Anyone with a smartphone knows these devices are devilishly distracting. But can taking a break with smartphones cause brain drain? A new study shows it might, depleting cognitive capacity for challenging work. This is significant news for educators and parents, since most tweens and teens own smartphones; many are on them constantly. If there’s a dumbing down effect from phones, there are implications for learning environments everywhere. 

This new study from Rutgers scientists Terry Kurtzberg and Kang Sanghoon, published in the Journal of Behavioral Addictionsassessed cognitive costs of media during a break from rigorous work. College students tackled the same challenging task  solving word puzzles  but were randomly assigned to different break conditions. All spent the break compiling a grocery list but some used computers, some used paper, and some used cell phones. Then they returned to word puzzles. A control group went without a break.   

What happened? “Participants who took a break on their cell phone took 19 percent longer to do the rest of the task and solved 22 percent fewer problems than did those in the other break conditions combined,” noted Rutgers’ press release. Their brains? Slower. Duller.   

 There’s no ammunition here for an all-out rant on screens: Computers caused no cognitive depletion. But there’s something about that phone. It’s addictive, magnetic, researchers write: “This finding supports the developing theory that people are more cognitively and emotionally attached to their phones than they are to other devices, including other electronic tools such as computers.”    

Findings are relevant for schools. Many have taken steps already to protect dedicated class time, implementing strict policies around personal phone use in class. But this study offers new caution, showing even breaktimes matter. Checking notifications on a smartphone right before a test? Not so smart.   

What could explain phones’ lingering effects? That mechanism isn’t clear; it could be that students are still processing what they saw on the device, says physician and filmmaker Dr. Delaney Ruston. Producer of the award-winning documentary Screenagers, Ruston also launched Away for the Day, encouraging elementary and middle schools to become cell phone-free zones.   

Evidence is on her side. “We know from science that when devices are put away for the day that grades actually improve in the school setting,” Ruston says. She’s also deeply concerned about social-emotional impacts, which she covers in her forthcoming documentary. “Younger kids and middleschoolers are more likely to experience some sort of emotional hit during the day when they have access to a phone … It can set them into a tailspin,” she adds.   

As studies accumulate, the message of digital restraint is resonating. Last year, France banned cell phones in schools for students younger than 15. Schools in the U.S. and elsewhere are choosing to move toward more restrictive policies; some require younger students to put phones completely away during school hours, bell to bell. 

Is the goal to banish all devices? Of course not; there’s ample evidence supporting the strategic use of digital tools in learning environments. But setting phones aside during the school day could help protect younger students’ concentration and well-being. The big idea behind Ruston’s movement, she says, is to share science and experience with young people, helping them become mindful and engaged themselves. An Away for the Day school poster validates kids’ struggle to set phones aside — but raises their sights, saying, “It’s not easy … but it’s worth it.”  

Isn’t that true of many good things requiring restraint? Education, like life, is a long game. Kids need to be present  emotionally and cognitively  to win.

Kristen Blair is a Chapel Hill-based education writer.