A new study links social media use to changes in teen brains. Is that a bad thing?

Today’s teens and tweens have never known a world without social media. There are still a lot of open questions about how sites like TikTok and Instagram may shape their development — and stories focusing on the potential negative impacts of social media tend to dominate the news.

But a recent study published in JAMA Pediatrics is the latest in a growing body of research that suggests the relationship that young people have with social media is too complicated to be categorized as simply good or bad.

The study, which tracked 169 middle-school students, aimed “to better understand the links between how often teens check social media and how their brains respond to social feedback over time,” study co-author Maria Teresa Maza, a doctoral student at the Developmental Social Neuroscience Lab at the University of North Carolina, said via an email. The results show that the brains of teens who use social media more frequently show greater sensitivity to social feedback — but it’s not so clear whether that’s a problem.

The study scanned the brains of students from three public middle schools in rural North Carolina over the course of three years, having gathered self-reported data from the students about how many times per day they checked Facebook, Instagram, and Snapchat. While the students were in the scanner, they played a computerized game in which they would anticipate and receive social feedback, which was communicated via images of adolescents with facial expressions that could be positive, negative, or neutral.

“We found that certain regions of the brain showed different sensitivity to this social feedback over those three years, and that this changing sensitivity was different for the group of teens who checked social media habitually and those who did not,” Maza said. In other words, over the course of the study, the teens who checked social media more frequently showed greater activity in the regions of the brain related to motivation, control, and salience — how much a given stimulus stands out to an individual — while playing the game. Meanwhile, their peers who used social media less often became less responsive to social feedback.

The study establishes correlation, not causation, between participants’ neural patterns and their social media behavior. So it’s not clear whether checking these apps more frequently leads to greater sensitivity to feedback, or if young people who are more sensitive to feedback are also more prone to scrolling their social feeds. The study also doesn’t take a position on whether greater sensitivity to social feedback is inherently positive or negative. “Given how individualized social media behaviors and experiences can be, this sensitivity may be helpful for some and less helpful for others,” Maza said.

“For example, an increasing sensitivity to social information might prompt future compulsive social media checking,” she continued. “However, a greater sensitivity and awareness of social feedback — particularly digital feedback — might help teens navigate digital-social spaces better, which may be very important in their increasingly digital worlds.”

Maza said that she and her colleagues are in the process of launching a new study exploring digital media use starting with third- and fourth-graders, with the hope of better understanding the impact of digital media contexts on development.

Nick Allen, professor of psychology at the University of Oregon and director of the university’s Center for Digital Mental Health, said in an interview that the new study is an important one. “When you talk to young people about their experience with social media, it’s actually quite a varied experience,” he said.

Allen is the lead researcher partnering with Google on a study that looks at how smartphones may be affecting our minds and sense of well-being. The study, which is still ongoing, examines not only the potential risks of too much time spent on our mobile devices, but also the ways in which researchers might leverage smartphones to provide mental health support to more people.

Smartphones and social media are not going away, Allen said. “The key question is, how do we shape those technologies to maximize the benefits and minimize the risks?”

Allen said he thinks public education campaigns on social media use among young people, and even curriculums built into schools, could be helpful in the future. For example, as adult content becomes easily accessible for young people through social media, schools may want to have open conversations about sharing or restricting certain content.

“Some of those can be focused on kids, some of those can be focused on parents,” he said.

Other research suggests that many young people are already finding ways to use social media to manage their mental well-being. In a 2020 survey conducted by the nonprofits Hopelab and Common Sense as well as the California Health Care Foundation, more than 1,500 teens and young adults were asked about how they used digital media during the Covid-19 pandemic. Young people with depression were nearly twice as likely as those without depression to say they used social media almost constantly (34% vs. 18%) — a finding that could, in a vacuum, be interpreted as worrisome.

But the survey also found that 43% of respondents said that using social media actually made them feel better when they’re feeling depressed, stressed, or anxious, while just 17% said that social media made them feel worse. And 26% of people with depression said that social media was “very” important for getting support or advice, up from 11% in an earlier 2018 survey.

“There are aspects of social media usage, including displacement of healthy behaviors such as sleep, exposure to hate speech, and heightened social comparisons, that indeed negatively impact youth well-being,” Hopelab Chief Science Officer Jana Haritatos said via email. “At the same time, we also find that these social platforms serve as an important connector, information source, and support system for many young people, particularly those who may otherwise lack in-person alternatives, such as LGBTQ+ young people.”

Looking ahead, Haritatos said, “an important priority for the next generation of social media research is greater access to objective data” on how young people use platforms, so that researchers don’t rely exclusively on self-reported usage patterns. In addition, Haritatos said, “we need longitudinal research that dives deeper into the associations between young people’s identities and their use of social media platforms.”

In the end, it may turn out that what’s important when it comes to teens’ development is less how much time they spend on social media — and more what they see and experience when they’re online.

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