Jess Berthold, UC San Francisco
Tweens who spend more time on screens have a higher likelihood of developing disruptive behavior disorders, with social media having an especially strong influence, a new UC San Francisco-led study published today in the Journal of Child Psychology and Psychiatry found.
Social media use was most likely to be linked to conduct disorder, while other forms of screen use — such as watching videos and television, playing video games, and texting — were more likely to be associated with oppositional defiant disorder (ODD).
Conduct disorder is characterized by violating others’ basic rights or societal rules with actions such as bullying, vandalism and stealing, while ODD is marked by a pattern of angry or irritable mood, argumentative or defiant behavior, and vindictiveness.
Researchers collected data on screen use, then evaluated for behavior disorders one year later. Each hour of social media was linked with a 62 percent higher prevalence of conduct disorder, while television, video games, video chat, and texting were linked with a 14 percent to 21 percent higher prevalence of ODD.
“Social media platforms can encourage bullying and aggression, which may contribute to the development of conduct disorder in children,” said Jason Nagata, M.D., lead study author and assistant professor of pediatrics at UCSF.
“Children can be exposed to violent content on social media through ads even if they are not searching for it,” said Nagata. “If kids do search for violence, algorithms will feed back even more disturbing content and children can get stuck in cycles of toxicity.”
Watching movies and playing video games, on the other hand, may displace sleep and physical activity as well as reduce social support, he said, which could explain the tie to ODD.
In another recent study, Nagata and colleagues found that adolescents are so attached to their phones — the main vehicle for screen time — that they report losing track of time when using their phone (47.5 percent) and will interrupt whatever they are doing when contacted by phone (31 percent).
A threshold at four hours a day
Prior cross-sectional studies have suggested an association between screen time and behavior disorders but didn’t differentiate between types of screen use or only examined one type, such as video games. The current prospective study examined links between several types of screen time and behavior in a demographically diverse national sample of 11,875 children ages 9 to 11 years old.
Children self-reported hours per day spent on six different screen modalities: viewing/streaming TV shows or movies; watching/streaming videos, such as on YouTube; playing video games; texting; video chatting; and using social media such as Instagram, separately for weekdays and weekend days.
The average amount of screen time was four hours per day, with the most time spent watching/streaming TV shows/movies (1.3 hours on average), playing video games (1.1 hours), and watching/streaming videos (1 hour).
In fact, four hours a day was a threshold, with time above four hours associated with a 69 percent higher prevalence of conduct disorder and a 46 percent higher prevalence of ODD.
“Some guidelines recommend limiting recreational screen time to two hours per day, but this may not be realistic for many teens,” said Nagata. “Exceeding four hours of daily screen time may lead to disruptive behaviors through exposure to harmful content or the development of screen addictions.”
To assess for behavior disorders, researchers asked parents and caregivers to complete the Kiddie Schedule for Affective Disorders and Schizophrenia (KSADS-5), a computerized tool for categorizing child and adolescent mental health concerns, a year after their children had reported screen use. They found 1.9 percent of the children met criteria for new-onset conduct disorder (1.1 percent of girls and 2.8 percent of boys) and 6.3 percent met criteria for new-onset oppositional defiant disorder (4.7 percent of girls and 7.9 percent of boys).
Future research could examine sleep and ADHD as potential mediators between screen use and disruptive behavior disorders, the authors wrote. “Given that the strongest association was between social media and conduct disorder, social media may be the platform to target for preventive interventions,” said Dr. Nagata.
Co-authors: Andrea Garber, Ph.D., R.D. in the UCSF Department of Pediatrics; Kirsten Bibbins-Domingo, M.D., Ph.D. in the UCSF Department of Epidemiology and Biostatistics; and UCSF medical students Jonathan Chu and Puja Iyer contributed to this research. Please refer to the paper for additional co-authors.
Funding: Please refer to the paper for full disclosures.