Internet addiction may be one of those phenomena that at first will be understood better clinically than empirically. In fact, many of those studying Internet misuse were lured into such research after a client showed up at their doorstep with problems related to Internet overuse.

A case in point is Keith Anderson, PhD, staff psychologist at the student counseling center at Rensselaer Polytechnic Institute. A young man whose grades had suddenly plummeted entered counseling, and he told Anderson he was depressed, having sleep problems and warring with his parents. When Anderson probed further, the young man admitted spending 2,000 hours that semester joining "multi-user dungeons," games that can include hundreds of online players.

"The kid didn't know the students who lived next door to him, but he went down to visit someone in Tennessee who he met online," Anderson said.

That case prompted him to survey 1,300 students at eight academic institutions on their computer-use habits. About 10 percent of his sample met his criteria for Internet dependency, which he had adapted from criteria for drug dependency. Most of the heavy users were male and in the hard sciences.

"In many ways, we've brought a Pandora's box that otherwise wouldn't have been there into our schools, into our lives," asserts Kimberly Young, PhD, of the Center for On-line Addiction in Bradford, Pa.

She says clinicians can't wait for the perfect data before they start treating people. Of the 35 therapists she recently surveyed in a study in the October issue of CyberPsychology & Behavior, 80 percent reported a rise in the number of clients with Internet-related problems over the last year, Young said.

To that end, psychologists are crafting therapy techniques based on cognitive-behavioral treatments for other compulsive behavior problems, such as eating disorders and gambling addiction.

"Whether it's an addiction, a symptom or a new tool," says Maressa Hecht Orzack of McLean Hospital's Computer Addiction Service, "something is happening and it needs to be treated."