Canadian children are spending a lot of time on their screens, and there’s new evidence that all that scrolling and liking is having a negative impact on their mental health.

A study published this summer by staff at Western University suggests a moderate link between total screen time and what researchers call "negative internalizing behaviours" — symptoms of anxiety and stress in children.

The link between screen time and anxiety is even stronger when parents are feeling high stress levels, researchers said.

“We saw that some children were hit very hard during the pandemic,” Emma Duerden, one of the study’s authors, told CTV National News.

She said the latest research suggests some children are even more at risk — those who may have undiagnosed mental health conditions.

The study analyzed the behaviours of more than 100 Canadian children from six to 12 years old, and found that — on average — children are spending about 4 hours a day with televisions, smartphones or tablets.

That is significantly higher than pre-pandemic levels, and Duerden said it hasn't reduced much since its peak during the first round of COVID-19 lockdowns.

“In really habitual screen time users, children who are checking their phone constantly, this is activating brain regions involved in reward, but also punishment,” she said. “They’re getting constant notifications when the brain is really developing, and they’re — especially for teenagers — they’re so sensitive to rewards.”

Dr. Michelle Ponti, a pediatrician, told CTV National News this research corroborates the things she deals with in her clinical practice.

“We're seeing anxious kids, depressed kids. We're seeing kids with body image issues and eating disorders walk through our office doors every single day,” she said. “The other thing we’re seeing is distressed parents.”

Ponti, a member of the Canadian Pediatric Society’s Digital Health Task Force, called the new study “high quality Canadian data,” and said it’s helpful to guide pediatricians who are speaking to parents about social media and technology use.

The task force called on the federal government Friday to become more involved in regulating excessive technology use in youth.

“It's much bigger than the individual parent and child and family,” she said. “We’re really calling on policymakers to have tighter regulations and restrictions on what apps are appropriate for kids.”

The group has asked the federal government to strengthen standards on age-verification policies, restrict what types of data can be collected in Canada and do more to restrict what ads can be shown to children.

As for parents, Ponti recommends trying to find a strategy that can work, and sticking to it — like keeping phones out of bedrooms.

“I often recommend just pick one thing, one strategy that you can implement, because it’s hard to rein it in.”