In the study titled, “Differential Psychological Impact of Internet Exposure on Internet Addicts," published online in the international journal PLoS ONE , Professor Phil Reed of Swansea University’s Psychology Department, Dr Lisa A Osborne of the University’s College of Medicine, Professor Roberto Truzoli and Michela Romano of the Università degli Studi in Milan, reported results of their research study on the negative psychological impacts of heavy Internet use.The researchers found that people who habitually surf the Internet for long periods at a time suffer higher incidence of "negative moods" after they stopped surfing, leading to addiction-like urge to return to the Web to alleviate or lift the negative mental states. The researchers warned that surfing the Internet for long stretches of time can result in withdrawal symptoms similar to those that drug abusers experience.The researchers said the results could mean that serious mental health issues may arise if, as anticipated, more people spend more time online in the future.According to Professor Phil Reed : “Although we do not know exactly what Internet addiction is, our results show that around half of the young people we studied spend so much time on the net that it has negative consequences for the rest of their lives. When these people come off-line, they suffer increased negative mood – just like people coming off illegal drugs like ecstasy. These initial results, and related studies of brain function, suggest that there are some nasty surprises lurking on the net for people’s well-being."The study claims to be the first of its kind on the negative mental health effects of heavy Internet use. It was carried out at Swansea's University College of Human and Health Sciences using 60 volunteers with an average age of 25.The volunteers were given psychological tests to measure their levels of "Internet addiction," mood, anxiety and depression. They were then required to browse for 15 minutes, after which they were tested again for mood and anxiety levels.The study concluded from the results obtained: "The negative impact of excessive Internet use can be seen across a wide range of aspects of the addict’s life. Internet addiction was associated with long-standing depression, impulsive non-conformity, and autism traits."The study authors concluded that Internet use had a "striking" effect on positive moods of individuals "addicted" to the web, and that such persons suffer more severe withdrawal symptoms than people who spend less time online.The study authors noted the condition may lead to a vicious cycle: "The immediate negative impact of exposure to the Internet on the mood of Internet addicts may contribute to increased usage by those individuals attempting to reduce their low mood by re-engaging rapidly in Internet use."The authors said that results also showed that heavy Internet-users tend more to depression and have higher indications of autism traits.Reed said : "These results corroborate previous reports regarding the psychological characteristics and traits of Internet users, but go beyond those findings to show the immediate effect of the Internet on the mood of those who are addicted."