There is such a thing as internet addiction - and it changes victims' brains, according to a Chinese team of researchers.
Hao Lei of the Chinese Academy of Sciences in Wuhan and his team studied the brains of 18 'internet addicts' and a similar-sized control group and discovered differences between the two.
The internet addicts were ideitified on the basis of a questionnaire asking questions such as "Have you repeatedly made unsuccessful efforts to control, cut back or stop internet use?"
And, through an MRI scan, those who said yes were found to have changes in the white matter of the brain. Disruption to connections in nerve fibres linking brain areas involved in emotions, attention, decision making and self-control was found.
There are two obvious question marks hanging over the study. First, it's a very small sample group; and secondly, there's no way of telling what's cause and what's effect.
Maybe overuse of the internet is affecting brain structure; or maybe people with poor decision-making skills and low self-control are more likely to become internet addicts.
"Overall, our findings indicate that IAD has abnormal white matter integrity in brain regions involving emotional generation and processing, executive attention, decision making and cognitive control," the researchers write in PLoS One.
"The results also suggest that IAD may share psychological and neural mechanisms with other types of substance addiction and impulse control disorders."
They say the findings could be useful in coming up with ways to identify and treat internet addiction.