Caroline Watson, lead researcherAdolescents who engage in consistently high levels of digital media use may face increased risks to cognitive health and safety later in life, according to new research led by investigators at the University of Alabama at Birmingham Marnix E. Heersink School of Medicine.
The longitudinal study, published in Children, found that young adults who had sustained high levels of digital media use during adolescence were more likely to report suicide attempts and performed worse on short‑term memory tasks in adulthood compared with peers with low screen use.
While past literature has focused on the effects of digital media use on mental health measured at a single point in time, these findings explore long‑term impacts of digital exposure.
“Much of the conversation around adolescent screen time focuses on how many hours teens spend on devices today,” said Caroline Watson, a clinical psychology doctoral candidate in the Department of Psychiatry and Behavioral Neurobiology. “Our findings suggest that it’s the cumulative pattern of heavy use across adolescence that matters more for certain outcomes later in life.”
The study analyzed data from more than 6,700 participants in the National Longitudinal Study of Adolescent to Adult Health, a nationally representative, federally funded dataset that followed adolescents from middle and high school into young adulthood.
Using advanced statistical modeling, researchers identified four distinct patterns of digital media use from ages 11 to 30:
- Low use, representing nearly three‑quarters of participants
- Increasing use over time
- Decreasing use, which began high and fell gradually
- Consistently high use, representing less than 3 percent of participants but marked by 40-50 hours of screen time per week across adolescence
Young adults in the consistently high‑use group demonstrated significantly poorer short‑term memory performance. Those in both the high‑use and decreasing‑use groups also had higher rates of reporting a suicide attempt in the past year compared to those in the low‑use group.
The researchers noted that, contrary to some public assumptions, digital media use trajectories did not significantly predict depression diagnoses, anxiety diagnoses, depressive symptoms, suicidal thoughts or memory performance.
“These findings suggest a more nuanced relationship between digital media and mental health than is often portrayed,” Watson said. “Digital media use may be one of several contextual factors influencing development, rather than a direct cause of anxiety or depression.”
The authors say the results raise important questions about how sustained screen exposure during critical developmental periods may affect brain functioning and long‑term well‑being.
“Adolescence is a formative period for brain development and habit formation,” Watson said. “Understanding how long‑term media habits intersect with mental health and cognition is essential as digital media becomes increasingly embedded in daily life.”
What can parents do?
Watson advises parents to consider encouraging healthy, long-term patterns of digital media use beginning at an early age. For example, they can help establish consistent routines around digital media use by setting clear expectations for digital media-free times.
“A consistent routine can look like limiting digital media use before bed or during meals,” Watson said.
Another important action for parents is to model balanced digital media use themselves.
“By being intentional about their own screen time and demonstrating healthy habits, such as putting devices away during conversations or shared family activities, parents can make a huge impact on their children,” Watson said.
According to Watson, parents can benefit from viewing digital media use as one part of a broader developmental picture, rather than the sole driver of outcomes.
“Digital media use may be best considered alongside factors such as sleep, academic demands, peer relationships and the family environment when thinking about mental health and cognitive outcomes,” Watson said.
Data used in the study were collected between 1994 and 2009, before the widespread use of smartphones and social media platforms. The research was supported by the National Institutes of Health.