With respect, lively, I think you need to watch some of these films/games because some of them are shocking. Many children aren't bothered by them, many are. Venables drawing of a scene from 'Halloween' was deeply disturbing.
Why do you think advertisers pay a small fortune to use the visual media network to display their wares? Because they *know* these images sink deep into the minds of their prospective customers.
Violent images are no different.
If you surround children with violence, be it secret violence in the home from abusive parents or relatives, or be it commercial Corporate Bastard sickening violence, the results will be similar. Those results are de-sensitisation of the child's mind.
It's why children are now so mean to each other, so bullying towards each other, why they film other chldren being horrifically beaten up, then send it to their mates, or put it on Youtube.
Of coure, if some 'expert' researched all of this, then came up with information showing how it was affecting different parts of the brain, turning out the lights in the Sensitised Room and turning ON the lights in the De-Sensitised Room, then many folks would believe it, because THEN they'd have 'scientific evidence' to relate to.
What they can't see is the ACTUAL evidence right in front of their faces, and that the children who don't care, who don't feel, who don't understand that it's wrong to film others being beaten up...
You ask the RSPCA about the upsurge in violence towards animals these days too. They are deeply worried about it..
I'm not saying it's the ONLY contributory factor, but it's one, of many.