Last May, the American Psychiatric Association made the ground-breaking decision to include video game addiction in the Diagnostic and Statistical Manual of Mental Disorders.

This medical recognition of obsessive gaming points to a reality faced by growing numbers of young people today, with 8.5 percent of America's youth addicted to video games, according to a study conducted by Iowa State University.

Numbers like these have left many asking, when does a love of gaming cross the line from harmless pastime to full-fledged addiction?

"I think there's a difference between being a casual gamer and an addict," said Matt Brooks, a sales associate at video game retailer Game Haven. "You have an addiction if you play more than six hours a day, ignore your spouse in order to play or let it interfere with your life in some other significant way."

It's easy to sift out the occasional indulger from the staunch addict, Brooks said.

"We're more of a collector's store, but it's easy to spot the addicts who do come in here," he said. "Usually, they're scruffy looking and pretty unkempt. They look like they haven't left the house in three weeks."

Brooks said he believes these people often resort to compulsive gaming as a form of escapism from the troubles of reality.

"On the positive side, gaming can be a great way to escape the real world and relax your mind, like reading a book," he said. "However, it's only positive if it's temporary. Obsessive gaming is done by people who want to ignore reality completely, and usually that stems from some kind of unhappiness in their life."

Melissa Hamilton, junior in English literature, saw these traits exhibited by her "Call of Duty: Black Ops: Zombies"-obsessed roommate during her sophomore year.

"She had just gone through a messy break up and was pretty depressed," Hamilton said. "Soon, all she wanted to do was play 'Call of Duty' and 'Zelda.' She started skipping class so she could play more and was just glued to the controller. She ended up failing a few classes. It was bad."

Hamilton hypothesized her roommate's sudden addiction to gaming manifested itself as a way to succeed and have control when she couldn't in real life.

"I think after her long-term relationship ended and she started doing badly in school, gaming was a way she could still find success somewhere," Hamilton said. "It was an easy way to have control and see your positive actions immediately reap rewards when the real world got a lot harder."

Gus Webster, junior in business management and avid player of the cult soccer game FIFA, agrees playing video games only becomes detrimental when taken to extreme measures.

"I think (video games) are just another form of entertainment for some people," Webster said. "Whereas some would like to sit down and watch a movie, others will play a video game. When I think of an addict though, I think of someone who just takes it to another level. Like buy a game and beat it all in one night for example."

Webster, whose favorite squad to play for is Bayern Munchen, has experienced first-hand the aggressive obsession displayed by those who have taken gaming to that "other level."

"There are definitely some FIFA addicts out there," he said. "There have been many times where I've played somebody online and beat them, and they will send me a message cussing me out or something because I messed up their progress."

Despite these extreme examples, Webster believes there are positive, practical implications to playing FIFA.

"I enjoy playing FIFA because I feel like it does relate to playing in real life by learning and understanding different ways to play the game," he said. "I think FIFA can attract a broader audience to soccer. I have a friend who didn't follow soccer very much, but he started playing FIFA and it made him want to follow soccer in real life."

Video games can generate similarly positive impacts, as long as their consumption is carefully moderated, Brooks said.

"I think addiction to gaming can go medical, which explains why there are 'World of Warcraft' clinics out there specifically dedicated to curing people from WoW addiction," Brooks said. "Some people see gaming as being such a huge component of their life that it can take over. That's when it becomes a personality disorder."