense sensory stimulation that screens provide. Notably, screen time measured at ages three and four did not show the same effects, underscoring why infancy is a particularly sensitive period.
“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.”
This premature specialisation came at a cost: 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, in turn, reported higher anxiety symptoms at age 13.
These findings suggest that screen exposure in infancy may have effects that extend well beyond early childhood, shaping brain development and behaviour years later.
How parent-child reading counteracts screen time impact
In a related study published in Psychological Medicine in 2024, the same team found that infant screen time is also associated with alterations in brain networks that govern emotional regulation โ but that parent-child reading could counteract some of these brain changes.
Among children whose parents read to them frequently at age three, the link between infant screen time and altered brain development was significantly weakened. 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.
“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.
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.
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.
Funding:
ECL received grant from MOH-001784-00: Promoting early relational health with PlayReadVIP to prevent socioeconomic disparities in child development (unrelated to the manuscript) and works in an unpaid role KidSTART Ltd (Charity status), International Community School. All other authors declare that they have no conflicts of interest.
Key Questions Answered:
A: It accelerates the specialization of visual and cognitive-control networks before optimal connections have formed, reducing later cognitive flexibility.
A: No. Only screen exposure in the first two years predicted altered brain network development and later mental health outcomes.
A: Yes. Frequent shared reading at age three weakened the brain-network alterations linked to early screen exposure, suggesting a protective effect.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this neurodevelopment and mental health research news
Author: Owen Sia
Source: ASTAR
Contact: Owen Sia – ASTAR
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Neurobehavioural Links from Infant Screen Time to Anxiety” by Huang Pei et al. EBioMedicine
Abstract
Neurobehavioural Links from Infant Screen Time to Anxiety
Background
Infant screen time is linked to many negative outcomes, including anxiety, but the underlying neural correlates and pathways remains understudied. We aimed to assess the directional association between infant screen time, development of brain network topology, decision-making behaviour and anxiety symptoms in adolescence.
Methods
Using data from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort study, we examined the effects of total daily screen time for infants on developmental outcomes using structural equation modelling. Specifically, we looked at the developmental slopes of network integration for the seven major brain cortical networks between ages 4.5, 6.0, and 7.5, decision-making behaviour assessed using the Cambridge Gambling Task (CGT) and anxiety symptoms assessed using the Multidimensional Anxiety Scale for Children, 2nd Edition (MASC).
This study included 168 children from the GUSTO cohort with data on infant screen time (ages 1โ2), diffusion MRI (ages 4.5โ7.5), data on decision-making performance (CGT at age 8.5), and anxiety symptoms (MASC at age 13). Brain network integration was derived from diffusion MRI and each participant’s developmental slopes were modelled using latent growth models. Structural equation modelling assessed pathways linking early screen time to adolescent anxiety, mediated by brain network development and decision-making.
Findings
Higher infant screen time was associated with a steeper decline in visual-cognitive control network integration from ages 4.5โ7.5 years (ฮฒ = โ1.03 (โ1.61, โ0.46)), which mediated increased CGT deliberation time at age 8.5. Deliberation time, in turn, was associated with greater anxiety symptoms at age 13. A full serial mediation pathway was significant, linking infant screen time to later anxiety via accelerated brain network maturation and decision-making behaviour (ฮฒ = 0.033 (0.002, 0.160)).
Interpretation
Higher infant screen time is linked to accelerated topological maturation of the visual and cognitive control networks, leading to prolonged decision latency and increased adolescent anxiety. Sensory processing impairment may underlie this novel neurodevelopmental pathway, highlighting a potential target for early intervention.
Funding
This research was supported by the Singapore National Research Foundation, Singapore Ministry of Healthโs National Medical Research Council (NMRC), Singapore, Institute for Human Development and Potential, Agency for Science, Technology and Research, Singapore, the Hope for Depression Research Foundation, USA, the Toxic Stress Network of the JPB Foundation, USA, and the Jacobs Foundation, Switzerland.
