The rise of smart phones, tablets, and other mobile technologies has put digital media, quite literally, at the fingertips of today’s youth. Most teens now have ready access to a smartphone, with about half spending the majority of their waking hours texting, checking social media sites, watching videos, or otherwise engaged online .
So, what does this increased access to digital media—along with the instant gratification that it provides—mean for teens’ health and wellbeing? In a two-year study of more than 2,500 high school students in Los Angeles, NIH-funded researchers found that those who consumed the most digital media were also the most likely to develop symptoms of attention-deficit/hyperactivity disorder (ADHD) .
ADHD makes it difficult for a person to pay attention, sit still, or control impulsive behaviors. Symptoms of ADHD often occur in young children, but they can also arise in adolescence or even adulthood.
Earlier studies revealed a modest association between ADHD and the time that teens spend watching television or playing video games . In the study now reported in JAMA, Adam Leventhal at the University of Southern California Keck School of Medicine, Los Angeles, and colleagues wondered how today’s expanded menu of digital media—with their rapid operational speeds, constant mental stimulation, and potential for excessive use—had affected teens.
Leventhal’s team enrolled students at 10 racially diverse Los Angeles high schools to participate in the Happiness & Health Study, a survey-based effort to explore various factors influencing addiction and other behavioral risk factors for disease. The students, aged 15 and 16, completed an initial survey about their recent engagement in 14 popular digital media activities, including texting, visiting social media sites, streaming or downloading music or TV shows, and chatting online.
The students were also surveyed about whether they’d experienced symptoms of ADHD over the past six months. To look for links between digital media use and the onset of new ADHD symptoms, the researchers then asked the approximately 2,600 high school students who initially self-reported no significant symptoms of ADHD to complete additional ADHD surveys every six months. They did so from the start of their sophomore year through the middle of their senior year.
About half indicated that they check social media and send text messages, the most popular media activities, many times per day. Importantly, the researchers found that heavy use of each additional form of digital media increased the possibility that a teen would subsequently experience significant ADHD symptoms.
Overall, 9.5 percent of 114 teens who reported seven high-frequency digital media activities subsequently developed significant ADHD symptoms. Among 51 teens who said they frequently participated in all 14 of the digital media activities evaluated in the study, 10.5 percent later reported new ADHD symptoms. That’s compared to 4.6 percent of teens who reported no high-frequency digital media use at the start of the study.
This study represents a starting point, and there are some potential caveats to the findings. For example, we always have to remember in studies like this that association doesn’t prove causation—it’s possible that these were the teens who would develop ADHD signs anyway, and their increased digital use was an effect, not a cause. Also, 80 percent of participants self-reported heavy use of digital media. But most didn’t develop signs of ADHD. Are there certain types of teens that are more prone to developing symptoms of this troubling condition?
Nevertheless, the findings suggest that the recent rise in popularity of digital technologies could play a role in ADHD. The findings also serve as an important warning for teens, parents, teachers, and others as increasingly stimulating forms of digital media become ever more prevalent in our daily lives.
Adolescence is a time of extraordinary physical, emotional, and intellectual growth, and the more we can learn about the factors that lead to healthy adolescence, the better. The NIH recently released an unprecedented dataset representing thousands of participants in the Adolescent Brain Cognitive Development (ABCD) Study , the largest, long-term study of brain development in children and adolescents in the U.S. The 10-year study is designed to explore how drug use or other experiences, including screen time, affect the adolescent brain. I look forward to the many discoveries sure to come as the data continue to come in, allowing researchers around the world to continue exploring these important questions.
 Teens, Social Media, and Technology 2018. Pew Research Center. 31 May 2018.
 Association of digital media use with subsequent symptoms of attention-deficit/hyperactivity disorder among adolescents. Chaelin K, et al. JAMA. 2018 July 17. ;320(3):255-263.
 Media use and ADHD-related behaviors in children and adolescents: A meta-analysis. Nikkelen SW, Valkenburg PM, Huizinga M, Bushman BJ. Dev Psychol. 2014 Sep;50(9):2228-41.
 NIH releases first dataset from unprecedented study of adolescent brain development. National Institute on Drug Abuse. 2018 February 13.