Emerging research in the field of sedentary behaviour is increasingly studying the effects of screen time as screens have become an integral part of the lives of many Canadian children and adolescents. A new study conducted in the Greater Montreal area has focused on the association between types of screen time and depression among adolescents by analyzing the results of an annual survey conducted over four years among students initially entering the seventh grade. The types of screen time studied were video gaming, television, social media and computer use. Additionally, three common theories explaining the harmful nature of screen time were evaluated and two other factors, self-esteem and exercise, were assessed to further understand the association with depression.
Overall, this study found that symptoms of depression increased over time but that there were different associations with the types of screen time the students engaged in. The key findings were that social media and television use were associated with depression. Social media and television use were also associated with lower self-esteem, which is associated with depression. For computer use, high average levels over the study period were associated with depression but additional computer use beyond that average level within a year was not associated with increased depression. Interestingly, however, no association was found between depression and time spent playing video games.
The hypotheses which could explain these results are the upward social comparison and reinforcing spirals hypotheses. The upward social comparison hypothesis proposes that by continually being reminded of the perceived better lives of others, adolescents may become depressed over time. This correlates with social media and television exposure as they expose adolescents to depictions of the glamourized lives of others. The reinforcing spirals hypothesis suggests that people who are depressed may seek information that is in line with their current thoughts which in turn worsens their condition. A theory which has yet to be tested but may add further evidence to the reinforcing spirals hypothesis, is that social media often uses algorithms to predict content that a user would be interested in. Therefore, adolescents who are depressed and use social media may both seek and be shown, through social media algorithms, more content which worsens their depression.
The third hypothesis that was evaluated to explain the association between screen time and depression is called the displacement hypothesis which suggests that screen time is harmful because it takes up time that could otherwise be spent on healthier activities, such as exercise and time spent with friends. This hypothesis was not validated by these results since it was found that video gaming is not associated with depression, suggesting that it is not the time taken up by screen time that is inherently harmful to mental health, but rather the content of the screen time. A possible explanation is that video gaming is a very social form of screen time wherein most video gamers actually play with another person either online or in person.
The findings of this study are interesting because they showed that certain forms of screen time are more harmful than others, providing evidence that social media and television should be especially closely monitored in adolescents to prevent and reduce depression symptoms. Further research evaluating certain types of social media and television may be helpful to better understand their association to depression.
About the author: Emi Vargatoth is a research student at the Children’s Hospital of Eastern Ontario (CHEO) with the Healthy Active Living and Obesity research group (HALO). She is currently pursuing her studies at the University of Ottawa where she will be entering her second year of medical school during the fall of 2019.