Girls and boys may be more vulnerable to the negative effects of social media use during specific windows of their adolescence, researchers found after a large longitudinal study.
Tracking the same individuals over the course of a year, researchers at the University of Cambridge, University of Oxford, and Donders Institute for Brain, Cognition and Behaviour found a negative link between social media use and life satisfaction in girls when they’re between 11 and 13 years old, and boys when they’re between 14 and 15 years old.
While social media use didn’t seem as detrimental for the last few years of adolescence, the link between increased social media use and lower life satisfaction reappeared for both girls and boys at 19. At other times in life, the link was not statistically significant.
Though this requires further research, authors suggest the differences in sensitivity to social media could be linked to puberty, which occurs later in boys than in girls. Researchers say it’s possible that life changes, such as leaving home or starting work, may make the 19-year-old cohort vulnerable to a decrease in life satisfaction. They also pointed out that social media sensitivities may be linked to structural changes in the brain.
While most neuroscience research on social media focuses on well-being in general, this study incorporated the specific changes in brain structure and function across the transition from childhood to adulthood. Decreases in brain gray matter volume, or cortical thinning—a sign of brain maturation—continue into the mid-20s.
The longitudinal study looked at specific areas of the brain associated with depression and weak impulse control in adolescents three times over a span of five years. The 189 participants were 10 to 25 years years old, with an average age of 16. This age range is a time of increased emphasis on social connection. Those with low mental well-being included more females (74 percent) than males (26 percent).
According to magnetic resonance imaging results, adolescents with high social media use showed statistically significant differences in baseline cortical thickness in the lateral prefrontal cortex and medial prefrontal cortex areas of the brain—the areas of the brain that allow for social cognitive control of our behavior and actions—and stronger decreases in the lateral prefrontal cortex and temporoparietal junction—the region of the temporal lobe largely responsible for creating and preserving both conscious and long-term memory.
Mental well-being was significantly associated with differences in structural brain development, they found.
“These results suggest that mental well-being and associated brain development might be more inclined to genetic factors, whereas changes in cortical thickness and social media use are possibly more strongly associated with environmental cues,” the authors write.
“Our results show the importance of examining individual differences in brain maturation and provide a starting point to further examine neural mechanisms that could explain which adolescents thrive by social media and which might be harmed.”
