Many parents feel guilty when their children play video games for hours on end. Some even fear that it will make their children less intelligent. And indeed, this is a topic that scientists have been arguing about for years.
In our new study, we investigated how video games affect children’s minds by interviewing and testing more than 5,000 10- to 12-year-olds. And the results, published in Scientific Reports, will be surprising to some.
Children were asked how many hours a day they spent on social media, watching videos or TV, and playing video games. The answer was: many hours. On average, children spent two and a half hours a day watching online videos or TV shows, half an hour socializing online and an hour playing video games.
In total, that’s four hours a day for the average child and six hours for the top 25% – a huge chunk of a child’s free time. And other reports have found that this has increased dramatically over the decades. Screens existed in previous generations, but now they truly define childhood.
Is this a bad thing? Well, it’s complicated. There can be advantages and disadvantages for children’s developing minds. And that may depend on the result you are looking for. For our study, we were specifically interested in the effect of screen time on intelligence – the ability to learn effectively, think rationally, understand complex ideas and adapt to new situations.
Intelligence is an important trait in our lives and highly predictive of a child’s future income, happiness and longevity. In research, it is often measured as performance on a wide range of cognitive tests. For our study, we created an intelligence index from five tasks: two on reading comprehension and vocabulary, one on attention and executive function (which includes working memory, flexible thinking, and self-control), an assessment of visual-spatial processing (like turning objects around in your mind), and one on multitrial learning ability.
This isn’t the first time someone has studied the effect of screens on intelligence, but research has so far produced mixed results. So what’s special this time? The novelty of our study is that we took genes and socioeconomic background into account. Only a few studies so far have considered socioeconomic status (household income, parental education, and neighborhood quality), and none have taken genetic effects into account.
Genes are important because intelligence is highly heritable. If not accounted for, these factors can mask the true effect of screen time on children’s intelligence. For example, children born with certain genes may be more likely to watch TV and independently have learning problems. The genetics lottery is a major confounder in any psychological process, but until recently it was difficult to explain in scientific studies because of the high costs of genome analysis and technological limitations.
The data we used for our study are part of a larger data collection effort in the United States to better understand childhood development: the Adolescent Brain and Cognitive Development project. Our sample was representative of the US in terms of gender, race, ethnicity, and socioeconomic status.
We found that when we asked a ten-year-old how much he played, both watching videos and socializing online were linked to below-average intelligence. Meanwhile, the game was not related to intelligence. These screen time results are in line with previous research. But when we analyzed it further, we found that the game had a positive and significant effect on intelligence.
While kids who played the most video games at age 10 were not, on average, any smarter than kids who didn’t, they showed the biggest gains in intelligence after two years, both in boys and girls. For example, a child who was in the top 17% in terms of hours spent playing games increased his IQ by about 2.5 points more than the average child over two years.
This is evidence of a beneficial and causal effect of video games on intelligence. This result fits with previous smaller studies where participants are randomly assigned to play video games or a control group. Our finding is also in line with parallel lines of studies that suggest that cognitive abilities are not fixed but can be trained – including studies with cognitive training intervention applications.
What about the other two types of screen activities? Social media did not affect the change in intelligence after two years. The many hours of Instagramming and messaging didn’t increase the children’s intelligence, but it wasn’t harmful either. Finally, watching TV and videos online showed a positive effect in one of the analyses, but no effect when parental education was taken into account (as opposed to the broader factor of “socioeconomic status”).
Therefore, this finding must be taken with caution. There is some empirical support that high-quality TV/video content such as Sesame Street has a positive effect on children’s school performance and cognitive abilities. But such results are rare.
When thinking about the implications of these findings, it’s important to keep in mind that there are many other psychological aspects that we haven’t looked at, such as mental health, sleep quality, and exercise. Our results should not be considered a general recommendation for all parents to allow unlimited gaming. But for those parents annoyed by their kids playing video games, now you can feel better knowing that it probably makes them a little smarter.