If you play a lot of video games, you might be affecting your brain structure in the process. Or, it could be that you play a lot of video games because you have an abnormal brain structure.

Either way, researchers have found a link between an increase in grey matter in a certain portion of the brain and heavy gaming.

Scientists at the Ghent University in Belgium have published their findings in the journal Translational Psychiatry. They looked at the brain activities of 154 teenagers, divided based on how much gaming they do in a typical weeks. One group played at least 9 hours a week, while the other played significantly less.

What they found was that the heavy gamers brains were bigger – in one key area. There was more grey matter in a part of the brain known as the ventral striatum, and area that is associated with emotional behavior. It’s a hotspot for dopamine, and is an area of the brain that has been linked with reward.

The area is believed to be a “core candidate promoting addictive behavior.”

The research also looked a brain changes as the subjects anticipated and then received rewards. Frequent gamers had increased brain activity when they were “given feedback that they were losing.” This is the same kind of brain activity that has been observed in compulsive gamblers – who experience dopamine release when experience similar feedback.

Getting back to my original point, the researchers point out that there’s a chicken and the egg debate going on when it comes to the brain differences. Does the heavy video game playing make the kids’ brains overdevelop in this reward and emotion-oriented area? Or do the kids already have this overdeveloped area, and that led them to want to play video games all the time?

Either way, the study suggests a link between video games and addictive behavior that is backed up by brain differences. The science is interesting, but it’s far from conclusive enough to spawn the “Modern Warfare 3 is turning your kids into drug addicts” type of headline. Cool stuff, though – and it could possibly explain why video games seem like a giant rabbit hole where the more you play to more you want to play.

Bigger brains might not be the only side effect of being a heavy gamer. Research we told you about last week suggested that video games make kids more creative.