Traditionally, there has been some association between screen time (time spent looking at the screens of digital devices such as televisions, tablets, and smartphones) and neurodevelopmental disorders (autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), etc.). has been reported, but the context of this is not clear: ``Is screen time a cause or a result of neurodevelopmental disorders?''This time, a research team from Nagoya University, Hamamatsu University School of Medicine, and Osaka University revealed that the genetic risk of ASD/ADHD is related to the length of screen time.
This study was conducted on 18 children aged 40 to 437 months who were enrolled in the Hamamatsu Mother-Child Birth Cohort Study (HBC Study). We examined the relationship between the polygenic risk score, which quantifies the likelihood of developing ASD/ADHD, and screen time obtained from parents.
First, we found that children's screen time can be divided into the following four groups depending on the progress of their screen time. ① Group 4: “About 1 hour a day (1%),” ② Group 1: “Gradually increase from about 27.9 hours (2%),” ③ Group 2: “Continue for about 19.0 hours a day (3%),” ④Group 1 “More than 3 hours from the beginning (20.3%)”.Furthermore, compared to children without the same risk, children with a high genetic risk of ASD have a 4 times higher risk of belonging to group 4, a 32.8 times higher risk of belonging to group 3, and spend a lot of screen time from the beginning. It turns out that there is a trend.On the other hand, children with a high genetic risk for ADHD were more likely to fall into group 1.5, and although their screen time did not start out high, they tended to gradually increase their screen time.
These results suggest that children's screen time is not the cause of ASD/ADHD, but rather an early sign of ASD related to their constitution.Children with a genetic predisposition to ADHD may spend more screen time, so it's important to make early commitments to digital devices.
In the future, it will be necessary to verify whether these results are replicated in other age groups of children and adults.
Paper information:【Psychiatry Research】The association between screen time and genetic risks for neurodevelopmental disorders in children
