Brain responses to decision-making in easy and hard choices in internet gaming disorder: Implications for irrepressible gaming behaviours

Impaired decision-making was observed in internet gaming disorder (IGD), however, these studies did not differentiate 'hard' to 'easy' decisions, and only the 'hard' decision-making could reveal the mechanism underlying this issue. We recruited forty-eight individuals with IGD and forty-six recreational internet game users (RGUs) as a control group in this study. fMRI data were collected when they were finishing a value-matching delayed discount task (DDT), which included easy and hard decisions judging based on the indifference points of every participant. The correlations between brain responses during DDT and IGD severity and the effective connectivity between brain regions were calculated. Compared to RGUs, IGD subjects showed enhanced activation in the orbitofrontal cortex (OFC) when facing hard choices, and this feature was associated with IGD severity. In addition, individuals with IGD showed increased effective connectivity from the OFC to the dorsolateral prefrontal cortex and the OFC to the occipital lobe and decreased effective connectivity from the occipital lobe to the OFC. The current study showed that the abnormal activation in the OFC was associated with IGD severity and higher OFC-DLPFC/OFC-occipital lobe effective connectivity and lower occipital lobe-OFC effective connectivity when individuals with IGD faced different choices in the DDT. These findings suggest the neural mechanisms of impulsive decision-making in individuals with IGD due to dysfunction with subjective evaluation and dysfunction of the connection with the executive control system.