Impaired risk evaluation in people with Internet gaming disorder: fMRI evidence from a probability discounting task

•We examined the probability discounting rate of IGD at a neural level.•Behavior results indicated the IGD subjects prefer risky options than HC.•This study proved that people with IGD show reduction of risk aversion.•Decreased activation in inferior frontal gyrus and the precentral gyrus were found in IGD.

This study examined how Internet gaming disorder (IGD) subjects modulating reward and risk at a neural level under a probability–discounting task with functional magnetic resonance imaging (fMRI). Behavioral and imaging data were collected from 19 IGD subjects (22.2 ± 3.08 years) and 21 healthy controls (HC, 22.8 ± 3.5 years). Behavior results showed that IGD subjects prefer the probabilistic options to fixed ones and were associated with shorter reaction time, when comparing to HC. The fMRI results revealed that IGD subjects show decreased activation in the inferior frontal gyrus and the precentral gyrus when choosing the probabilistic options than HC. Correlations were also calculated between behavioral performances and brain activities in relevant brain regions. Both of the behavioral performance and fMRI results indicate that people with IGD show impaired risk evaluation, which might be the reason why IGD subjects continue playing online games despite the risks of widely known negative consequence.