Transcript for What parents should know about the online survival game Fortnite

Amy, you have our "Gma" cover story about a popular video game so many are playing. Video games are facing some new scrutiny this morning. President trump has announced he's meeting with video game executives next week to discuss violent content following the deadly Florida school shooting. This as a new game called fortnite and some parents are worrying their kids are spending too much time at the controls. It's the online game that has fans in a frenzy. Fortnite's objective. Players join teams and battle up to 100 others to be the last person standing. The multiplayer melee drawing comparisons to blockbuster franchise "The hunger games". I volunteer as tribute. Reporter: With millions of users from kids to even celebrities like chance the rapper, Joe Jonas and steelers wide receiver juju smith-schuster caught up in the craze. I'm at this party right now and all I'm thinking about is fortnite. Over 40 million people in America play it. Chances are you know somebody who is enjoying it. Reporter: With the option to buy upgrades and bonus features the company reportedly raking in big bucks off the game's big buzz. It wouldn't surprise me if they were making hundreds of hundreds upon thousands on any day, even millions. Reporter: For some parents its popularity is a cause for concern. I love it. Reporter: Amy says her kids are so caught up in the game she sometimes won't see them for hours after school. They downloaded it around november/december. Around that time I guess that's when they slowly started disappearing. Reporter: She wrote about it in a blog titled have I lost my children to fortnite garnering big response from other parents across the country. Everyone is sort of struggling with the same thing. How much time do we let them actually play this where they're not fighting and they think they've had enough time and I'm not the bad guy. Reporter: It's the only fortnite. This year in a controversial decision, the world health organization officially recognized gaming disorder as a mental health issue. The American academy of pediatrics advises parents to place consistent limits on screen time making sure it doesn't take the place of adequate sleep, Phy activity and other behaviors essential to health. But for worried parents fortnite's social aspect may actually have a positive effect. The beauty of video games is they're moving from being solo experiences to more social experiences that invite people to come together and bond over a shared positive activity. To further the discussion let's bring in clinical sports psychologist Dr. Jonathan fader. And, Jonathan, thanks for joining us. From a clinical perspective what makes this game different than any of the games we've seen before. When you mentioned fortnite there were people high-fiving. I saw a bunch of teenagers high-fiving. This is a viral game. People are so into this game and the thing that makes it so different is it's so interactive, Michael. People can play duo as a team and really interact over the video game. It affects our pleasure centers of the brain. That's what video games do and this one is really intense. So speaking specifically to fortnite, how much playing time is too much, parents want to know. What limits do we set? The American academy of pediatrics says if your kid is 20 to 5 it should be an hour or less a day. With teenagers it's about the context. How does a video game affect their activities. Does it prevent them from getting their schoolwork done or doing other social activities. Homer Simpson had a great quote, to alcohol, the cause and solution to all of life's problems so you know when you think about these video games it's like, yeah, they give kids fun but at the same time let's moderate. Is it hard as a parent to find that balance with your kids. It's so hard. My kids play video games and what I do, I play with them. I want to see what they're doing and want to -- I mean, some of it is just fun but I want to be there and understand how violent it is and also want to help them limit it themselves. It's a problem because my kids use all of those devices for their schoolwork so like, mom, I'm doing schoolwork so I say you have to have a door open and you can't have headphones on. If you hear that play happening, you know. I'm doing my essay, slash doing fortnite. It's a great undercover thing so when you tell a kid put it on airplane mode they can't a lot of times. A lot of schoolwork is interactive doing research on the web. What if, if there are any benefits to playing video game dmrs definitely benefits. The thing about fortnite. Mul multiplayer game and the thing they enjoy about it, you're talking to your friend while doing it. So that's one of the fun parts about it. That's what sucks people in and says, hey, five more minute, ten more minute, three hours more and you can spend your whole life in the family room playing. A lot of kids who aren't connected in sports or other settings find a social scene in that which is as a benefit but in moderation. It can really get out of hand? Moderation being the kye. I like that. You play with your kids so you know what they're doing and time to cut it off. Play with them and find other ways to limit it. What I say is stop telling your kids don't do this. Tell your kids do this, give them the other activities. Give them other things to do. If you're just telling them stop doing that. It's just going to be a drag. Connect with them. Understand what they like about it. All right, Dr. Fader, thanks so much.

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