The debate over how much in-game ad spending will rise or fall this year continues, but it’s clear that people—and the advertisers trying to reach them—continue to flock to casual games. And since roughly three-quarters of all sites within MTV Networks now have a casual gaming channel, you could say that the company knows a bit about how to make casual games (and the ads running in and around them) appealing. But what about making them effective?

Recently, MTVN (NYSE: VIA) conducted a three-day study of more than 60 gamers at a biometrics lab in Las Vegas; they showed the players various ads and games, all while examining stats like heart rate, respiration, movement patterns and visual attention. Interestingly, they found that 15-second pre-rolls were the most effective way to garner a player’s “focused attention”—beating out 30-second spots, in-game display ads, and even overlays.

Read more of the findings after the jump.

—Don’t interrupt the gameplay: Pre-roll ads commanded up to 85 percent focused attention, MTVN’s study found, meaning that the vast majority of the viewers paid full attention to the ads. However, it should be noted that MTVN did not offer comparisons to other ad formats to see how attention spans varied. Still, the company feels confident enough that 85 perfent focused attention is enough proof that it was better to target players before they actually got involved in the game. And they also learned to keep the ads short. Pre-rolls that were longer than 15-seconds cut “aided recall” by more than half.

“The question we wanted to answer was do ads need to be more disruptive to be effective?” said Jason Witt, GM for MTVN’s Digital Fusion ad unit. “We can always stick a bigger ad in front of somebody. And we found that you don’t have to be more disruptive, by and large. The proof is that 15-second pre-rolls were the most effective.” The study also found that game ads had 8x higher unaided brand awareness over online display ads in general, and fueled a 12x higher intent to purchase.

—Everyone is a gamer: “As a company, this is a really important space for us—even beyond the acquisition of Atom Entertainment and the success of Rock Band,” said Nada Stirratt, MTVN’s EVP of digital ad sales. “From a business standpoint, the notion of gaming is no longer a way that you categorize people, it’s simply a part of entertainment. It’s like moviegoers, it’s a category of behavior. There is no dividing line between ‘moviegoers’ or “non-movie-goers.’ Everybody goes to the movies, so you have to talk about it in degrees, like ‘how many movies do you see?’ Gaming has become very similar. The numbers are invariably high: 80 percent of moms do casual gaming, 7 out of 10 Baby Boomers are into gaming. So for us, the goal is to see what’s the optimal way of connecting to this audience when they’re that rabid and that engaged.”

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