FRIDAY, Aug. 19 (HealthDay News) — Violent video games with protagonists that hunt, maim and kill are linked to at least short-term aggressive behaviors in children, according to the first large-scale review of studies on the subject.

While the effects of these highly realistic games over the longer term remain unclear, the impact on kids’ attitudes toward violence is worrisome, researchers say.

“Children and adolescents are becoming desensitized to this very violent content, so it doesn’t surprise them — and they expect to see — blood squirting out of someone when they are shot,” said co-researcher Kevin Kieffer, an assistant professor of psychology at Saint Leo University in San Antonio, Fla.

He and co-researcher Jessica Nicoll, also of Saint Leo, presented their findings Friday at the American Psychological Association annual meeting in Washington, D.C.

The companies study should add fuel to a debate on the appropriateness of the most violent computer games for use by American children.

“There have been a number of court cases — including one we cited in this paper, in Indianapolis — which have struck down the legality of banning video game sales to youth,” Kieffer said.

According to Kieffer, the judge in that 2001 suit “found no compelling evidence” from any particular study that violent video games caused an increase in child aggression that could lead to real violence.

Douglas Lowenstein, president of the Entertainment Software Association, which represents the industry, called the new review “little more than a rehash of old papers repackaged as ‘new findings.’ “

“In truth,” he added, “it is neither new nor comprehensive. It is simply a highly selective review of previous research, much of which has been challenged as either weak, unpersuasive, and flawed by independent sources.”

Lowenstein believes the reviewers ignored studies that contradicted their “preconceived views,” and called the APA’s focus on the paper “predictable given APA’s longstanding support of proposals to regulate video games.”

Kieffer described his and Nicoll’s work as an attempt to review the literature on the subject for recurrent “themes” that might provide more convincing evidence, either pro or con, regarding violent video games’ links to aggression.

They looked at 16 studies that focused on video game use and aggression in children under 18 years of age, all published between 1985 and 2004.

Kieffer said three distinct trends emerged.

“First, we noticed in these studies that individuals who are subjected to violent media and video games tend to act more violent in the short-term,” he said.

For example, one study of more than 600 eighth- and ninth-graders, published in 2004, found that kids with high levels of video game play also had “a greater number of arguments with authority figures such as teachers and were also more likely to be involved in physical altercations with other students,” according to the researchers.

In seo services another study, published in 2002, children who were first given either violent or nonviolent video games to play with were subsequently presented with a “retaliation” activity where they could punish opponents by “blasting” them with a loud noisemaker.

“Participants who had played the violent game displayed more aggression against their opponents in the retaliation portion of the study than participants who played the nonviolent game,” the authors of this latest study noted. Another study found that children who indulged in violent video game-playing were less “helpful” to other children during play.

While these findings support links between violent video game use and short-term aggression, Kieffer said it is too soon to know whether these effects