A new controversial study supported the idea that video games are harming the kids’ minds. The 2-year research that polled over 3,000 school children in Singapore says that nearly one in ten were video game "addicts," and most were stuck with the problem.

While these kids were more likely to have behavioral problems to begin with, excessive gaming appeared to cause additional mental woes.

"When children became addicted, their depression, anxiety, and social phobias got worse, and their grades dropped," said Douglas A. Gentile, who runs the Media Research Lab at Iowa State University in Ames and worked on the study.

"When they stopped being addicted, their depression, anxiety, and social phobias got better."

He said neither parents nor healthcare providers are paying enough attention to video games' effect on mental health.

"We tend to approach it as 'just' entertainment, or just a game, and forget that entertainment still affects us," he told Reuters Health in an e-mail. "In fact, if it doesn't affect us, we call it 'boring!'"

The researchers didn’t elaborate on how many kids had mental issues but they found that those who played longer hours, were more impulsive or had poorer social skills were at higher risk of getting "addicted" over the 2-year period. Besides, those who did become addicted reported increasing symptoms of depression, anxiety and social phobia.

Gentile said it appeared that unhealthy gaming habits were fueling the kids' mental problems, which then in turn might cause them to up their screen time and so forth. But he acknowledged his research didn't prove that point.

In an earlier U.S. study, he found that children who watched a lot of TV or played a lot of video games had slightly more problems concentrating on school work. However, that study couldn't prove that screen time was at the root of the narrowing attention span, either.

The American Academy of Pediatrics, which published the new study in its journal Pediatrics, recommends limiting children's time in front of computers or TVs to 2 hours daily.

"One thing we have to bear in mind is that children playing video games for 2 to 3 hours a day is normal. It's displaced activities like watching TV," Griffiths said.

Still, he said a small minority of kids probably do suffer from true video game addiction, just as some people are pathological gamblers.