Screen time for kids: How to prioritize and create guidelines

New research aimed at understanding the impact of screen time and social media on adolescent brains found in early testing significant differences in brain chemistry for kids who had at least seven hours of screen time a day, compared to kids who used screens less. On "60 Minutes," contributor Anderson Cooper explored the National Institutes of Health study, which is following more than 11,000 children over a decade.

Psychologist and CBS News contributor Lisa Damour explained that the appeal of social media is "incredibly compelling."  

"We know it triggers the reward centers in the brain. And this is true for grownups too, not teenagers and kids," Damour said Monday on "CBS This Morning." "We also know that digital technology disrupts things that are important for healthy development — so sleep, one-on-one interactions that are face-to-face, learning how to focus on one's schoolwork, physical activity. So we should already start to be drawing some lines around digital technology, just to protect normal and healthy development."

While experts have offered a variety of guidelines for screen time, Damour, who wrote the bestselling book, "Untangled: Guiding Teenage Girls Through the Seven Transitions into Adulthood," recommended parents prioritize what they're trying to protect.

"So we're trying to protect sleep. We're trying to protect family time. We're trying to protect focus. So I think the guidelines should flow from there," she said. "Children need a lot more sleep than people appreciate. Elementary school children need 11 hours a night, middle schoolers need 10 hours a night. High schoolers need 9 hours a night. So if we even do that, that's one heck of a guideline."

The American Academy of Pediatrics recommends avoiding screen time other than video chatting for children younger than 18 months. For children between 2 to 5 years old, the group recommends limiting screen time to one hour per day with "high-quality programs."

On February 12, Damour is releasing her latest book, "Under Pressure: Confronting the Epidemic of Stress and Anxiety in Girls." She said causal data doesn't exist on how social media contributes to anxiety and depression, "but what we do have are some longitudinal studies that have actually looked at the trajectory through sleep."

She explained, "When high schoolers get phones that disrupt their sleep, subsequent they go on to have higher rates of depression, higher rates of emotional fragility."

Social media is just one element of the "broad scope" of factors parents need to consider that may be causing stress and anxiety for kids, she said.