Young people spend a lot of time playing video games these days.

Whether they're building new worlds on Minecraft, doing battle on Call of Duty, committing mayhem on Grand Theft Auto, or roaming any of the other virtual worlds available to them, video games have transformed the way most spend their free time in recent years. According to the latest Neilsen 360 report, over two-thirds of the U.S. population aged 13 and high now consider themselves gamers and the saturation point has likely not even been reached yet. As for the total amount of time spent playing these games, recent surveys suggest that children aged 12 to 15 spent up to 12.2 hours a week in 2017 alone and this statistic is higher in older teens. Even in younger children between the ages of 3 and 4, the time spent playing video games can average 5.6 hours a week or more.

Given the popularity of game playing, it's hardly surprising that parents and teachers have been worrying about possible harmful effects as well as the long-term impact that video games might have on . While much of this concern has been focused on the often violent content of video games and whether it might lead to greater , other researchers have warned about possible health issues including loss of sleep and reduced social functioning.

But research looking at the impact of video gaming on school achievement has been more controversial. While some studies suggest that intensive video gaming can have a negative effect on school achievement, other studies have shown the exact opposite. Part of the problem with this kind of research is that most of the studies carried out have been cross-sectional making it extremely difficult to make assumptions about cause and effect. In other words, do video games affect school performance or are academic underachievers simply more likely to play video games?

Because of the often conflicting findings of the various studies examining how gaming affected school performance, different hypotheses have been proposed:

the time hypothesis suggests that the time spent playing video games means less time that could be spent on academic activities such as studying and homework. For example, young people who play video games regularly typically spend a third less time on homework than their counterparts who aren't gamers. Still, research comparing academic performance in students who own video game consoles and those who don't have found very little difference in their school performance.

the sleep displacement hypothesis suggests that heavy gamers get less sleep overall than non-gamers. Along with getting fewer hours of sleep overall, the quality of their sleep is often poorer as well. Not only do heavy gamers go to bed later than non-gamers but the physical and emotional arousal produced by intense gaming sessions can reduce the amount of sleep they get and make them generally less alert and more prone to cognitive errors.

similar to the other displacement hypotheses, the hypothesis suggests that prolonged gaming can lead to deficits and increased impulsivity. By taking time away from activities that might help young people develop sustained attention skills (such as studying or homework), gaming can have the opposite effect. There is actually some research to support the link between overall (video gaming, TV watching, and computer use) and greater attention problems though the correlation tends to be moderate.

But not all researchers share this about gaming. Supporters of the cognitive enhancement hypothesis point out that video games are often highly complex and can act as training programs for different cognitive skills. This would mean that regular gaming can lead to significant improvements in attention capacity, visual orientation, and overall .

And, yes, there are some research studies that seem to bear this out. Though these samples used in these studies tend to be fairly small, they have found that regular gamers scored higher than non-gamers on tests of , fluid , and working memory. For young children in particular, the improvements appear even greater than for adult gamers.

So, is video gaming helpful or harmful as far as academic success is concerned? A new article published in the journal Psychology of Popular Media Culture attempts to resolve the controversy with one of the largest studies conducted to date. A team of German researchers led by Timo Gnambs of Johannes Kepler University Linz conducted their research as part of the German National Educational Panel Study (NEPS). Designed to follow a large sample of German students across their entire school careers, the NEPS has been the focus of numerous research studies looking at across the lifespan.

For their own study, Gnambs and his co-authors analyzed questionnaire responses from 3,554 students (56 percent female) across three measurement waves beginning in Grade Nine (Wave 1) and continuing through to Grade 11 (Wave 2) and Grade 13 (Wave 3). In the first wave, students were asked about the amount of time they spent playing: (a) online roleplaying games such as World of Warcraft (b) games of skill or strategy, and (c) other computer or video games played on a normal school day. During the first two waves, students were also asked about their grades in mathematics and German. Students in Grade 9 and 12 then completed achievement tests measuring their actual skill in these subjects. Grade Nine students also completed tests of reasoning ability to be used as a baseline estimate of overall intelligence.

All told, 70 percent of the students sampled reported playing video games at least occasionally while 20 percent or more reported spending two hours a day gaming, even on school nights. As expected, boys spent far more time gaming than girls overall and there were also significant differences in competence scores. While boys tended to outscore girls on tests of mathematical competence, girls were significantly better than boys for reading competence as well as getting better grades in German.

In looking at the overall effect of gaming on academics, Gnambs and his colleagues found clear evidence that prolonged gaming on school nights was associated with poorer grades overall. Though the relationship was modest, the results remained consistent even when taking gender differences into account. When looking at actual competencies however, i.e., mathematical and language ability as measured by achievement tests, there didn't appear to be any link with gaming behavior.

What these results seem to indicate is that much of the hysteria over the academic impact of video gaming on school success is likely misplaced. While gaming does appear to have a negative impact on grades, the effect size, while significant, is still very small. As the authors pointed out in discussing their findings, students playing two hours a day increase the odds of receiving a lower grade in mathematics or language studies two years later by a factor of .8 at best. Even in the most extreme cases in which gamers play up to eight hours a day, the extent to which their grades dropped over time varied only slightly (a factor of .5).

Though these results provide some support for the various displacement hypotheses (and none for the cognitive enhancement hypothesis), more research is still needed to look at other factors such as loss of sleep, reduced social contact, or any of the other possible explanations that have been proposed by researchers. Also, it might be useful to look at different types of games to see if they affect young people in different ways. For example, there are numerous games that have been specifically designed to improve cognitive skills. Could they be more beneficial than action-oriented games in terms of school success?

In closing, this study does suggest that concerns about potential dangers of gaming are likely exaggerated, at least as far as academic achievement goes. Still, much like the long-fought debate over whether video games make children violent, the question of whether video games help or hurt children academically is hardly likely to be settled anytime soon.