Pathological attachment to the Internet and depression are linked, according to a study published August 2 by the Archives of Pediatrics and Adolescent Medicine.

The study, conducted by Lawrence T. Lam, Ph.D. and Zi-Wen Peng, M.Sc., examined 1,041 teens ages 13 to 18 in Guangzhou, China.

They were given a survey to determine if they were addicted to the Internet—using it in an extreme or abnormal manner. Questions on the survey included: “How often do you feel depressed, moody or nervous when you are off-line, which goes away once you are back online?”

The survey identified 62 students as using the Internet in a moderately pathological manner, and two students as being severely at risk. None were depressed.

“Some [teens] spend more than 10 hours a day, they are really problematic users and they show signs and symptoms of addictive behavior … browsing the Internet, playing games,” Lam said. “They can’t get their minds off the Internet, they feel agitated if they don’t get back online after a short period of being away. “

After nine months, the study group was re-assessed for depression, and 84 were categorized as depressed. The rate of depression was 2.5 times higher for those who used the Internet pathologically.

“This result suggests that young people who are initially free of mental health problems but use the Internet pathologically could develop depression as a consequence,” the authors wrote.

This indicates that Internet addiction and depression are linked, though it does not prove that Internet addiction causes depression. It could be that people who are likely to become depressed are also likely to become addicted to the Internet.

This is not the first study to link Internet addiction and depression. In February, researchers at the University of Leeds published the results of a study of 1,319 people ages 16 to 51. They too found that excessive Internet use was associated with depression.

In the Leeds study, those who were classified as addicted to the Internet, through a test, spent a greater proportion of their time online on pornography and gambling sites and in online communities.

The study also found that young people were the most at risk of becoming addicted to the Internet.

In 1998, a similar study concluded that “Addicts in this study used the Internet an average of 38 hours per week for nonacademic or non-employment purposes, which caused detrimental effects such as poor grade performance among students, discord among couples, and reduced work performance among employees” (Kimberly S. Young and Robert C. Rodgers, “The Relationship Between Depression and Internet Addiction”).

The Internet can be a powerful and useful tool. But it can also be a huge time waster, and far worse: a gateway to character-destroying content. Parents should be sure to monitor their children’s Internet use. But even for teens, the Internet can have a major effect on their ability to concentrate and, as these studies point out, their wellbeing. For more information, see our article “The Cyberspace Game of Life.”