Are your teens strung out on tech?

Amy Fleetwood was tired of all the fighting. Her daughters seemed caught up in nearly nonstop texting, watching videos and sending Snaps.

She hoped the big screen would show them what their phones' small screens were doing to them. So just before Thanksgiving, she took Martha, 13, and Sarita, 16, to see "Screenagers: Growing Up in the Digital Age," a 68-minute documentary about phone and internet addiction.

In it, filmmaker Dr. Delaney Ruston takes a look at her own family's battles over teen tech addiction, explores how it affects adolescent brains -- and suggests things parents can do. The documentary can be seen only when a person or group hosts a showing followed by a guided discussion. Fleetwood, for example, arranged one for about 100 parents and kids.

"I had to find a framework," says Fleetwood of Columbia City, Washington. "I haven't always been clear on what good rules to establish."

It's not your imagination. Teens really do spend about half of their waking days glued to their phones and tablets. Common Sense Media found that teens spend an average 6 ½ hours a day looking at digital devices and almost nine hours across all media. That's not including screen time in school or for homework.

"Those statistics show that this is a problem that isn't going away anytime soon," says Kristin Wilson, national director for clinical outreach at the Newport Academy, which treats teens for depression, anxiety, substance abuse and other mental health issues. She says about 1 in 5 teens getting treatment at Newport suffers from tech addiction.

We all love the way our phones and tablets can help us find information at the speed of "Hey, Google." And we get a pleasant sense of reward when that little screen delivers what we're after. This feeling triggers the brain to produce dopamine, the chemical telling the brain, "That was fun." Dopamine causes us to seek out food, sex and drugs. It can also lead to addictive behavior -- especially in teens, whose brains are wired to go into dopamine overdrive whenever they learn something new.

"One thing that really helped me to start to be a better parent around this was to learn that the [part of the brain] producing dopamine ... when we get new bits of information and we look at the screens ... is most activated when we're kids and we're teenagers," Ruston told "PBS NewsHour" last year.

In other words, it's not psychological. It's physiological.

Brain drain

In 2015, Common Sense Media (PDF) surveyed 2,600 kids in the US, ages 8 to 18, about their online habits. And it found that most teens spend their days in a continual loop of digital media. They're Instagramming and sending Snaps, watching videos, playing video games and listening to music -- often while doing something else, like homework. In fact, half of the teens surveyed said they use social media while doing homework, 60 percent send texts and 76 percent listen to music. Most said they don't think it hurts their work.

They're wrong.

Dozens of studies and surveys over the years have shown that continually switching between digital devices takes a toll on attention span, comprehension, retention and productivity.

"What's extraordinary about the studies on multitasking is, even though you're doing worse and worse on everything you're doing, you feel as though you're doing better and better," Sherry Turkle, noted sociologist and MIT professor of psychology, says in "Screenagers."

Ruston says, as a physician, she wanted to know more about the effects of so much screen time. So for "Screenagers" she interviewed more than a dozen sociologists and researchers. They include Jan-Marino Ramirez, director of the Center for Integrative Brain Research at Seattle Children's Hospital.

To simulate multitasking between devices, Ramirez's lab exposed young mice to fast-changing sounds and light. "And we found that the ability of these young mice to learn new things was very much compromised," he tells the camera. "It took them three times longer or more to learn how to go through a maze than the nonexposed young mice."

Now what?

Ruston, who had made two films on schizophrenia, didn't have to leave home to hit on her next topic. Her daughter Tessa, then 12, was obsessed with social media and her son Chase, 14, couldn't stop playing video games.

"As a mother, I was feeling totally out of control on what kind of limits I should set," Rushton says.

Lots of parents feel her pain. Trying to curb a teen's digital habits can sometimes feel like walking through a minefield. You know there's going to be an explosion; you're just not sure when. Here's the thing: They can't help it.

That's because the brain's frontal lobe -- responsible for insight, empathy, judgment and impulse control -- isn't fully developed until we're in our 20s. Throw in teenagers' overactive production of dopamine, and you get moody, self-conscious almost-adults who can't control their need to be online. It's why getting angry gets you nowhere.

Neither does cutting them off the internet, says Common Sense Media, citing a 2015 study of 10,000 parents in North America. In it, researchers found that children whose parents "take every opportunity to switch off screens" are most likely to cyberbully, impersonate others online or access porn. Giving teens free rein doesn't help, either.

Balancing act

Namita Brown, of Kensington, California, lets her daughter Gisele go online as long as she needs to for homework, but allows just an hour a day for fun. Enforcing the rule can be tricky, though. Gisele, 11, could be doing homework with her friends on Google Hangouts, but they might also be chatting about YouTube gamer LDShadowLady, a common topic.

"The hard-and-fast rule is always being tested, and I find that somewhat troubling," Brown says.

The problem is, there are no hard-and-fast rules for this stuff. Families have to figure out a balance that works for each teen, instead.

Caroline Knorr suggests parents recalibrate the way they measure screen time.

"Look at the week, instead of the day. That takes stress and pressure off the parents," says Knorr, Common Sense Media's parenting editor. "Start on the mandatory things they have to do [for school] and factor having a healthy digital relationship, like two hours on video games."

Experts also recommend establishing screen-free times and zones. Maybe that's at the dinner table or during a two-hour stretch in the evening. Make sure one of those zones is the bedroom because a phone by the bed is just too tempting. Check in weekly, and suggest some device-free activities for the entire family.

Many experts also suggest drawing up separate contracts for each teen that lay out appropriate online behavior (no bullying, no giving out personal information) and the number of hours they can spend with a device.

Fleetwood hopes contracts with her two daughters will bring some peace at home.

"I want there to be times where we as a family exist without constantly being interrupted by the pings of their phones," she says. "This isn't going to be easy. But we're going to give it a try." 

This story appears in the spring 2017 edition of CNET Magazine. For other magazine stories, click here.

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