APA 2009: Functional MRI Reveals Neural Correlates of Internet Addiction

Susan Jeffrey

May 21, 2009

May 19, 2009 (San Francisco) — Although it is not yet considered an official diagnosis, Korean researchers have found neurophysiologic differences in brain activation on functional MRI between subjects who participate in a Internet-addiction support group and controls.

"This means that there are neurophysiologic differences, not just behavioral differences, between these 2 groups," lead author Hyoung-Yoon Chang, MD, from the National Health Insurance Corporation in Seoul, South Korea, told Medscape Psychiatry.

Their findings begin to provide a basis to argue that Internet addiction be made a standard diagnosis in the upcoming fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), she said. "Internet game addiction should be included, and there should be treatment for this disorder."

The results were presented here at the American Psychiatric Association 162nd Annual Meeting.

Growing Problem

Internet game addiction is a growing problem worldwide, the researchers write, and new multiplayer online role-playing games such as World of Warcraft (Blizzard) are thought to have an even higher addictive potential.

However, Dr. Chang said, Internet addiction is not currently a validated disease entity with established diagnostic criteria. "But I think it's really needed, because there are a lot of people with this problem seeking treatment."

In this study, she and colleagues sought to outline any physiologic differences in response to game playing between 12 members of an Internet addiction group and 12 normal controls, using functional magnetic resonance imaging (fMRI).

Participants in the support group met criteria for Internet game addiction using Young's Internet Addiction Scale; they were a mean of about 23 years old and played an average of 8 hours per day. The control subjects, deemed casual Internet players, were matched for age but played video games an average of 3 hours per day. None of the subjects had any history of psychiatric or neurologic disorders.

Scans were taken while the participants watched a video screen showing World of Warcraft characters in either a fighting state or in a resting state. They found significant between-group differences on fMRI at the medial, superior, and interior frontal gyrus of the left hemisphere, but only when comparing the fighting state with the resting state of the game.

"There was a significant difference in the frontal lobe, but the difference wasn't found when the fighting stage was directly compared with the resting stage. However, there was a significant difference when activation during the fighting state was subtracted from the resting stage," Dr. Chang explained.

The addiction group showed a smaller difference between the fighting state and the resting state. "They are already sensitized to that fighting stimuli, so there's not as much difference between the fighting state and the resting state, or that's what we think," she noted.

Addiction is thought to be related to reward pathways and dopamine, she noted, but their observation of differences in the frontal lobe does not correlate with this hypothesis. "We're still trying to find the underlying neurophysiologic pathology for Internet game addiction so we can build on it," she concluded.

The researchers hope to replicate their findings with a larger sample.

Internet Addiction Established by Behavior

Asked for some perspective on these findings by Medscape Psychiatry, Mark L. Willenbring, MD, director of treatment and recovery research at the National Institute for Alcohol Abuse and Alcoholism at the National Institutes of Health, was not convinced of the need to establish Internet addiction as a bona fide disorder.

"Of course it's an addiction," he said. "They're playing video games 8 hours a day. We don't need to scan their brains to know that something is wrong."

What fMRI can do in this instance is show similar patterns between this addiction and other disorders and may indicate areas such as in this study, the prefrontal gyrus, that are at least potentially involved in this particular addiction, he added. "So it's useful, but it doesn't tell us much."

The activation shown by fMRI is only relative to surrounding areas, Dr. Willenbring pointed out. "It could indicate a busy intersection between the areas of the brain that are communicating but aren't themselves being activated, so it's very complicated."

Link to Depression

A second abstract, also from Korean researchers, with first author Jung Eun Jung, MD, from Daegu Daedong Hospital in Daegu, South Korea, reports a significant positive correlation between depression in adolescents and Internet addiction.

In a sample of 53 adolescents with depressive mood disorder, 36, or almost 68%, were found to have Internet addiction using the Anxiety Rating Scale, Korean version (ARS-K). The prevalence of Internet addiction did not vary by sex, they note.

"It seems to be crucial to include questions about Internet usage in psychiatric examination taking," the researchers conclude. "Future studies should investigate the direct relationship between psychological health problems and Internet dependency."

The authors have no relevant financial disclosures.

American Psychiatric Association 162nd Annual Meeting: Abstracts NR5-069, NR3-045. Presented May 18, 2009.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.