The Indiana University study, coupled with what we know about conditioning and learning, is not proof that playing video games leads to violence. But it does give us reasonable cause to suspect that children who spend a lot of time firing up their reptilian brains may be more prone to violence - and may be less likely to have self-control.

An extreme example of this occurred when authorities discovered a teenage girl who had been locked up in her bedroom for her entire life. Her parents never spoke to her, never touched her - never even acknowledged her. They kept her alive by sliding trays of food under her door.

When police arrested the parents and rescued the girl, she was 12 years old. She was unable to communicate with words, as she had never spoken or been spoken to. Psychologists tried to teach her to speak, but she couldn’t learn to do it. After running brain scans, they discovered the area of her brain that rules speech had atrophied. Due to lack of use, the neural pathways had collapsed - in this case, irreversibly.

I’m not suggesting that all kids who play violent video games will go nuts and lose their ability to be rational. But the nature of the human brain is clear: Practiced behavior becomes dominant. Functions that are ignored get cut off - sometimes forever.

I’ve never bought my son a video game. Yet they are so popular among his friends, he is still exposed to them. I suspect your children or grandkids are too. And I think there is reason to keep the violent ones away from them as much as you possibly can.

I have one other practical piece of advice for you if your child or grandchild is having a hard time controlling his or her aggression. You might consider a nutritional supplement.

Studies show that omega-3s have the power to reduce aggression and violence. For instance, British researchers gave violent prisoners a fish oil supplement along with their regular daily meals. In a matter of days, the prison guards started to notice a change among those prisoners. The results showed that the group taking the supplement had a 37 percent decrease in violent offenses and  a 26 percent decrease in overall offenses.

Your brain is 60 percent fats, and omega-3 fats are essential for your brain to function properly. Children today suffer from a dramatic omega-3 deficiency. And violent video games just might be making a nutritional deficiency worse.

I give my son a daily teaspoon of cod liver oil as a natural source of omega-3 fats. These days, you can find it without the bad taste of the cod liver oil my grandmother used.