Link between screen time and autism/ADHD risks: What do the experts say?

A team led by Nagoya University Graduate School of Medicine in Japan has investigated screen time in autistic (ASD) and ADHD children. Screen time refers to the amount of time a person spends on a device with a screen, such as a smartphone, computer, television, or video game system. The researchers found that children with a genetic predisposition to ASD were more likely to use screens for longer periods. Meanwhile, children with ADHD gradually increased their screen time as they grew older, even if their initial screen use time was short.

People are increasingly spending their time looking at the screens of their digital devices. This is especially true for children with neurodevelopmental disorders who tend to use screens for longer periods.

Recognizing this issue, researchers from Nagoya University and Hamamatsu University examined 6.5 million polymorphisms in 437 children’s DNA to determine genetic susceptibility to ASD and ADHD. Next, they calculated a genetic risk index that considers the number and size of the effects of changes in genes associated with ASD/ADHD. This is known as a "polygenic risk score”. The researchers then compared it with the amount of time spent using screens devices among a sample of children aged 18, 32, and 40 months.

They found that children with a higher genetic susceptibility to ASD used devices with screens longer (3 hours a day or 4+ hours a day) from early childhood. They also found that kids with a high genetic risk of ADHD gradually increased their screen time as they grew older.

Reference: Psychiatry Research, DOI 10.1016/j.psychres.2023.115395