I'm not trying to start a "are video games bad?" debate or derail this topic. Obviously I'm a huge gamer myself, so that should clear my position up.
But I do want to say that gaming, especially twitchy response, fast reaction type games, can have an effect on the nervous system - especially in the young who are exposed to a continuous diet. The constant rapid reaction to stimulus can "re-wire" the nervous response. And, for some, leads to an impetuousness that might not have otherwise been there. You're so used to having an *immediate* response to stimulus, and sometimes that stimulus comes from within - from emotion, but the response has been trained to take action right now, with no opportunity for cool down. I've seen it in plenty of youth who spend more time gaming that what (I would say) is healthy.
Not everyone will have these issues, but some nervous systems are more sensitive to inertia than others. And in general, I do believe that the human nervous system wasn't designed to respond to such a flood of input that we are subject to in the modern world, gaming aside.
I do feel for the kid and the father. Every parent's greatest dread is having to bury their child.