How Habitual Checking of Social Media Changes the Adolescent Brain
Post by Christopher Chen
The takeaway
Social media use has become nearly universal among American teenagers but its possible effects on adolescent brain development remain unclear. A new study indicates that habitual checking of social media may be disrupting the normal development of brain circuits linked to reward processing and cognitive control in the young adult brain.
What's the science?
The brain undergoes drastic changes during adolescence, particularly in regions associated with motivation, reward processing, and cognitive control. Furthermore, the maturation of these regions allows for developmentally normative neural and behavioral responses to social feedback. With its use of immediate feedback in the form of “likes” or notifications as well as its widespread use in adolescent populations, exploring how habitual social media use affects social feedback-based networks in the adolescent brain is more relevant than ever. In a recent article in JAMA Pediatrics, Maza et al. investigate differences in brain activity levels in regions associated with social feedback in adolescents who habitually check social media.
How did they do it?
The experiment looked at approximately 200 students aged 12-13 from three middle schools in rural North Carolina. First, experimenters had the students self-report how often they checked three social media sites (Facebook, Instagram, and Snapchat). Based on this data, the participants were divided into three groups based on their rate of checking social media: habitual, moderate, and non habitual. Experimenters then used functional brain imaging (fMRI) to measure brain activity of participants during a Social Incentive Delay task, a cognitive task designed to measure anticipation of social feedback. Following initial measurements, the students took part in the same experiment each year for the next two years.
Following the completion of the study, experimenters compiled and combined data from both the Social Incentive Delay task and fMRI imaging to measure activation levels of specific brain regions from each participant during the cognitive task. They then used these individual datasets to make a general linear regression model measuring the change in brain activity levels in all three groups over time.
What did they find?
From their generalized linear regression models, experimenters found that brain activation patterns were significantly different in habitual and non habitual checkers of social media. Interestingly, these patterns were most distinct in brain regions linked to social feedback: the insular and prefrontal cortex, ventral striatum, and amygdala. Habitual social media checkers showed a decreased sensitivity to social anticipation at 12 years of age.
In habitual checkers of social media, linear regression models revealed an increase in brain activity during social anticipation across all four brain regions over time. In non habitual and moderate checkers of social media, linear regression models revealed the opposite: brain activity decreased in all four regions. These divergent results in brain activity changes in habitual and non habitual checkers of social media suggest high social media usage impacts developmental trajectories of neural circuits linked to social feedback and cognitive control.
What's the impact?
The negative functional consequences – if any – of these increases in brain activity in habitual checkers of social media are unclear. Whether the rate of social media usage directly causes or is simply correlated to these neurological changes also remains to be seen. However, this study is the first to show distinct differences in brain development in adolescents who habitually check social media, suggesting that social media is indeed changing the young adult brain.