ScienceAlert said that the difference in cognitive abilities was a small one and isn't enough to show a causal relationship, it is enough to be notable.

The study was careful to factor in variables including differences in genetics and the child's socio-economic background. Meanwhile, watching TV and using social media didn't seem to have a positive or negative effect on intelligence. The research should prove useful in the debate over how much screen time is suitable for young minds.

The researchers looked at screen time records for 9,855 kids in the ABCD Study, all in the US and aged 9 or 10.

On average, the youngsters reported spending 2.5 hours a day watching TV or online videos, an hour playing video games, and half an hour socialising over the internet.

Researchers then accessed data for more than 5,000 of those children two years later. Over the intervening period, those in the study who reported spending more time than the norm on video games saw an increase of 2.5 IQ points above the average rise. The IQ point increase was based on the kids' performance on tasks that included reading comprehension, visual-spatial processing, and a task focused on memory, flexible thinking, and self-control.

The report notes that the study "only looked at children in the US and did not differentiate between video game types (mobile versus console games)."