Social-media use and television time have been connected to depression in tweens and teens for a while now—but a new finding suggests not all screen time is a downer....

How: Researchers studied 3,826 adolescents entering seventh grade, almost evenly split between boys and girls, over the course of four years in the greater Montreal area. The study, led by Patricia Conrod at Université de Montréal and published in JAMA, looked at how self-reports of depressive behavior correlated with using four types of screens: computer, social media, television, and video games.

Isn’t that old news? Yes. But what’s surprising about the study is that it isolates video games as the one form of screen time that is neutral in its effects on teen depression. That could be because video games often don’t depict teens or people, Conrod said. Social media and television, on the other hand, may be associated with drops in self-esteem because of what Conrod called “images of idealized lives,” which lead kids to compare themselves with the glossy, filtered, unrealistic images they’re shown.

Another surprise: Conrod and her team found no evidence that screen time affected weekly physical activity. “This suggested to us that the relationship between television and social media on depression was mediated through content and thoughts, rather than physical activity,” she said.

Is there any type of screen time that is positive? According to Conrod, no.

What’s next? Plenty; this research is still in its infancy. Demographics—how gender, socioeconomics, and previous health factors might play a role in depression from screen time—need to be looked at more closely, Conrod said. Researchers also haven’t yet fully figured out what, exactly, it is about screen time that caused depression. Is it a specific type of image? Are there certain behaviors that put people at risk? Answering these questions won’t be easy, but it could help us live healthier lives.


Facebook’s plan to create a new digital currency will be in the spotlight later this week in Washington, thanks to two high-profile congressional hearings on the schedule. But members of the House of...

The news: Reuters reports that Democratic members of the House Financial Services Committee, which will hold a Libra-focused hearing on Wednesday, have circulated a draft bill  called the Keep Big Tech Out of Finance Act that would ban companies that “mainly offer an online platform service with at least $25 billion in annual revenue” from issuing digital assets. (Facebook generated more than $55 billion in revenue last year.) 

Political messaging: Such a sweeping ban would probably have a hard time getting through Congress. But the point of the proposal may simply be to send a message to Facebook and other tech companies about what they are up against if they really want to create their own money. 

It’s also just the latest pushback against the project from powerful US politicians. Maxine Waters, chair of the same House committee, has already called on Facebook to halt the project until Congress can learn more about it. Even President Donald Trump has publicly expressed opposition to Libra, framing it in recent tweets as a threat to the US dollar. 

In the hot seat: David Marcus, head of Facebook’s blockchain project, will be in for a grilling this week. Before he heads to the House, he’ll sit down with the Senate Banking Committee on Tuesday.

Marcus will be pressed for more details on how Libra will work, from both a financial and technical perspective. He’ll likely have to apologize again for Facebook’s past record on privacy. And he may even have to persuade Congress not to ban big technology companies from creating digital money. No pressure!

Keep up with the fast-moving and sometimes baffling world of cryptocurrencies and blockchains with our weekly newsletter Chain Letter. Subscribe here. It’s free!


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Innovators Under 35 | 2019

It’s part of our ethos that technology can and should be a force for good. In these profiles you’ll find people employing innovative methods to treat disease, to fight online harassment, and to create the next big battery breakthrough.