A new report finds younger children are increasingly exposed to violence in movies.

Movie theater
Flickr user: Bob B. Brown

A study in the journal, Pediatrics, finds gun violence in PG-13 films has increased 300 percent over the past 18 years, and overall violence in motion pictures has nearly quadrupled since the 1950s.

"The trend is very disturbing because it means young children are being routinely exposed to hardcore violence and death. It's baffling, we're worried about school violence and how to protect our children, and then, on the other hand, we allow them to be exposed to all this kind of violence," said child psychologist Dr. Steven Tobias.

He pointed out this desensitizes kids to violence.

"Like this is okay, or killing people is entertaining, and it may also give kids ideas," Tobias said. "I mean, why are we seeing so much random violence and shooting in this country? When you put ideas into kids heads, we shouldn't be surprised when they act on it."

Tobias said the problem carries over to violent video games as well.

"Whether they're aliens or zombies or whatever, it still is teaching that culture of violence," he said. "I don't understand why parents are allowing their kids to do this - other than the fact that their argument is everybody else is doing it, and I don't want my kid to be left out."

He added only a very small percentage of kids actually get tipped over the line and become seriously violent, and although there are other factors at play here -we can't blame violent movies or the video game industry for causing this violence.

"But it does speak to the culture and values that we have as a society. If our kids are surrounded by violence in movies and games, the question then becomes what are they not learning, what are the values that they're not demonstrating - what are they not practicing? They're not practicing kindness, caring, empathy, giving towards others."

The bottom line, said Dr. Tobias, is that "whatever you spend your time doing is what you learn.

"If you're focused on violence, you're not learning about co-existence."