Putting advertising into video games might seem like a great way to reach an attentive audience, but a recent study reveals a counterintuitive relationship between in-game violence and the impact of advertising.

A team of European and U.S. researchers found ads displayed along with violent scenes to be more memorable to players than those shown with nonviolent content, even though players spent less time looking at them. The results are contrary to expectations stemming from research on television, where violence has been shown to decrease attention to advertisements. Developing a better understanding of the way advertising works in games could help game companies enhance their advertising strategies.

André Melzer from the University of Luxemburg and colleagues developed a simple racing game called AdRacer to test the way violence affects a player’s response to in-game advertising. A player drives around a virtual course and scores points by hitting targets along the way–as she drives, unobtrusive graphical ads are displayed as billboard graphics on the side of the track, while a camera records her eye movements. After playing, each player’s ability to recall of brands shown on the side of the road was tested.

Those who played a violent version of the game, where the goal was to run down pedestrians, resulting in a blood-splattered screen, demonstrated significantly better recall of advertised brands than those who played the regular version. The researchers presented their work at the International Conference on Entertainment Computing last year.

The in-game advertising industry is predicted to grow rapidly, with PricewaterhouseCoopers suggesting it’ll be worth $1.4 billion in 2013, up from an around $886 million this year. Even so, some companies have struggled to make enough money from in-game advertising. This month game company id Software, announced that a previously ad-supported game called Quake Live would become subscription supported because advertising had failed to generate enough revenue.

Jonathan Epstein, CEO of Double Fusion, a company that sells in-game ad technology, says new strategies are needed to help the industry grow. “Continued innovation in ad units will help provide more options for the different types of buyers trying to reach the gaming audience.”

One problem for in-game marketing is that players can get frustrated if advertisements impede play. Double Fusion discovered this when it recently tried to introduce in-game advertising to Sony’s Wipeout game. The companies had to abandon the plan when players complained about extended ad sequences that displayed before playing, resulted in slow load times.

The in-game advertising industry relies on pre- or post-roll videos, or prominently placed billboard graphics that are sold on a per-view basis. Melzer says his research points to the need to better understand what makes game ads memorable. The industry generally tracks in-game ad effectiveness only through a combination of research surveys and geographic data recorded during game play, but, Melzer says, “it will be necessary also to analyze the mechanisms that underlie memory performance.”

Immersive systems such as AdRacer may be instrumental for testing prelaunch games for effectiveness, and subtler advertisements integrated into games may be a more effective way of reaching players. One approach is to place products as digital objects that can be interacted with. “The market is moving beyond graphic ads to more complex animated and video ads–to 3-D object advertising,” says Epstein, noting that new car models can, for instance, be placed prominently within a game.

Research published this month in the International Journal of Advertising backs up this claim. A team led by Thomas Mackay from Monash University in Australia found that driving a virtual car of a specific brand resulted in a significant opinion change in favor of the brand among casual game players.

Some brands may also want to steer clear of advertising in violent video games to protect their public image. “Attempts to increase players’ familiarity with brands by integrating them in a violent game may backfire at in-game advertisers and video game producers,” Melzer says. Double Fusion’s Epstein adds that “even if it were shown that violent games have better recall characteristics than nonviolent games, it is likely that the same brands would continue to eschew M-rated [mature] opportunities in favor of the 80-plus percent of games that are rated T [teen] or below.”

An unreleased follow-up study by Melzer reveals another undesirable result: that violent play can negatively impact a player’s opinion of a brand.