If you're thinking of plopping your infant in front of a screen to get some peace and quiet, you might want to reconsider - higher screen exposure in infancy was linked to longer decision times later on and higher anxiety symptoms in the teenage years.

A group of Singaporean researchers who studied a cohort of 168 children for more than a decade found that those exposed to screens in infancy (before two years of age) showed accelerated maturation of brain networks involved in visual processing and cognitive control. That faster specialization, the researchers suggest, was associated with slower decision-making in childhood, and in turn, higher anxiety symptoms in adolescence.

"During normal development, brain networks gradually become more specialised over time," according to the study's lead author Dr. Huang Pei. "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."

The result, Huang said, is limited brain flexibility and mental resilience, leaving children less adaptable later in life, as evidenced by higher anxiety scores in cohort kids who had more screen time before age 2. 

The researchers, who were mostly associated with Singapore’s Agency for Science, Technology and Research (A*STAR) Institute for Human Development and Potential, conducted the study to take a closer look at the association between infancy screen exposure, brain development, and behavioral outcomes, which they said has been lacking in prior similar research. 

Children who were included in the cohort were selected from the larger Growing Up in Singapore Towards healthy Outcomes (GUSTO) study, which has been following more than 1,400 mother-child pairs since 2009. 

Screen exposure in infancy was measured through self-reporting by the children's parents, while MRI scans were taken of children's brains at ages 4.5, 6, and 7.5 to examine physiological changes across the cohort. Children were also given cognitive tests at age 8.5 to measure their decision-making behavior, and were given an anxiety questionnaire at age 13. 

The researchers found that infant screen time was significantly associated with accelerated maturation of the visual–cognitive control network in the brain. Children showing this faster network maturation also took longer to make decisions in a cognitive task in childhood, and in turn, reported higher anxiety symptoms in adolescence.

No one likes an iPad kid

The authors call their work critical for the future of public health. 

According to the paper, infants in the cohort were averaging "more than one to two hours of daily screen time." The World Health Organization, the researchers point out, says sedentary screen time is not recommended for 1-year-olds and should be limited to no more than one hour per day for 2-year-olds, with “less is better” still the advice.

"The levels of infant screen use observed in our study cohort are concerning, both in their magnitude and in their clear divergence from WHO recommendations," the team noted in their paper.

To make matters worse, they estimate that their screen time data, collected between 2010 and 2014, is probably lower than today's average. 

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"Our data … precede recent evidence of further increases globally, particularly during the COVID-19 pandemic," the team said. "The already elevated levels of screen exposure we observed a decade ago are likely even higher today, making the developmental implications of our findings especially urgent."

The same research team also published a paper last year using GUSTO data examining infant screen time in relation to socio-emotional development. Unsurprisingly for any parent who has ever had to separate a child from an iPad, management of emotions was stunted in screen-saturated youngsters. 

So, what is a new parent to do when confronted with a growing amount of screen time in adults, children, and infants, and multiple research results that suggest it's bad for the brain? Put down the smartphone and stow the iPad in favor of a good, old-fashioned book.

Children whose parents frequently read to them at age three showed a weakened link between screen time and altered brain development, meaning active engagement and enrichment brought by reading to children and asking them questions about the books shared with them helps foster better emotional management, language skills, and, in the case of the latest study, is likely to help their brains develop at a consistent, healthy rate across various cognitive areas.

"This research gives us a biological explanation for why limiting screen time in the first two years is crucial," A*STAR researcher and senior author of the study, Tan Ai Peng, said. "But it also highlights the importance of parental engagement, showing that parent-child activities, like reading together, can make a real difference." 

In other words, if you want a healthy child, turn off the screens and pull out the books. Tech is not a helpful babysitter. 

Oh, and it's probably a good idea to keep them away from AI, too. ®