A Canadian study found children who spend a lot of time watching electronic screens are more prone to anxiety, depression and aggression.Ontario children’s screen time on computers, television, video games and smartphones rose from 2.6 hours per day before the pandemic to 5.9. The average has since fallen to 3.9 hours, but the Canadian Pediatric Society recommends no more than two.“We were pretty astounded by these findings, but of course, this was a period of crisis for everyone,” lead author Emma Duerden, the Canada research chair in Neuroscience and Learning Disorders, said in a Western University press release.“If children start using screens when they’re young, then they’re more likely to use them when they’re older,” Duerden added.While other studies have shown screen time can have adverse effects on children’s mental health, Duerden says it was surprising to see such a strong association.“What we also found consistently in all of our studies was that parent stress was a key predictor of screen time,” Duerden added.“We don’t understand that association yet, it can only be inferred.”The study, published in BMC Psychology, noted, “Increased screen use in children and high parental stress were associated with increased anxious and depressive symptoms in children."“The highest scores for these internalizing behaviours [were] seen in children who had both elevated screen use and parents experiencing high stress.”The paper reinforced findings by other researchers that high screen time was associated with bad moods and behaviour.In 2022, researchers identified a “weak but significant” association between children’s screen time with aggression and emotional issues. The team analyzed 87 eligible studies from 595 articles, totalling more than 159,000 participants aged 12 or younger to reach their conclusion.“Although the effect sizes [relationship strength] found in this study were small, the consequences of screen time at a population level are likely meaningful,” the authors wrote.Externalized behavioural problems show as aggression, attention deficit, and hyperactivity in children. Internalized behavioural problems during adolescence can impact mood and emotions causing anxiety and depression.Other studies have suggested high screen time negatively affects children’s brain development.Research published in the International Journal of Sociology of the Family in 2021, links excessive screen time to “atrophy in the frontal, striatal and insula cortex regions of the brain” and a thinner orbitofrontal cortex.“Thinning of the orbitofrontal cortex has also been shown to significantly impact memory and can increase the incidence of obsessive-compulsive disorder,” the paper explains.Researchers also say they’ve seen a decline in executive functions, such as remembering instructions, paying attention, controlling impulses, delaying gratification and regulating social behaviour.A study in The Journal of Pediatrics found one hour of screen time a day can diminish executive functions in children as young as two years old.Research published in Preventive Medicine Reports found one hour per day of screen time in children and adolescents between ages two to 17 leads to less curiosity, less self-control and greater distractibility.