It's come to this: Time spent on the Internet is habit-forming, so much so that Stanford University researcher Elias Aboujaoude has concluded that "potential markers of problematic Internet use seem present in a sizable proportion of adults."

More research should be done to determine if problematic Internet use constitutes a pathological behavior that meets criteria for an independent disorder, Aboujaoude says.

It's a bit of a stretch to think of Internet "addicts" in the same boat as drug addicts, alcoholics or even shopping addicts.

But the common thread of addiction is filling a void, whether emotional, physical or spiritual. It's about escape from pain, monotony or circumstances. It's about making the addiction the No. 1 priority in one's life.

It's a little difficult to make the leap between the image of a heroin addict with a needle stuck in her arm and someone wiling away countless hours writing blogs, Twittering or searching for bargains online.

Few of us have tried the former. Most of us of a certain age and education have done the latter, although most of us wouldn't describe ourselves as addicts.

But it's something to think about, particularly when time spent online begins to affect our social environments or our jobs, as our workday grows longer to accommodate our growing Internet use. A longer workday means less time spent at home, which could potentially harm our relationships.

But problem Internet use is not the sole domain of desk jockeys.

A recent article on the Web site parenting.com says young, new mothers are becoming increasingly addicted to blogs, message boards and virtual living sites such as Second Life.

Addiction specialists attribute this phenomenon to isolation. Social-networking Web sites help young mothers connect and escape. The sites become their havens when they are bored, sad or stressed.

There's probably not a lot of harm with that — in moderation. But as with other addictive behaviors, the problems come when users neglect the important people and institutions in their lives because of their Internet use, or when the users begin to conceal it. A Stanford University national survey found that 9 percent of Internet users attempt to hide their "non-essential Internet use" from loved ones. And 14 percent reported it was hard to stay away from the Internet several days at a time.

In the worst cases, Internet-addict mothers are showing up at treatment centers unwashed, unkempt and using drugs to stay up for more time online.