The positive or negative impact of video games on children can usually be counted on to spark a lively debate, but it's not just kids who are playing games and in some cases causing mental health experts to worry.

Researchers and educators at The University of Texas Health Science Center at Houston are examining the virtual world of an online game called Second Life, for both its addictive and educational potential.

In Second Life, created by Linden Lab in 2003, users are able to create an image called an "avatar" by right-clicking and selecting everything from hair color to chin length to muscle tone. The basic level of membership is free and includes training for the avatar to learn how to walk, talk and fly.

This virtual world is populated by islands, created and inhabited by avatars of other users. Clothes, houses and furniture, even body parts, can be purchased using Linden dollars, which can be bought with real money. Avatars can also "marry" other avatars.

Cindy Burkhardt Freeman, assistant professor of clinical nursing at the UT Health Science Center at Houston School of Nursing, has written about massively multiplayer online role playing games (MMORPG) and virtual worlds such as Second Life. She said users should proceed with caution.

"Patients started coming in affected by it," said Freeman, who sees patients in her private practice in The Woodlands. "They didn't come in for thatno one came in for that problembut it would come out in talking."

In her article for the January 2008 issue of The Journal of Nurse Practitioners, Freeman said one of her patients was suffering from depression brought on in part by his wife's addiction to Second Life.

"She was carrying on an affair with a guy on another continent through the game," Freeman said. "It ruined the family. She just got sucked into it. She was away from her family even if she was in the house."

Freeman's story, "Internet Gaming Addiction," was later named No. 1 on the list of the journal's "Top 25 Hottest Articles."

"Work, relationships, responsibilities, and even personal health and hygiene may be neglected by persons who are unable to control the amount of time spent in on-line activities," Freeman wrote. "They may get restless or irritable if they are unable to play. They may sacrifice time from family, friends and work. They may spend increasing amounts of time playing and may totally lose track of the time."

According to a 2006 Stanford study led by Nick Yee, Ph.D., 39 percent of male players and 53 percent of female players said the quality of friendships with their online friends was comparable or better than their real-life friends.

"You can become someone totally different from who you are. If you don't like yourself, you can change that," Freeman said.

The American Medical Association has called for more research on gaming and addictive behaviors. Directives ordered at the 2007 AMA annual meeting included encouraging organizations such as the Centers for Disease Control and Prevention, the National Science Foundation and the National Institutes of Health to fund quality research on the long-term effects of video games.

"This is something that is just coming to be recognized as a problem," Freeman said.

But universities, Fortune 500 companies and nonprofit organizations see a totally different side of Second Life. They are so committed to the virtual world and its possibilities that they have purchased property (with real money) and created buildings.

Cynthia Phelps, Ph.D., assistant professor of Health Informatics at The School of Health Information Sciences at the UT Health Science Center at Houston, studies Second Life as part of her class on "Emerging Technologies for Teaching, Learning and Research." The class is taught in Second Life.

"We're looking at how you can use Second Life for education," Phelps said. "If you needed to teach a class to people in different parts of the world, you could teach it in Second Life, where everyone can show up."

Phelps said the ability to create things in the 3-D space is one of its attractions. On a recent day, her avatar was checking out the Palomar Pomerado West Health campus on Second Life, a virtual copy of the real-life center that will open in 2011 in San Diego.

Second Life can host educational meetings where instructors from around the world come together; virtual emergency rooms where nursing school students can train and retreats for people with disabilities, among many other opportunities.

Mental health experts, meanwhile, will likely continue their debate over whether online gaming's potential for addiction outweigh its positive benefits.