Researchers have warned that high screen exposure between birth and two years old can lead to slower decision-making and increased anxiety later in life.

They, however, observed that it is never too late to reverse the side effects faced by children who have had too much screen time as infants, stressing that early intervention and positive lifestyle changes can help rewire developing brains.

According to scientists who spearheaded the 10-year-long study that was released last week, the side effects seen in children who were exposed to excessive screen time as infants can be reversed through measures like increased social and physical interactions.

The Researchers from the National University of Singapore (NUS), KK Women’s and Children’s Hospital and the Agency for Science, Technology and Research (ASTAR) tracked about 170 children born in 2009, beginning from birth.

The study sought to understand how conditions during pregnancy and early childhood affect a mother’s and her child’s health, growth and development. According to the report, brain scans were taken at various stages of the children’s development to study the long-term impact of early screen exposure.

They found that for children up to two years old, each additional hour of screen time was linked to them being 25 per cent slower at decision-making by age eight-and-a-half and by their teenage years, these children also showed higher anxiety symptoms. These effects were observed across all socio-economic backgrounds.

The study’s lead researcher and a clinician-scientist at NUS, Prof. Tan Ai Peng, said one example of the impact on daily life is taking a long time to decide whether to cross the road when the traffic light turns green.

She added that anxiety could appear in different ways, including excessive worry, social avoidance or physical symptoms such as increased heart rate and sleep disturbances. “All these issues with decision-making and anxiety could actually impact different dimensions of an individual’s life, from affecting an individual’s academic performance, or when they go into adulthood, it can actually affect their work performance,” said Peng, who is also a principal scientist at A STAR’s Institute for Human Development and Potential.

“If you look at interpersonal relationships, they actually also require a lot of these skills and that potentially could be impacted as well,” she added.

She warned that the consequences of screen exposure could be even more severe for children today, compared with those in the study who mainly watched television. This is because children as young as two years old have access to devices like mobile phones and tablets, she pointed out.

“That’s also the reason why research on screen time, especially in young children, is actually gaining momentum. Despite their findings, the researchers stressed that it is not too late for parents to take action. Peng observed that children’s brains are highly adaptable, and positive changes can still make a difference even after early exposure.

She noted that simple adjustments, such as replacing short periods of screen time with interactive activities, can help strengthen brain pathways, adding that other social and physical interactions that can help include reading together, playing face-to-face games, going for outdoor walks, and engaging in music and sports.

Peng highlighted that shared activities are especially important for younger children. She said, “If a child reads alone, the child is just learning a language. But when a child is reading with the parents, it is not just about the words on the pages. It is about the back-and-forth interaction, learning how to recognise facial expressions and emotions as they interact with their parents. If parents want to include devices in their children’s lives, they should not leave them alone with an iPad, for example, but sit down with their children and use it as an educational tool.”

While parents play the most critical role during infancy, healthy peer interaction becomes increasingly important as children grow older, she added.

Looking ahead, the research team plans to continue tracking the children into adulthood. They aim to assess cognitive functioning, mental health outcomes such as anxiety and depression, and conduct further brain scans to understand why some children show greater resilience than others.

The researchers are also expanding their focus beyond screen time alone to examine how it interacts with other lifestyle factors such as sleep and physical activity.

“All the adverse outcomes that we are seeing in these adolescents are actually a combination of high screen time, low physical activity and insufficient sleep. We’re hoping that we will be able to design a comprehensive intervention that could guide people to address this more holistically,” Peng added.