Over winter break last year, sociologist Tom Brignall became someone he barely recognized, a man in pursuit of a new addiction — online gaming.

"On some days I barely ate, drank or left the house," Brignall says.

In the name of participant observation research, the assistant professor joined the more than 3.5 million online gamers playing "World of Warcraft." The game is one of a growing industry of games known as MMORPGs or massive multiplayer online role-playing games.

"In order to study the diehards, I became one of them," says Brignall. "I spent 12-14 hours per day, seven days a week, playing the game during Christmas break. I had planned to play for only a couple of hours a day for a few days a week.

"However, I soon realized in order to study hard-core gamers I needed to become one. At one point, I found myself getting up at 6 a.m. and playing into the evening. One day, I realized I'd played 18 hours with no food or sleep, and only a few bathroom breaks. I realized I eventually had to quit cold turkey or I would never get anything else accomplished."

Brignall’s experience only fanned the flame of his interest in conducting further research. He has submitted a book chapter describing interviews with people who spend at least 20-30 hours per week playing MMORPGs. They buy software ranging from $25 to $50 and pay about $15 a month to access fantasy worlds.

Once there, they mimic and expand almost every real-world experience imaginable. They hang out in cities, fight battles, hunt animals, trade items and traverse the globe. A half million subscribers pay Sony $13 a month to play Everquest, and there are numerous other popular games, including Dark and Light, Guild Wars and City of Villains.

"I'm a little concerned that this is a primary form of socialization for some players," he said. "I found some players who ignored the adventure and just showed up to hang out at the bar." (Some "virtual worlds" include the kinds of settings found in any town or city, including bars.)

Brignall says many camps emphasize the positives of time spent in a virtual world. Players experience adventure, companions and decisions they would never experience in real life. But as a sociology professor, Brignall is wary of such a rosy picture.

"I'm not sure; I'm still deciding," he says. "As in life, there is the sour and the sweet. I encountered a significant amount of overtly displayed ethnocentrism, discrimination, neo-tribalism, and aggressive behavior while playing the game compared to everyday encounters. Perhaps this is due to the anonymity, the age of some players, or the lack of social repercussions."

He's not the only one concerned about what happens when the online experience is taken to the extreme. Warcraft's parent company announced earlier this year that it had become the largest MMORPG in the world, with more than 1.5 million paying customers in China alone.

About the same time, Beijing officials introduced an anti-addiction system designed to protect players' mental and physical health by nagging them to log off if they play beyond a "healthy" time-limit of three consecutive hours. A young Korean made headlines in August when he died of heart failure caused by apparent exhaustion after playing an online game for more than 50 hours nonstop.

"I think it's the romantic notion of being the last world of conquering," explains Brignall. "Everything's new. And life seems to go faster within the game. It's like when kids see Christmas finally come, and everything seems to go so fast that you just can't get enough of it."

Previous studies on player archetypes seem accurate, says Brignall, who cites the work of researcher Nick Yee. There are several players who "go for the win," bullies, explorers, leaders, socializers, and players who just want to help others. Brignall says he'd like to find out whether these are the roles players take on in their real lives, or if they take on new personas online.

Brignall describes each game as a launching pad that gives millions a shared experience. He says he has met enough people who did not fit the typical stereotypes to be convinced that the games are growing increasingly attractive across age groups and professions.

"Assuming people were telling me the truth, I met a lot of older people, 40 to 50 year olds," he says. "And I met five or six guys who had Ph.D.s."

Brignall looks forward to delving even further into the motivations and consequences associated with online gaming.

"I wonder if it's a response to a lack of public spaces to gather and socialize that draws so many people into playing the games," he says. "I wonder if players perceive themselves as addicted. There are still a lot of unanswered questions."