Three-year study suggests social media use could be changing kids' brains

A sophisticated new study has tracked the relationship between early teen social media use and changes in their brains over a three-year period. The novel research found more frequent checking of social media was linked with a greater sensitivity to social rewards, but experts stress the detected brain changes can neither be confirmed as causal or declared harmful from these preliminary findings.

Screens have quickly become so pervasive in modern life it has become quite a challenge for researchers trying to understand what impact they have on our health and development. For a teenager, screen time can mean many different things, from using a laptop for schoolwork to scrolling through Instagram on a smartphone.

So despite some studies rolling all screen time into a single homogenous activity, researchers are starting to separate out different digital behaviors. One interesting study from 2019, for example, found television and social media activity correlated with increased symptoms of depression in teenagers, while video game and computer use had little negative effect.

This new research, from neuroscientists at the University of North Carolina at Chapel Hill, set out to specifically home in on the neurodevelopmental effects of social media use in teenagers. The unique study recruited 169 school students and followed them for three years.

At the beginning of the study each 12-year-old participant was asked how many times they checked their social media feeds each day. Those who checked their socials 15 or more times a day were classified as habitual users. Non-habitual users checked social media less than once a day, while moderate users were in the middle. Over the next three years the participants underwent annual MRI scans during which they played a game designed to trigger brain activity in regions associated with social feedback responses.

The striking findings revealed those children with habitual social media checking behaviors showed greater activity in parts of the brain associated with social anticipation and social rewards. And, over the three-year study period, sensitivity in those brain regions increased.

“The findings suggest that children who grow up checking social media more often are becoming hypersensitive to feedback from their peers,” explained corresponding author Eva Telzer.

Because of the study's narrow focus, Telzer is cautious to stress these findings do not necessarily mean social media is causing harmful changes to an adolescent brain. Not only are the findings unable to ascertain casualty but they may also be simply detecting natural developmental changes in certain children that are neither good nor bad.

"We don't know if this is good or bad – if the brain is adapting in a way that allows teens to navigate and respond to the world they live in, it could be a very good thing," Telzer said to HealthDay. "If it is becoming compulsive and addictive and taking away from their ability to engage in their social world, it could potentially be maladaptive."

Speaking to the New York Times, Jeff Hancock from the Stanford Social Media lab called the new study "very sophisticated," but did suggest it was unclear if social media was causing these specific brain changes. Referencing the chicken and egg problem, Hancock said the study may be detecting the development of certain personality characteristics that make some children more likely to be attracted to frequent social media use in the first place. So instead of social media causing these brain changes the social media use may simply be a reflection of certain characteristics.

"[The researchers could be] picking up on the development of extroversion, and extroverts are more likely to check their social media," Hancock said. “There are people who have a neurological state that means they are more likely to be attracted to checking frequently. We’re not all the same, and we should stop thinking that social media is the same for everyone."

The new study was published in JAMA Pediatrics.

Source: University of North Carolina at Chapel Hill