Our son is now at the age where we let him watch a moderate amount of children's videos to entertain himself -- all firmly G rated stuff.
I have also been allowing him to watch some recent animated features such as Cloudy With a Chance of Meatballs (PG) and Megamind (PG) and the Incredibles (PG), with mild levels of cartoon / action violence.
I also rented some classic "Looney Tunes" and "Tom and Jerry" cartoons, remembering how much I enjoyed them as a child. But after auditioning a few, I was kind of shocked how much actual, real cartoon violence they contain, and I quickly backed off those. You see where Groening got his inspiration for the Itchy and Scratchy parody from, it's shocking how violent old cartoons really are!
However, even at the MPAA PG level, I am worried that I might be exposing my son to too much cartoon violence, and I am concerned what effects it might have.
Should I be concerned? Is there any research documenting the effect on children in the 2-4 year age range of watching a moderate amount of G-rated children's videos versus a moderate amount of PG-rated children's videos?
(Note that I am not asking for the effect of no video, just how risky is it, per any published research on the matter, to deviate from moderate amounts of children's videos at G versus PG)